It is also referred to as atomizer. A device such as mask or mouthpiece that turns the liquid into condensed water vapor or fine mist for inhalation into the lungs.
It is often given in the delivery of asthma medications.
Showing posts with label Pharmaceutics. Show all posts
Showing posts with label Pharmaceutics. Show all posts
Wednesday, March 23, 2011
Mouthwash
A medicated solution used for rinsing and gargling the mouth resulting in increased oral hygiene.
Lozenge
It is a type of candy or small pellet which is medicated or aromatic. It is intended for slow dissolution in the mouth and often a demulcent is used in lozenges i.e. a substance helpful in soothing the mucus membrane which is inflamed.
Wednesday, March 9, 2011
Efflorescence
It is the loss of water from a crystal.
It means “to flower out” in French.
It is the spontaneous loss of water (or solvent) from a hydrated or solvated salt to the atmosphere on exposure to air, which occurs when the aquous tension of the hydrate is greater than the partial pressure of the water vapor in the air.
Efflorescent:
Denoting a crystalline body that gradually changes to a powder by losing its water of crystallization on exposure to a dry atmosphere.
Explanation:
If the vapor pressure of a hydrated salt is greater than the pressure exerted by the water vapor in the surrounding atmosphere than the salt will attempt to attain equilibrium with its surroundings and therefore tend to lose water to form a lower hydrate or an anhydrous salt.
This phenomenon is known as efflorescence.
The pressure of water vapor in the atmosphere is about 13.33 x 10^2 N/m^2 at 293 K.
Therefore hydrates with vapor pressure greater than this will tend to exhibit efflorescence and be unstable provided that the lower hydrate that if formed still exerts a vapor pressure greater than the surrounding atmosphere.
If this is not so then water will be taken up from the atmosphere by the lower hydrate as fast as it is formed and the final equilibrium will depend on the rates at which water is lost or taken up the two hydrates.
Examples:
The behavior of the various forms of sodium carbonate may be represented by the following scheme:
Na2CO3.10H2O (v.p = 32 x 10^2 N/m^2 at 293K) --> (Spontaneous dehydration i.e. efflorescence) Na2CO3.H2O (v.p. = 16 x 10^2 N/m^2 at 293K)--> (efflorescence not observable because anhydrous salt is rapidly hydrated) --> Na2CO3 (anhydrous) (v.p. = 0)
Since the vapor pressure exerted by the decahydrate is much greater than that of normal atmosphere. It loses water by the process of efflorescence and is converted to the monohydrate.
The vapor pressure of the later is still above that of the atmosphere but further apparent loss of water does not occur. Since the anhydrous salt is rehydrated at a faster rate than dehydration of the monohydrate.
Similarly, vapor pressure of Glauber’s salt (Na2SO4.10H2O) normally exceed that of the water vapor in the atmosphere these salts effloresce and their surface assumes a powdry appearance. Blue stone or blue vitriol (CuSO4.5H2O)is a blue crystalline solid that when exposed to air slowly loses water of crystallization from its surface to form a white layer of anhydrous copper (II) sulfate.
Factors affecting efflorescence:
The vapor pressure of hydrated salts, and therefore the rate of efflorescence increases with rise in temperature.
Pressure of vapors.
Reduction of efflorescence:
Since the instability that arises from efflorescence is caused by the loss of water vapor. The common method of minimizing such deterioration involves the use of containers that present the loss of water vapor.
The additional precautions of using well filled containers with a minimum amount of atmosphere above the efflorescent material and storage in a cool place are also advisable.
It means “to flower out” in French.
It is the spontaneous loss of water (or solvent) from a hydrated or solvated salt to the atmosphere on exposure to air, which occurs when the aquous tension of the hydrate is greater than the partial pressure of the water vapor in the air.
Efflorescent:
Denoting a crystalline body that gradually changes to a powder by losing its water of crystallization on exposure to a dry atmosphere.
Explanation:
If the vapor pressure of a hydrated salt is greater than the pressure exerted by the water vapor in the surrounding atmosphere than the salt will attempt to attain equilibrium with its surroundings and therefore tend to lose water to form a lower hydrate or an anhydrous salt.
This phenomenon is known as efflorescence.
The pressure of water vapor in the atmosphere is about 13.33 x 10^2 N/m^2 at 293 K.
Therefore hydrates with vapor pressure greater than this will tend to exhibit efflorescence and be unstable provided that the lower hydrate that if formed still exerts a vapor pressure greater than the surrounding atmosphere.
If this is not so then water will be taken up from the atmosphere by the lower hydrate as fast as it is formed and the final equilibrium will depend on the rates at which water is lost or taken up the two hydrates.
Examples:
The behavior of the various forms of sodium carbonate may be represented by the following scheme:
Na2CO3.10H2O (v.p = 32 x 10^2 N/m^2 at 293K) --> (Spontaneous dehydration i.e. efflorescence) Na2CO3.H2O (v.p. = 16 x 10^2 N/m^2 at 293K)--> (efflorescence not observable because anhydrous salt is rapidly hydrated) --> Na2CO3 (anhydrous) (v.p. = 0)
Since the vapor pressure exerted by the decahydrate is much greater than that of normal atmosphere. It loses water by the process of efflorescence and is converted to the monohydrate.
The vapor pressure of the later is still above that of the atmosphere but further apparent loss of water does not occur. Since the anhydrous salt is rehydrated at a faster rate than dehydration of the monohydrate.
Similarly, vapor pressure of Glauber’s salt (Na2SO4.10H2O) normally exceed that of the water vapor in the atmosphere these salts effloresce and their surface assumes a powdry appearance. Blue stone or blue vitriol (CuSO4.5H2O)is a blue crystalline solid that when exposed to air slowly loses water of crystallization from its surface to form a white layer of anhydrous copper (II) sulfate.
Factors affecting efflorescence:
The vapor pressure of hydrated salts, and therefore the rate of efflorescence increases with rise in temperature.
Pressure of vapors.
Reduction of efflorescence:
Since the instability that arises from efflorescence is caused by the loss of water vapor. The common method of minimizing such deterioration involves the use of containers that present the loss of water vapor.
The additional precautions of using well filled containers with a minimum amount of atmosphere above the efflorescent material and storage in a cool place are also advisable.
Tuesday, March 8, 2011
Search Methods
Search methods are used in optimization.
In these methods, the response surfaces are examined by different methods in order to determine the combination of independent variables, so that the optimum results can be obtained. Response surface methodology is used to determine the connection between different explanatory variables (independent variables) and one or more of the response variables (dependent variables).
Following steps are followed in the search methods:
1. A system is selected
2. Independent and Dependent variables are selected
3. Experiments are performed and product is tested
4. Data is submitted (to computer) for statistical and regression analysis
5. Specifications are set for feasibility program
6. Constraints are set for grid search
7. Grid search printouts are evaluated
8. Partial derivative plots (single or composite) and contour plots are evaluated.
In these methods, the response surfaces are examined by different methods in order to determine the combination of independent variables, so that the optimum results can be obtained. Response surface methodology is used to determine the connection between different explanatory variables (independent variables) and one or more of the response variables (dependent variables).
Following steps are followed in the search methods:
1. A system is selected
2. Independent and Dependent variables are selected
3. Experiments are performed and product is tested
4. Data is submitted (to computer) for statistical and regression analysis
5. Specifications are set for feasibility program
6. Constraints are set for grid search
7. Grid search printouts are evaluated
8. Partial derivative plots (single or composite) and contour plots are evaluated.
Saturday, March 5, 2011
Transferosome
Transferosome is a proprietary drug delivery technology of the German company IDEA AG.
Transferosome means "Carrying body". It is a type of artifical vesicle and is considered to be suitable for carrying drug to required target.
Transferosome means "Carrying body". It is a type of artifical vesicle and is considered to be suitable for carrying drug to required target.
Saturday, February 26, 2011
Liposome
Introduction:
Liposome is the type of extremely small artificial sacks made up of lipid monolayers or the layers can be more than one.
The outer layers are very reactive chemically and helps in the coupling of antigens, nucleic acid probes, cell recpetors and antibodies.
Size:
Liposomes may range from 50 nm to 800 nm.
Liposome is the type of extremely small artificial sacks made up of lipid monolayers or the layers can be more than one.
The outer layers are very reactive chemically and helps in the coupling of antigens, nucleic acid probes, cell recpetors and antibodies.
Size:
Liposomes may range from 50 nm to 800 nm.
Lyophilization
It is also referred to as “freeze-drying”, “sublimation-drying” or “cryodesiccation”.
Definition:
It is the process of isolation of a substance (solid) from solution by freezing it and evaporating the ice under vacuum (by sublimation).
Process of lyophilization:
In the process of lyophilization, water or any other solvent is removed from a frozen solution by sublimation caused by reduction of the temperature and pressure to values at a lower level than the triple point.
Under the application of these conditions, heat applied is used as latent heat and the ice converts directly to the vapor state (by the process of sublimation).
Practically, the following features must be taken into account.
Temperature and pressure are necessary to be at a lower level than the triple point and it is usually -10 ºC to -30 ºC and 10 N/m2 to 30 N/m2 respectively. To achieve this pressure, the vapors must be removed or else the vapor pressure will affect this pressure.
Stages of the freeze-drying process:
Following stages are found in lyophilization:
1. Freezing
2. Vacuum
3. Primary drying
4. Secondary drying
5. Packaging
Freezing:
The material is usually frozen before the application of vacuum. A number of methods are used in freezing of the material.
In shell freezing, the bottle is partially filled with the material to be frozen. It is placed in a refrigerator almost horizontally and rotated slowly. In this way the material freezes along side the walls of the bottle and resulting in large area for heat transfer and sublimation.
In vertical spin freezing, small crystals of ice are produced. In this method, the bottles are first placed in a moderate coldness and rotated quickly in vertical position in a constant flow of very cold air. This result in the liquid becoming super cooled and freezing occurs rapidly.
Vacuum:
Vacuum pumps are used to create the vacuum and reducing the pressure sufficiently.
On small scale, two-stage rotary pumps are used while on large scale ejector pumps are used.
Primary drying:
During the primary drying, two important processes are followed i.e. (1) vapors are removed by applying (2) the latent heat of sublimation. The apparatus similar to the vacuum oven can be used.
Heat transfer is crucial in this process as the extra heat may cause the material to melt and less heat may cause the process to be prolonged or no sublimation. So, heat transfer must be controlled.
Vapor removal is important to reduce a change in pressure. On the small scale, vapor is removed by using desiccant such as phosphorus pentoxide or by using a small condenser. And on the large scale condensation is helpful to remove vapors and by using pumps such ejector pumps.
The rate of drying in lyophilization is very low showing that the rate of drying of ice is about 1 mm depth per hour.
Secondary drying:
The primary drying may leave about 0-5 % of moisture in the solid, which can be removed by secondary drying process.
In this method, temperature may raise above 0 ºC to break any type of physico-chemical interactions between the frozen material and the water molecules resulting in the removal of the moisture.
High temperature can be used, as the risk of hydrolysis is negligible in the secondary drying because the secondary drying is an ordinary vacuum drying phase.
Packaging:
After the completion of freeze-drying process, vacuum is usually removed by the application of an inert gas such as nitrogen before the material is tightly closed. Great care is needed in the packaging of freeze dried products. Containers must be tightly closed to protect from moisture.
Freeze-drying equipment:
There are three types of freeze-dryers:
1. Rotary evaporators
2. Manifold freeze-dryers
3. Tray freeze-dryers
Uses:
Aqueous solutions and/or dispersions of oxygen-sensitive or heat-sensitive drugs, biologicals such as blood products (such as peptides, proteins), antibiotics (other than penicillin), vaccines (such as BCG, yellow fever, smallpox) and enzyme preparations (such as hyaluronidase) and microbiological cultures are usually freeze-dried.
After freeze-drying and packing the material in a vial, the material can be stored, shipped and reconstituted later to the primary form for the use as injection.
It increases the shelf life of some of the pharmaceuticals for many years.
Advantages of lyophilization:
1. Decomposition and hydrolysis of the product is reduced as a result of prevention of the enzyme action due to very low temperature.
2. Oxidation is reduced as a result of high vacuum and less air.
3. The product is light and porous as the original solution was frozen and there is no incorporation of extra materials.
4. As the product is porous so this results in more solubility.
Disadvantages of lyophilization:
1. The high porous nature (results in more solubility) and highly dried state results in a highly hygroscopic product. So special conditions are required up to packaging.
2. The process is very slow and requires expensive instruments and plants.
Definition:
It is the process of isolation of a substance (solid) from solution by freezing it and evaporating the ice under vacuum (by sublimation).
Process of lyophilization:
In the process of lyophilization, water or any other solvent is removed from a frozen solution by sublimation caused by reduction of the temperature and pressure to values at a lower level than the triple point.
Under the application of these conditions, heat applied is used as latent heat and the ice converts directly to the vapor state (by the process of sublimation).
Practically, the following features must be taken into account.
Temperature and pressure are necessary to be at a lower level than the triple point and it is usually -10 ºC to -30 ºC and 10 N/m2 to 30 N/m2 respectively. To achieve this pressure, the vapors must be removed or else the vapor pressure will affect this pressure.
Stages of the freeze-drying process:
Following stages are found in lyophilization:
1. Freezing
2. Vacuum
3. Primary drying
4. Secondary drying
5. Packaging
Freezing:
The material is usually frozen before the application of vacuum. A number of methods are used in freezing of the material.
In shell freezing, the bottle is partially filled with the material to be frozen. It is placed in a refrigerator almost horizontally and rotated slowly. In this way the material freezes along side the walls of the bottle and resulting in large area for heat transfer and sublimation.
In vertical spin freezing, small crystals of ice are produced. In this method, the bottles are first placed in a moderate coldness and rotated quickly in vertical position in a constant flow of very cold air. This result in the liquid becoming super cooled and freezing occurs rapidly.
Vacuum:
Vacuum pumps are used to create the vacuum and reducing the pressure sufficiently.
On small scale, two-stage rotary pumps are used while on large scale ejector pumps are used.
Primary drying:
During the primary drying, two important processes are followed i.e. (1) vapors are removed by applying (2) the latent heat of sublimation. The apparatus similar to the vacuum oven can be used.
Heat transfer is crucial in this process as the extra heat may cause the material to melt and less heat may cause the process to be prolonged or no sublimation. So, heat transfer must be controlled.
Vapor removal is important to reduce a change in pressure. On the small scale, vapor is removed by using desiccant such as phosphorus pentoxide or by using a small condenser. And on the large scale condensation is helpful to remove vapors and by using pumps such ejector pumps.
The rate of drying in lyophilization is very low showing that the rate of drying of ice is about 1 mm depth per hour.
Secondary drying:
The primary drying may leave about 0-5 % of moisture in the solid, which can be removed by secondary drying process.
In this method, temperature may raise above 0 ºC to break any type of physico-chemical interactions between the frozen material and the water molecules resulting in the removal of the moisture.
High temperature can be used, as the risk of hydrolysis is negligible in the secondary drying because the secondary drying is an ordinary vacuum drying phase.
Packaging:
After the completion of freeze-drying process, vacuum is usually removed by the application of an inert gas such as nitrogen before the material is tightly closed. Great care is needed in the packaging of freeze dried products. Containers must be tightly closed to protect from moisture.
Freeze-drying equipment:
There are three types of freeze-dryers:
1. Rotary evaporators
2. Manifold freeze-dryers
3. Tray freeze-dryers
Uses:
Aqueous solutions and/or dispersions of oxygen-sensitive or heat-sensitive drugs, biologicals such as blood products (such as peptides, proteins), antibiotics (other than penicillin), vaccines (such as BCG, yellow fever, smallpox) and enzyme preparations (such as hyaluronidase) and microbiological cultures are usually freeze-dried.
After freeze-drying and packing the material in a vial, the material can be stored, shipped and reconstituted later to the primary form for the use as injection.
It increases the shelf life of some of the pharmaceuticals for many years.
Advantages of lyophilization:
1. Decomposition and hydrolysis of the product is reduced as a result of prevention of the enzyme action due to very low temperature.
2. Oxidation is reduced as a result of high vacuum and less air.
3. The product is light and porous as the original solution was frozen and there is no incorporation of extra materials.
4. As the product is porous so this results in more solubility.
Disadvantages of lyophilization:
1. The high porous nature (results in more solubility) and highly dried state results in a highly hygroscopic product. So special conditions are required up to packaging.
2. The process is very slow and requires expensive instruments and plants.
Statistical Quality Control in Pharmaceutics
Definition:
Statistical quality control (SQC)is defined as:
“The monitoring of quality by application of statistical method in all stages of production.”
Explanation:
Statistical methods of investigation are based on the theory of probability.
• Type of measurement
• Sampling techniques
• Design of Experiments
• Type of Sample distribution
The procedure consists of:
• Proper sampling of product
• Determining quality variations of the sample
• Making inferences to the entire batch under investigation from the observed data
• Once the characteristic data pattern of a process has been determined, the pattern can be utilized to predict the limits within which future data can be expected to fall as a matter of chance, and to determine when significant variations in the process have taken place.
Data Analysis:
Data can be analyzed by using appropriate method of analysis:
t-test:
t-test for comparison of two populations. T-value is calculated and from t-value the P-value is noted from the table:
If
P>0.05; test is non-significant
And if
P<0.05; test is significant.
ANOVA:
It means analysis of variance and is used for comparison of more than 2 parameters.
Objectives:
The objective is to determine whether the major source of observed variations is by chance or assignable.
Types of variations:
Chance variations:
These variations are inevitable because any program of production and inspection has its own unique chance causes of variations which can not be controlled or eliminated and often cannot be identified.
Assignable variations:
These variations can usually be detected and corrected by statistical techniques. Assignable variations are usually caused by machine or a specific batch of production or a container.
Thus the use of SQC permits the:
• Evaluation of magnitude of chance variation of product quality.
• Detection of assignable variations of product quality by means of QC charts.
Statistical quality control (SQC)is defined as:
“The monitoring of quality by application of statistical method in all stages of production.”
Explanation:
Statistical methods of investigation are based on the theory of probability.
It relates to the characteristic of product from both qualitative and quantitative point of views to meet the established standards.
Uses:
It has been used to serve:
• As a basis for improved evaluation of materials through more representative sampling technique
• As a means of achieving sharper control in certain manufacturing processes
• To provide logical approach to variations
Selection:
Selection of appropriate method depends on:• Type of measurement
• Sampling techniques
• Design of Experiments
• Type of Sample distribution
Procedure:
The procedure consists of:
• Proper sampling of product
• Determining quality variations of the sample
• Making inferences to the entire batch under investigation from the observed data
• Once the characteristic data pattern of a process has been determined, the pattern can be utilized to predict the limits within which future data can be expected to fall as a matter of chance, and to determine when significant variations in the process have taken place.
Data Analysis:
Data can be analyzed by using appropriate method of analysis:
t-test:
t-test for comparison of two populations. T-value is calculated and from t-value the P-value is noted from the table:
If
P>0.05; test is non-significant
And if
P<0.05; test is significant.
ANOVA:
It means analysis of variance and is used for comparison of more than 2 parameters.
The objective is to determine whether the major source of observed variations is by chance or assignable.
Types of variations:
Chance variations:
These variations are inevitable because any program of production and inspection has its own unique chance causes of variations which can not be controlled or eliminated and often cannot be identified.
Assignable variations:
These variations can usually be detected and corrected by statistical techniques. Assignable variations are usually caused by machine or a specific batch of production or a container.
Thus the use of SQC permits the:
• Evaluation of magnitude of chance variation of product quality.
• Detection of assignable variations of product quality by means of QC charts.
Sublimation
Definition:
It is conversion of a substance in solid state to a gaseous state, which is not accompanied by the formation of liquid phase.
It is similar in some aspects to the distillation process.
Process of sublimation:
At normal pressures, most of the chemical substances either compounds or elements have three different states of matter at various temperatures. In these circumstances, change from solid state to gaseous state requires a median state that is liquid.
On the other hand, some of the chemical substances such as compounds and elements at certain pressures go directly from solid state to the gaseous state. This occurs when the atmospheric pressure applied on the material is very less to inhibit the molecules from going out of the solid state i.e. a substance go through the process of sublimation only if the vapor pressure is less than that of the triple point for that substance.
Triple point:
The triple point is the point possessing a fixed pressure and temperature at which the solid, liquid and gaseous phases of a material are able to co-exist independently.
If the vapor pressure over the solid substance is more than that of the triple point, the solid will convert to vapor after passage through the liquid phase. The following phase diagram will help to understand the triple point.
Line OA:
In this diagram, line OA shows the melting points of the solid substance at different pressures. In this line, left side shows the existence of solid form while the right side shows the existence of liquid form. This line shows the points of co-existence of the solid and the liquid.
Line OB:
The line OB shows the vapor-pressure curve of the liquid at different temperatures. Above this line liquid phase exists and below this line vapor phase of the substance exists. This line shows the points of co-existence of the liquid and the vapors.
Line OC:
The line OC shows the sublimation curve of the solid. This line shows the points of co-existence of the solid and the vapors at different states of temperatures and pressure.
Point O:
In this diagram, the point O represents the triple point.
Enthalpy:
Enthalpy of sublimation is equal to the sum of enthalpy of fusion and enthalpy of vaporization.
Sublimation process represents an endothermic phase transition as shown by the phase diagram.
Examples:
Nearly all of the solids have some tendency of conversion from solid to gaseous state at a particular temperature and pressure.
Elements:
Cadmium, Zinc, Arsenic, Carbon
Compounds:
CO2 (Dry ice), NH4Cl
Uses:
Its most important use is in freeze-drying.
It is conversion of a substance in solid state to a gaseous state, which is not accompanied by the formation of liquid phase.
It is similar in some aspects to the distillation process.
Process of sublimation:
At normal pressures, most of the chemical substances either compounds or elements have three different states of matter at various temperatures. In these circumstances, change from solid state to gaseous state requires a median state that is liquid.
On the other hand, some of the chemical substances such as compounds and elements at certain pressures go directly from solid state to the gaseous state. This occurs when the atmospheric pressure applied on the material is very less to inhibit the molecules from going out of the solid state i.e. a substance go through the process of sublimation only if the vapor pressure is less than that of the triple point for that substance.
Triple point:
The triple point is the point possessing a fixed pressure and temperature at which the solid, liquid and gaseous phases of a material are able to co-exist independently.
If the vapor pressure over the solid substance is more than that of the triple point, the solid will convert to vapor after passage through the liquid phase. The following phase diagram will help to understand the triple point.
In this diagram, line OA shows the melting points of the solid substance at different pressures. In this line, left side shows the existence of solid form while the right side shows the existence of liquid form. This line shows the points of co-existence of the solid and the liquid.
Line OB:
The line OB shows the vapor-pressure curve of the liquid at different temperatures. Above this line liquid phase exists and below this line vapor phase of the substance exists. This line shows the points of co-existence of the liquid and the vapors.
Line OC:
The line OC shows the sublimation curve of the solid. This line shows the points of co-existence of the solid and the vapors at different states of temperatures and pressure.
Point O:
In this diagram, the point O represents the triple point.
Enthalpy:
Enthalpy of sublimation is equal to the sum of enthalpy of fusion and enthalpy of vaporization.
Examples:
Nearly all of the solids have some tendency of conversion from solid to gaseous state at a particular temperature and pressure.
Elements:
Cadmium, Zinc, Arsenic, Carbon
Compounds:
CO2 (Dry ice), NH4Cl
Uses:
Its most important use is in freeze-drying.
Friday, February 25, 2011
Elutriation
The word “Elutriation” is derived from the Latin word “elutriare” meaning “to wash out”.
Definition:
It is the separation, purification or removal of something from a mixture by decanting, straining or washing.
Process of elutriation:
In the process of elutriation, the movement of the fluid, generally water or air, is in the opposite direction to that of the sedimentation process.
Types of elutriation:
According to direction:
Vertical elutriation:
In the gravitational process, the larger particles present in water (or any other liquid) will move vertically downwards with the affect of gravity while the small particles in the fluid travels straight up with the fluid. This is a type of vertical elutriation.
Horizontal elutriation:
If a water current of suspended particles is flowed through a settling chamber. The particles that move out of the water current are collected in the bottom of the chamber. This is a type of horizontal elutriation.
Centrifugal elutriation:
In this case the water current is caused to spin with some force resulting in the large centrifugal force on the suspended particles. The heavier particles will settle to the walls of the elutriator or to the bottom.
The DorrClone is an example of a centrifugal-type of classifier.
According to the type of fluid:
• Air elutriation
• Water elutriation
If the velocity of the fluid is smaller than the velocity of setting down of the particles then the particles will settle downwards. On the other hand, if the velocity of the fluid is larger than the velocity of setting down of the particles then the particles will be carried up along with the fluid.
Air elutriation will give precise separation of the particles and in less time than water elutriation.
Factors affecting elutriation:
Elutriation is affected by the
• velocity of the fluid
• the particle size : As the small sized particles will flow (upward) along the fluid while the large sized particles will move downwards (against the velocity of the fluid).
• position of the particle in the (tube containing) fluid
• density of the particle
In a tube, there exist different velocities i.e. the velocity is largest in the centre and is smallest along the walls of the tube. So the small sized particles move upward, when in the centre and in the meantime they are also pushed towards the wall of the tube. Where the velocity is smaller and here the small sized particles start to move downwards.
Process of removal of particles:
If the upward flow of the water (or any other liquid) is slightly increased, the small sized particles (which move down slowly) will move along the movement of the water (i.e. upward) and will be removed from the water. In this process, the medium sized particles will remain immobile and the heavier particles will continue to move downward.
The upward flow of water will then again be increased and the next smallest size particles will be removed. And in this way, particles of different sizes will be separated and obtained.
Definition:
It is the separation, purification or removal of something from a mixture by decanting, straining or washing.
Process of elutriation:
In the process of elutriation, the movement of the fluid, generally water or air, is in the opposite direction to that of the sedimentation process.
Types of elutriation:
According to direction:
Vertical elutriation:
In the gravitational process, the larger particles present in water (or any other liquid) will move vertically downwards with the affect of gravity while the small particles in the fluid travels straight up with the fluid. This is a type of vertical elutriation.
Horizontal elutriation:
If a water current of suspended particles is flowed through a settling chamber. The particles that move out of the water current are collected in the bottom of the chamber. This is a type of horizontal elutriation.
Centrifugal elutriation:
In this case the water current is caused to spin with some force resulting in the large centrifugal force on the suspended particles. The heavier particles will settle to the walls of the elutriator or to the bottom.
The DorrClone is an example of a centrifugal-type of classifier.
According to the type of fluid:
• Air elutriation
• Water elutriation
If the velocity of the fluid is smaller than the velocity of setting down of the particles then the particles will settle downwards. On the other hand, if the velocity of the fluid is larger than the velocity of setting down of the particles then the particles will be carried up along with the fluid.
Air elutriation will give precise separation of the particles and in less time than water elutriation.
Factors affecting elutriation:
Elutriation is affected by the
• velocity of the fluid
• the particle size : As the small sized particles will flow (upward) along the fluid while the large sized particles will move downwards (against the velocity of the fluid).
• position of the particle in the (tube containing) fluid
• density of the particle
In a tube, there exist different velocities i.e. the velocity is largest in the centre and is smallest along the walls of the tube. So the small sized particles move upward, when in the centre and in the meantime they are also pushed towards the wall of the tube. Where the velocity is smaller and here the small sized particles start to move downwards.
Process of removal of particles:
If the upward flow of the water (or any other liquid) is slightly increased, the small sized particles (which move down slowly) will move along the movement of the water (i.e. upward) and will be removed from the water. In this process, the medium sized particles will remain immobile and the heavier particles will continue to move downward.
The upward flow of water will then again be increased and the next smallest size particles will be removed. And in this way, particles of different sizes will be separated and obtained.
Centrifugation
It refers to the process of sedimentation by using centrifuge machine.
Basic idea behind centrifugation:
Centrifugation is based on the widely known idea of sedimentation by the use of centrifugal force, which represents a force that apparently moves a spinning or rotating object away from the axis of rotation in a curved path.
Centrifugal effect:
The processes using centrifugal force (F) can be described by the equations involving the gravitational constant (G). In this case, it is easy to determine the centrifugal force in the terms of the ratio of the centrifugal force to the gravitational force. In addition, this ratio represents the centrifugal effect (C).
Centrifugal effect (C) shows that how many times the centrifugal force is larger than gravitational force.
C = 2.013 dn^2
Where
d = diameter of rotation
n = speed of rotation
Here in this equation, “n” has the value in “s-1” and “d” has the value in “m”.
This equation shows that centrifugal effect is directly proportional to the diameter and to the square of the speed of the rotation i.e. greater will be the diameter of the tube or container more will be centrifugation and similarly for the speed of rotation.
Factors affecting centrifugation:
Centrifugation is basically affected by centrifugal effect. Moreover, nature of the liquid medium in which the particles are placed also affects the centrifugation.
Apparatus for centrifugation (Centrifuges):
Container is the most important part of centrifugation apparatus i.e. centrifuges. This container is used for the placement of a mixture or solution of solid and liquid or of a solution of two liquids.
This container is then rotated at greater speed resulting in the separation of the ingredients of the mixture takes place by the use of centrifugal force.
Mechanism for the separation in the apparatus of centrifugation:
A mixture of liquid or solid in a liquid of low density can be separated as the material of larger density is thrown in the outward direction to the bottom of the tube or container with a larger force. This results in the separation of pure, low-density liquid as a transparent or purified supernatant liquid which forms upper layer.
Types of centrifuges:
There are two basic types of centrifuges:
1. Sedimentation
2. Filtration
Sedimentation centrifuges:
The basic principle, in the sedimentation type of centrifuges, is difference in the densities of the ingredients of the mixture. In these types of centrifuges, the particles are settled to the wall by the action of the centrifugal force.
These types of centrifuges are used for the separation of ingredients of the mixture of solid in liquid as well as liquid in liquid.
Two types of centrifuges are based on the principle of sedimentation:
1. Bottle centrifuge
2. Disc type centrifuge
Bottle centrifuge:
It is mostly used centrifuge machine in the laboratories. It consists of a vertical rotating rod that causes the “bottle-type” containers or test tubes, which are fixed symmetrically, to be rotated in a horizontal plane resulting in the separation of the materials of varying densities. The vertical rod is rotated usually by means of electric motor. Sometimes, gas turbines can also be used for the rotation.
Disk type centrifuge:
It consists of vertical pile of thin conical disks, which are arranged in the manner of one on the top of another. The sedimentation of the particles takes place in the space between neighbouring cones. In this way, settling distance is greatly reduced, thereby increasing the rate at which the particles in the material are separated. The cones are adjusted in such a manner that heavier material moves down the surface easily upon reaching the inner surface of the cone.
It is same in the basic operation to the sedimentation types of centrifuges but instead of solid containers or tubes, it contains a porous wall or perforated containers or baskets, which causes the liquid phase to pass through it but keeps the solid phase on it.
Centrifuge based on the principle of filtration is “Basket centrifuge”.
Basket centrifuge:
Basket centrifuge consists of a porous wall and rotor which is cylindrical and tubular in structure. The porous wall is some times replaced by one or more of the fine mesh screens. The fluid go through the screen where as the particles larger in size are left on the screen.
Centrifugation is used for the separation of ingredients of a mixture of solid in liquid or liquid in liquid as the degree of separation achieved by centrifugation is of greater amplitude than the action due to gravity.
It is important specifically when the separation by normal filtration methods is difficult such as in the separation of fluids of highly viscous nature.
In the pharmaceutical research, it is considered as an important tool in determining the stability of emulsions.
Bottle centrifuge can be used for:
1. Finding the sediments present in crude vegetable and mineral oils
2. Determination of the butterfat content in the milk
3. Various clinical trials and tests
Disk type centrifuge can be used for refining of vegetable oils by removing soap stock
Basket centrifuge can be used for:
1. Drying and washing of several different kinds of crystals and fibrous materials
2. The preparation of cane sugar.
Basic idea behind centrifugation:
Centrifugation is based on the widely known idea of sedimentation by the use of centrifugal force, which represents a force that apparently moves a spinning or rotating object away from the axis of rotation in a curved path.
Centrifugal effect:
The processes using centrifugal force (F) can be described by the equations involving the gravitational constant (G). In this case, it is easy to determine the centrifugal force in the terms of the ratio of the centrifugal force to the gravitational force. In addition, this ratio represents the centrifugal effect (C).
Centrifugal effect (C) shows that how many times the centrifugal force is larger than gravitational force.
C = 2.013 dn^2
Where
d = diameter of rotation
n = speed of rotation
Here in this equation, “n” has the value in “s-1” and “d” has the value in “m”.
This equation shows that centrifugal effect is directly proportional to the diameter and to the square of the speed of the rotation i.e. greater will be the diameter of the tube or container more will be centrifugation and similarly for the speed of rotation.
Factors affecting centrifugation:
Centrifugation is basically affected by centrifugal effect. Moreover, nature of the liquid medium in which the particles are placed also affects the centrifugation.
Apparatus for centrifugation (Centrifuges):
Container is the most important part of centrifugation apparatus i.e. centrifuges. This container is used for the placement of a mixture or solution of solid and liquid or of a solution of two liquids.
This container is then rotated at greater speed resulting in the separation of the ingredients of the mixture takes place by the use of centrifugal force.
Mechanism for the separation in the apparatus of centrifugation:
A mixture of liquid or solid in a liquid of low density can be separated as the material of larger density is thrown in the outward direction to the bottom of the tube or container with a larger force. This results in the separation of pure, low-density liquid as a transparent or purified supernatant liquid which forms upper layer.
Types of centrifuges:
There are two basic types of centrifuges:
1. Sedimentation
2. Filtration
Sedimentation centrifuges:
The basic principle, in the sedimentation type of centrifuges, is difference in the densities of the ingredients of the mixture. In these types of centrifuges, the particles are settled to the wall by the action of the centrifugal force.
These types of centrifuges are used for the separation of ingredients of the mixture of solid in liquid as well as liquid in liquid.
Two types of centrifuges are based on the principle of sedimentation:
1. Bottle centrifuge
2. Disc type centrifuge
Bottle centrifuge:
It is mostly used centrifuge machine in the laboratories. It consists of a vertical rotating rod that causes the “bottle-type” containers or test tubes, which are fixed symmetrically, to be rotated in a horizontal plane resulting in the separation of the materials of varying densities. The vertical rod is rotated usually by means of electric motor. Sometimes, gas turbines can also be used for the rotation.
Disk type centrifuge:
It consists of vertical pile of thin conical disks, which are arranged in the manner of one on the top of another. The sedimentation of the particles takes place in the space between neighbouring cones. In this way, settling distance is greatly reduced, thereby increasing the rate at which the particles in the material are separated. The cones are adjusted in such a manner that heavier material moves down the surface easily upon reaching the inner surface of the cone.
Filtration centrifuges:
These types of centrifuges are used for the separation of the mixture of solid in liquid only performing the operation similar to the filtration process. These are also sometimes referred to as clarifiers.It is same in the basic operation to the sedimentation types of centrifuges but instead of solid containers or tubes, it contains a porous wall or perforated containers or baskets, which causes the liquid phase to pass through it but keeps the solid phase on it.
Centrifuge based on the principle of filtration is “Basket centrifuge”.
Basket centrifuge:
Basket centrifuge consists of a porous wall and rotor which is cylindrical and tubular in structure. The porous wall is some times replaced by one or more of the fine mesh screens. The fluid go through the screen where as the particles larger in size are left on the screen.
Application of centrifugation:
Centrifugation is used for the separation of ingredients of a mixture of solid in liquid or liquid in liquid as the degree of separation achieved by centrifugation is of greater amplitude than the action due to gravity.
It is important specifically when the separation by normal filtration methods is difficult such as in the separation of fluids of highly viscous nature.
In the pharmaceutical research, it is considered as an important tool in determining the stability of emulsions.
Bottle centrifuge can be used for:
1. Finding the sediments present in crude vegetable and mineral oils
2. Determination of the butterfat content in the milk
3. Various clinical trials and tests
Disk type centrifuge can be used for refining of vegetable oils by removing soap stock
Basket centrifuge can be used for:
1. Drying and washing of several different kinds of crystals and fibrous materials
2. The preparation of cane sugar.
Bougies
Introduction:
Its name came from the town namely “bougie” in Algeria, which was famous for trading in wax. Its original meaning is “A candle made by wax”. These are the types of suppositories intended for insertion into the urethra, nostrils or ears.
It is also a medical instrument in the shape of cylinder, made up of a flexible tube.
Forms of bougie:
Bulbous bougie:
It is a form of bougie with a bulb shaped tip.
Eder-pustow bougie:
It is a form of metal bougie which resembles olive in shape. It may be used in esophageal stricture.
Elastic bougie:
A bougie made of rubber or latex.
Elbowed bougie:
A bougie with a bent near its tip.
Use:
It is used for opening of constricted areas in tubular organs such as urethra or esophagus and rectum, so, that medicines for local application or another instruments can easily be inserted in that part.
Its name came from the town namely “bougie” in Algeria, which was famous for trading in wax. Its original meaning is “A candle made by wax”. These are the types of suppositories intended for insertion into the urethra, nostrils or ears.
It is also a medical instrument in the shape of cylinder, made up of a flexible tube.
Forms of bougie:
Bulbous bougie:
It is a form of bougie with a bulb shaped tip.
Eder-pustow bougie:
It is a form of metal bougie which resembles olive in shape. It may be used in esophageal stricture.
Elastic bougie:
A bougie made of rubber or latex.
Elbowed bougie:
A bougie with a bent near its tip.
Use:
It is used for opening of constricted areas in tubular organs such as urethra or esophagus and rectum, so, that medicines for local application or another instruments can easily be inserted in that part.
Thursday, February 24, 2011
Types of properties of solutions
There are following three types of properties of solution:
1. Additive properties
2. Constitutive properties
3. Colligative properties
Additive properties:
These are the properties which are due to sum of corresponding properties of individual atoms or functional groups within the molecules e.g. molecular weight.
Constitutive property:
These are the properties which depend upon the structural arrangement of atoms within the molecules for example optical properties and surface and interfacial properties.
Colligative property:
These are the properties which depend upon the number of molecules present in solution.
Following are colligative properties of dilute solution:
1. Lowering of vapor pressure
2. Elevation of boiling point
3. Depression of freezing point
4. Osmotic pressure
1. Additive properties
2. Constitutive properties
3. Colligative properties
Additive properties:
These are the properties which are due to sum of corresponding properties of individual atoms or functional groups within the molecules e.g. molecular weight.
Constitutive property:
These are the properties which depend upon the structural arrangement of atoms within the molecules for example optical properties and surface and interfacial properties.
Colligative property:
These are the properties which depend upon the number of molecules present in solution.
Following are colligative properties of dilute solution:
1. Lowering of vapor pressure
2. Elevation of boiling point
3. Depression of freezing point
4. Osmotic pressure
Monday, February 21, 2011
Tincture
A tincture is an alcoholic extract (e.g. of leaves or other plant material) or solution of a non-volatile substance (e.g. of iodine, mercurochrome). To qualify as a tincture, the alcoholic extract is to have an ethanol percentage of at least 40-60% (80-120 proof) (sometimes a 90% (180 proof) pure liquid is even achieved). In herbal medicine, alcoholic tinctures are often made with various concentrations of ethanol, 25% being the most common. Other concentrations include 45% and 90%. Herbal tinctures do not always use ethanol as a solvent, though this is the most frequent. Other solvents include vinegar, glycerol, ether and propylene glycol, not all of which are used for internal consumption. However, where a raw solvent's pH factor is a sole consideration, the advantage of ethanol is that being close to neutral pH, it is a good compromise as a passive used solvent of both acidic and alkaline constituents where a tincturing methodology is concerned. Glycerine, when utilized in a tincture methodology's passive (i.e. 'non-critical') manner, is a poorer solvent generally, and vinegar, being acidic, is a better solvent of alkaloids but a poorer solvent of acids, which would result in the alkaloids being more present in the preparation than otherwise. However, for people who do not imbibe alcohol for medical, religious or moral reasons, non-alcoholic (glycerite) tinctures are an alternative.
Alcohol tinctures cannot be subjected to high temperatures and are thus considered a 'non-critical' passive methodology regarding this factor. This is one of the primary reasons why glycerol, due to early Eclectic medicine studies (now for the most part outdated concerning the subject), is typically seen as inferior to alcohol, when utilized in a non-critical tincture methodology fashion (which is how Eclectic medicine researchers utilized glycerol in their tincture making studies), since it does not exhibit the extractive potential of alcohol when used in a low temperature non-critical tincturing setting. Glycerol used in a non-critical tincturing methodology, as is typically done in the herbal products industry at large for instance, will result in a weak solution, whereas if glycerol is subjected to a contemporary innovative serialized methodology currently in the industry, the extractive potential of glycerol is quite astounding. Therefore, glycerite products made using such innovative serialized extraction technologies are showing great promise, even rivaling alcohol tinctures on numerous points.
Solutions of volatile substances were called spirits, although that name was also given to several other materials obtained by distillation, even when they did not include alcohol. In chemistry, a tincture is a solution that has alcohol as the solvent.
General Method of preparation:
A general method of preparation on how tinctures can be prepared is the following:
Advantages of Tincture:
Ethanol is able to dissolve substances which are less soluble in water, while at the same time the water content can dissolve the substances less soluble in ethanol. It is possible to vary the proportion of ethanol and water to produce tinctures with different qualities because of different substances. One example of this is tincture of Calendula officinalis, which is frequently used either at 25% ethanol or 90% ethanol. The solvent also acts as a preservative.
Disadvantages of tinctures
Chemically speaking, ethanol possesses a profound intrinsic denaturing and inert rendering quality. This quality accounts for a large part of ethanol's anti-microbial properties. This denaturing and inert rendering quality also has an undesired effect on many extracted botanical constituents. For instance, alcohol intrinsically fractures and denatures many highly complex aromatic compounds and denatures many extracted for polysaccharides. Other constituents are likewise subjected to denaturing and being rendered inert. The basic tenets of chemistry teach that anytime a biologically viable component is denatured or rendered inert, it will reduce or negate the prior biological viability. This factor needs to be seriously considered and weighed by the clinician or consumer when determining the hoped for biological viability of an ethanol-based botanical tincture both as to sought for efficacy and dosage considerations.
Ether and propylene glycol tinctures are not suitable for internal consumption and are instead used in such preparations as creams or ointments.
Examples of Tinctures:
Some examples that were formerly common in medicine include:
Alcohol tinctures cannot be subjected to high temperatures and are thus considered a 'non-critical' passive methodology regarding this factor. This is one of the primary reasons why glycerol, due to early Eclectic medicine studies (now for the most part outdated concerning the subject), is typically seen as inferior to alcohol, when utilized in a non-critical tincture methodology fashion (which is how Eclectic medicine researchers utilized glycerol in their tincture making studies), since it does not exhibit the extractive potential of alcohol when used in a low temperature non-critical tincturing setting. Glycerol used in a non-critical tincturing methodology, as is typically done in the herbal products industry at large for instance, will result in a weak solution, whereas if glycerol is subjected to a contemporary innovative serialized methodology currently in the industry, the extractive potential of glycerol is quite astounding. Therefore, glycerite products made using such innovative serialized extraction technologies are showing great promise, even rivaling alcohol tinctures on numerous points.
Solutions of volatile substances were called spirits, although that name was also given to several other materials obtained by distillation, even when they did not include alcohol. In chemistry, a tincture is a solution that has alcohol as the solvent.
General Method of preparation:
A general method of preparation on how tinctures can be prepared is the following:
- Herbs are put in a jar and a spirit of 40% pure ethanol is added (80 proof Vodka, for example)
- The jar is left to stand for 2–3 weeks, shaken occasionally, in order to maximise the concentration of the solution.
Advantages of Tincture:
Ethanol is able to dissolve substances which are less soluble in water, while at the same time the water content can dissolve the substances less soluble in ethanol. It is possible to vary the proportion of ethanol and water to produce tinctures with different qualities because of different substances. One example of this is tincture of Calendula officinalis, which is frequently used either at 25% ethanol or 90% ethanol. The solvent also acts as a preservative.
Disadvantages of tinctures
Chemically speaking, ethanol possesses a profound intrinsic denaturing and inert rendering quality. This quality accounts for a large part of ethanol's anti-microbial properties. This denaturing and inert rendering quality also has an undesired effect on many extracted botanical constituents. For instance, alcohol intrinsically fractures and denatures many highly complex aromatic compounds and denatures many extracted for polysaccharides. Other constituents are likewise subjected to denaturing and being rendered inert. The basic tenets of chemistry teach that anytime a biologically viable component is denatured or rendered inert, it will reduce or negate the prior biological viability. This factor needs to be seriously considered and weighed by the clinician or consumer when determining the hoped for biological viability of an ethanol-based botanical tincture both as to sought for efficacy and dosage considerations.
Ether and propylene glycol tinctures are not suitable for internal consumption and are instead used in such preparations as creams or ointments.
Examples of Tinctures:
Some examples that were formerly common in medicine include:
- Tincture of Cannabis sativa
- Tincture of Benzoin
- Tincture of cantharides
- Tincture of ferric citrochloride (a chelate of citric acid and Iron(III) chloride)
- Tincture of green soap (which also contains lavender)
- Tincture of guaiac
- Tincture of iodine
- Tincture of opium (laudanum)
- Camphorated opium tincture (paregoric)
- Tincture of Pennyroyal
- Warburg's Tincture (aka Tinctura Antiperiodica aka Antiperiodic Tincture), an antipyretic medicine of the 19th-century.
- Spirit of ammonia (also called spirit of hartshorn)
- Spirit of box, or ethanol, which was derived from the destructive distillation of boxwood
- Spirit of camphor
- Spirit of ether, a solution of diethyl ether in alcohol
- "Spirit of Mindererus", ammonium acetate in alcohol
- "Spirit of nitre" is not a spirit in this sense, but an old name for nitric acid (but "sweet spirit of nitre" was ethyl nitrite)
- Similarly "spirit(s) of salt" actually meant hydrochloric acid. The concentrated, fuming, 35% acid is still sold under this name in the UK, for use as a drain-cleaning fluid.
- "Spirit of vinegar" was glacial acetic acid and
- "Spirit of vitriol" was sulfuric acid
- "Spirit of wine" or "spirits of wine" is an old name for alcohol (especially food grade alcohol derived from the distillation of wine)
- "Spirit of wood" means methanol, often derived from the destructive distillation of wood
Elixir
An elixir is a clear, sweet-flavored liquid (usually containing alcohol) used in compounding medicines to be taken orally in order to mask an unpleasant taste and intended to cure one's ills.
When used as a pharmaceutical preparation, it contains at least one active ingredient dissolved in a solution that contains 15 to 50% by volume of ethyl alcohol and it is designed to be taken orally.
Types of Elixirs:
1. Non-medicated elixirs:
It is used as a solvent or vehicle for the preparation of medicated elixirs: aromatic elixirs (USP), isoalcholic elixirs (NF) or compound benaldehyde elixirs (NF).
An elixir is a hydro-alcoholic solution of at least one active ingredient. The alcohol is mainly used to:
An elixir may also contain the following excipients:
Elixirs should be stored in a tightly closed and light resistant container away from direct heat and sunlight.
When used as a pharmaceutical preparation, it contains at least one active ingredient dissolved in a solution that contains 15 to 50% by volume of ethyl alcohol and it is designed to be taken orally.
Types of Elixirs:
1. Non-medicated elixirs:
It is used as a solvent or vehicle for the preparation of medicated elixirs: aromatic elixirs (USP), isoalcholic elixirs (NF) or compound benaldehyde elixirs (NF).
2. Medicated elixirs
- Antihistaminic elixirs: used against allergy: chlorampheniramine maleate elixirs (USP), diphenhydramine HCl elixirs.
- Sedative and hypnotic elixirs: sedatives induce drowsiness and hypnotics induce sleep: pediatric chloral hydrate elixirs.
- Expectorant: used to facilitate productive cough (cough with sputum): terpin hydrate elixirs.
- Miscellaneous: acetaminophen (paracetamol) elixirs which are used as analgesic.
An elixir is a hydro-alcoholic solution of at least one active ingredient. The alcohol is mainly used to:
- Solubilize the active ingredient(s) and some excipients
- Retard the crystallization of sugar
- Preserve the finished product
- Provide a certain sharpness to the taste
- Aid in masking the unpleasant taste of the active ingredient(s)
- Enhance the flavor.
An elixir may also contain the following excipients:
- Sugar and/or sugar substitutes like the sugar polyols glycerol and sorbitol.
- Preservatives like parabens and bezoates and antioxidants like butylated hydroxytoluene (BHT) and sodium metabisulfite.
- Buffering agents
- Chelating agents like sodium ethylenediaminetetraacetic acid (EDTA)
- Flavoring agents and flavor enhancers
- Coloring agents
Elixirs should be stored in a tightly closed and light resistant container away from direct heat and sunlight.
Syrup
A syrup is a thick, viscous liquid consisting primarily of a solution of sugar in water, containing a large amount of dissolved sugars but showing little tendency to deposit crystals. The viscosity arises from the multiple hydrogen bonds between the dissolved sugar, which has many hydroxyl (OH) groups, and the water. Syrups can be made by dissolving sugar in water or by reducing naturally sweet juices such as cane juice, sorghum juice, or maple sap. Corn syrup is made from corn starch using an enzymatic process that converts it to sugars. Technically and scientifically, the term syrup is also employed to denote viscous, generally residual, liquids, containing substances other than sugars in solution.
Types of syrups:
1. Non-medicated syrup:
The syrup employed as a base for medicinal purposes consists of a concentrated or saturated solution of refined sugar in distilled water. The "simple syrup" of the British Pharmacopoeia is prepared by adding 1 kg of refined sugar to 500 mL of boiling distilled water, heating until it is dissolved and subsequently adding boiling distilled water until the weight of the whole is 1.5 kg. The specific gravity of the syrup should be 1.33. This is a 66° Brix solution.
2. Medicated syrup
Composition of medicated syrups
Medicated syrups are aqueous solutions containing sugar and at least one water soluble active ingredient.
The sugar is mainly used to:
Syrups may also contain the following excipients:
Preparation of medicated syrups
Syrups are mainly prepared by the following method:
A basic sugar-and-water syrup used to make drinks at bars is referred to by several names, including liquid sugar simple syrup, sugar syrup, simple sugar syrup, gomme, and bar syrup. Simple syrup is made by stirring granulated sugar into hot water in a sauce pan until the sugar is dissolved and then cooling the solution. Generally, the ratio of sugar to water can range anywhere from 1:1 to 2:1.
Simple syrup can be used as a sweetener. However, since it gels readily when pectin is added, its primary culinary use is as a base for fruit sauces, toppings and preserves.
Types of syrups:
1. Non-medicated syrup:
The syrup employed as a base for medicinal purposes consists of a concentrated or saturated solution of refined sugar in distilled water. The "simple syrup" of the British Pharmacopoeia is prepared by adding 1 kg of refined sugar to 500 mL of boiling distilled water, heating until it is dissolved and subsequently adding boiling distilled water until the weight of the whole is 1.5 kg. The specific gravity of the syrup should be 1.33. This is a 66° Brix solution.
2. Medicated syrup
Composition of medicated syrups
Medicated syrups are aqueous solutions containing sugar and at least one water soluble active ingredient.
The sugar is mainly used to:
- Preserve the finished product
- Aid in masking the unpleasant taste of the active ingredient(s)
- Enhance the flavour.
Syrups may also contain the following excipients:
- Sugar polyols like glycerol, maltitol and sorbitol
- Preservatives like parabens and bezoates and antioxidants like butylated hydroxytoluene (BHT) and sodium metabisulfite.
- Acids like citric acid to prevent the recrystallisation of sugar
- Buffering agents
- Chelating agents like sodium ethylenediaminetetraacetic acid (EDTA)
- Flavouring agents and flavour enhancers
- Colouring agents
- Ethyl alcohol (3-4% in volume).
Preparation of medicated syrups
Syrups are mainly prepared by the following method:
- Dissolve ingredients in purified water and because the sugar decreases the solubilizing properties of water, it is added generally at the end.
- Heat and/or agitate actively until the dissolution of all ingredients. If at least one of the ingredients is sensitive to temperature, mixing should take place without heating.
- Strain if needed
- Add sufficient purified water to make the right weight or volume.
A basic sugar-and-water syrup used to make drinks at bars is referred to by several names, including liquid sugar simple syrup, sugar syrup, simple sugar syrup, gomme, and bar syrup. Simple syrup is made by stirring granulated sugar into hot water in a sauce pan until the sugar is dissolved and then cooling the solution. Generally, the ratio of sugar to water can range anywhere from 1:1 to 2:1.
Simple syrup can be used as a sweetener. However, since it gels readily when pectin is added, its primary culinary use is as a base for fruit sauces, toppings and preserves.
Saturday, February 19, 2011
Soft gel
A softgel is an oral dosage form for medicine similar to capsules. They consist of a gelatin based shell surrounding a liquid fill. Softgel shells are a combination of gelatin, water, opacifier and a plasticiser such as glycerin and/or sorbitol(s).
Softgels are produced in a process known as encapsulation using the Rotary Die Encapsulation process invented by Robert Pauli Scherer. The encapsulation process has been described as a form/fill/seal process. Two flat ribbons of shell material are manufactured on the machine and brought together on a twin set of rotating dies. The dies contain recesses in the desired size and shape, which cut out the ribbons into a two dimensional shape, and form a seal around the outside. At the same time a pump delivers a precise dose of fill material through a nozzle incorporated into a filling wedge whose tip sits between the two ribbons in between two die pockets at the point of cut out. The wedge is heated to facilitate the sealing process. The wedge injection causes the two flat ribbons to expand into the die pockets, giving rise to the three dimensional finished product. After encapsulation, the softgels are dried for two days to two weeks depending on the product.
In recent years, manufacturers have been able to replace gelatin in the shell with other polymers based on, for example, starch and carrageenan.
Catalent Pharma Solutions is the current owner of the RPScherer technology .
Softgels are produced in a process known as encapsulation using the Rotary Die Encapsulation process invented by Robert Pauli Scherer. The encapsulation process has been described as a form/fill/seal process. Two flat ribbons of shell material are manufactured on the machine and brought together on a twin set of rotating dies. The dies contain recesses in the desired size and shape, which cut out the ribbons into a two dimensional shape, and form a seal around the outside. At the same time a pump delivers a precise dose of fill material through a nozzle incorporated into a filling wedge whose tip sits between the two ribbons in between two die pockets at the point of cut out. The wedge is heated to facilitate the sealing process. The wedge injection causes the two flat ribbons to expand into the die pockets, giving rise to the three dimensional finished product. After encapsulation, the softgels are dried for two days to two weeks depending on the product.
In recent years, manufacturers have been able to replace gelatin in the shell with other polymers based on, for example, starch and carrageenan.
Catalent Pharma Solutions is the current owner of the RPScherer technology .
Pills
A pill is a small, round, solid pharmacological oral dosage form that was in use before the advent of tablets and capsules. Pills were made by mixing the active ingredients with an excipient such as glucose syrup in a mortar and pestle to form a paste, then rolling the mass into a long cylindrical shape (called a "pipe"), and dividing it into equal portions, which were then rolled into balls, and often coated with sugar to make them more palatable.
In colloquial usage, tablets, capsules, and caplets are still often referred to as "pills" collectively.
In colloquial usage, tablets, capsules, and caplets are still often referred to as "pills" collectively.
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