405 Pharmaceutical Technology-III

Laboratory

Manual
Course: 410
Subject: Practical-

Molecular Biology & Biotechnology

Prepared By
Md. Imran Nur Manik
M.Pharm
Departmnt of Pharmacy
Uniersity of Rajshahi

Rajshahi-6205, Bangladesh

Available at
Essential Pharma documents
www.pharmacydocs.blogspot.com

INDEX

Sl. No.	Date	Name of the experiment	Page No.
01	15.02.12	Preparation of cold cream.	2 – 5
02	15.02.12	Preparation of vanishing cream.	6 – 8
03	15.02.12	Preparation of shaving cream.	9 – 12

Experiment No. 01	Date: 15.02.12
Name of the experiment: Preparation of cold cream.

Introduction:

Cold cream is a perfect semisolid water in oil (w/o) type emulsion. In cold cream, the main ingredient is oil. It is also referred to as beeswax-borax emulsion.

In cold cream, 1-4% water is dispersed at 96-99% of oil. When it is applied to skin, cream is readily absorb and produces a feeling of coolness.

In winter season, water evaporates from the skin. So, skin becomes dry and rough. Cold cream gives an oily protective covering over the skin and consequently water cannot evaporate out.

Formula of cold cream:

Ingredients	Theoretical content	Weighed content
Beeswax	24.5 gm
Liquid paraffin	56 ml
Borax	0.5 gm
Glycerin	4.28 ml
Distilled water	14 ml
Methyl paraben	0.2 gm
Propyl paraben	0.02 gm
Perfume	0.5 ml
Tween-80	0.5 ml

Ideal characteristics of cold cream:

1. The pH of the cold cream must be optimum for maintaining the normal pH of the skin. It should be 4.6–6.
2. Its consistency should be optimum, so that it can be put out easily from the container and apply easily.
3. There should have no oily appearance of cream and should give cooling effect on skin after application.
4. It must provide a waxy protective layer on skin to protect the water evaporation.
5. It should give faster emollient effect, so that very dry skin can swell up and become soft within short time.
6. It should be easily spread on skin.
7. It should be free from gritty particles.
8. It should be nonirritant and nontoxic.
9. It should be attractive in appearance.
10. It should be physically and chemically stable throughout its shelf-life.
11. The additives should be compatible with each other.

Function of ingredients:

1. Beeswax: Beeswax is an important factor in determining quality of the cream. It is the basic raw material of natural origin. It consists of:
1. Approximately 71% esters of wax acid
2. Approximately 10.5–13.5% hydrocarbon
3. Approximately 13.5–14.5% free wax acid
4. 1–1.25% free higher alcohol
5. Cholesterol esters of fatty acid

Purpose of beeswax:

1. It does not develop rancidity.
2. It has no irritant or sensitizing activity.
3. It produces good odour in final product.
4. It generally forms a soft emulsion.

2. Liquid paraffin: It is a hydrocarbon. It is oily in nature and constitutes the oil phase of cold cream.
3. Borax (Na2B4O7 . 10H2O): It is a salt that act as an emulsifying agent. It gives an opaque or white appearance to the preparation and also used for its antiseptic property.
4. Glycerin: It is a hygroscopic substance. It acts as humectants and maintains water content of the preparation. It provides a protective layer on the skin and also helps in smoothing the skin.
5. Perfume: It is essential for cold cream. It should be mildly perfumed so that, it imparts light perfume to the final product. Generally flower fragrances like rose, jasmine, labendar are mainly used.
6. Water: It constitutes the water phase of cold cream. It must be distilled, free from large amount of electrolytes such as Na+, K+, Ca2+ etc.
7. Other additives: These are used to increase the stability, quality and other properties of cold cream. These are given below:
1. Antioxidant: It should be used because of the presence of oil phase. Oil phase is very susceptible to oxidation by atmospheric oxygen, become rancid and produce bad odour to the preparation. Some examples of antioxidant are BHT, BHA, ascorbic acid, tocopherol etc. The usual range is 0.01–0.03%.
2. Preservative: It is used to prevent the bacterial contamination to the water phase as well as the oily phase. It must be dissolved in both water and oil phase. Some examples of preservative are methyl paraben, propyl paraben etc.
3. Colour: Generally no colour is used, because borax provides a very nice white colour. The white colour is sufficient to make the preparation very attractive. If any required, FDA colour should be used.

Apparatus:

1. Beaker 5.   Thermometer
2. Balance 6.   Measuring cylinder
3. Water bath 7.   Container
4. Glass rod 8.   Heater

Procedure:

The following steps are involved in the preparation of cold cream:

1. Preparation of oil phase
2. Preparation of water phase
3. Addition of water phase to oil phase
4. Milling of cream
5. Filling, labeling and packaging of cream

1. Preparation of oil phase: At first all the required ingredients were dispensed for the preparation. Beeswax and liquid paraffin were melted in a beaker at 70°C and the oil phase was prepared. Proper care was taken so that, temperature did not exceed 70°C.
2. Preparation of water phase: Borax and glycerin were dissolved in water in another beaker and the temperature was brought to 70°C. The prepared solution was water phase.
3. Addition of water phase to oil phase: The water phase was then added to the oil phase with continuous one direction stirring.
4. Milling of cream: All other ingredients were added at 70°C except perfume and stirring was continued. When the temperature reduced to 45°C then perfume was added. The methyl paraben should be dissolved in small amount of water before adding it.
5. Filling, labeling and packaging: Finally it was checked analytically. When the temperature of the cold cream reduced to 40°C, then it was filled in a suitable jar. The jar was properly labeled and packaged in a suitable container or paper package.

Mechanism of emulsion formulation:

Borax is added as an emulsifying agent. The basic reaction involves in the manufacturing of beeswax-borax cleansing cream is the hydrolysis of borax and subsequently reaction with free acids present in beeswax to form the corresponding salt or soap. This soap emulsified the liquid paraffin in water. Other components of beeswax are myricyl alcohol, myricyl palmitate etc.

Uses of cold cream:

1. Cold cream is used for skin care. Skin gradually losses water and oil content. As a result it becomes rough and fails to retain normal features. To avoid these conditions, cold cream is applied to the skin.
2. Cold cream gives an oily protective layer in the skin.
3. The oil content of cream gives polishing effect on the skin.
4. It removes oil soluble impurities.

Labeling:

Homa Cold cream (Moisture control 100 gm) MRP: Batch No.: Mfg date: Exp date: Manufactured by: Pharmaceutical Lab. of RU.

Ingredients: Beeswax, Borax, Liquid paraffin, Glycerin, Water, Methyl and Propyl paraben, Perfume and Tween-80. Precaution: Store in cool and dry place. For external use only. Direction to use: Use twice daily on cleaned face for best results.

Market preparation:

1. Lakme 4.   Pond’s
2. Garnier 5.   Johnson & Johnson’s baby cream
3. Meril 6.   Cute

Experiment No. 02	Date: 15.02.12
Name of the experiment: Preparation of vanishing cream.

Introduction:

Vanishing cream is a perfect semisolid oil water (o/w) emulsion. It must be vanished after use. Appearance is fairly light. It is well polished preparation with pearl like appearance. It is softer than cold cream.

Ideal characteristics of vanishing cream:

1. It should be easily spread on the skin.
2. It should be vanished after application.
3. It should be physically and chemically stable.
4. Ingredients used must be compatible with each other.
5. It should not too alkaline and pH (about 6) should be maintained properly.
6. It should not be too much greasy or oily.
7. It should not be too viscous.
8. It should be nontoxic and nonirritant.
9. It should not be too much dry before application.
10. It should be easy to wash out after application.

Formula of a vanishing cream:

Ingredients	Theoretical content	Weighed content
Stearic acid	25 gm
NaOH	0.5 gm
Glycerin	3 ml
Methyl paraben	0.25 gm
Propyl paraben	0.002 gm
Perfume	0.5 ml
Distilled water	70 ml

Function of ingredients:

1. Stearic acid: It is used to constitute the oil phase of vanishing cream. It is very popular, because it provides sparkling appearance to the cream.
2. NaOH: NaOH forms the salt Na-stearate with stearic acid which acts as both emulsifier and opacifier. It partially dissolved in water, which makes the product more stable. All NaOH must be neutralized by reacting with stearic acid, otherwise excess NaOH will cause skin irritation. Instead of NaOH, KOH can be used.
3. Glycerin: It acts as humectants i.e. it hold water in the skin and also in the preparation. In the formulation, it also helps to dissolve NaOH in solution.
4. Preservatives: As the vanishing cream is an o/w type emulsion, it is very much susceptible to the microbial contamination. To prevent this, preservatives are used. Some examples are methyl paraben, propyl paraben etc.
5. Water: It constitutes the water phase of the vanishing cream. It must be distilled, free from large amount of electrolytes such as Na+, K+, Ca2+ etc.
6. Other additives: These are used to increase the stability, quality, attractiveness and other properties of vanishing cream. These are given below:
1. Antioxidant: Though vanishing cream contains small amount of oil, but there is a chance of oxidation of oil which may cause degradation of the formulation. To prevent this oxidation, antioxidants are used. Some examples of antioxidant are BHT, BHA, ascorbic acid, tocopherol etc. The usual range is 0.01–0.03%.
2. Colour: Generally no colour is used in the preparation of vanishing cream. If any required, FDA colour should be used.
3. Perfume: It is must for vanishing cream. Generally aromatic water and perfumery oil are used to get strong fragrance.

Apparatus:

1. Beaker 5.   Thermometer
2. Balance 6.   Measuring cylinder
3. Water bath 7.   Container

4. Glass rod 8.   Heater

Procedure:

The steps which were followed during the preparation of vanishing cream are given below:

1. At first, all the ingredients required for the preparation were dispensed properly.
2. Stearic acid was melted at 60–70°C in a beaker, which constituted the oil phase of the cream.
3. NaOH was dissolved in glycerin and water in another vessel and the temperature of that solution was brought to 65°C. This solution constituted the water phase.
4. Then oil phase was dispersed in water phase by continuous one-direction stirring and maintained the same temperature.
5. At the same time, all other excipients (except perfume) were added with continuous stirring. Finally perfume was added to the formulation at 40-42°C.
6. When the temperature of the preparation reached to 30°C, then it was filled in a suitable jar and labeled.

Mechanism of emulsion formulation:

The basic reaction involves in the manufacturing of vanishing cream is the reaction of the stearic acid with NaOH to form the corresponding salt or soaps Na-stearate. These soaps emulsify the water in stearic acid. Na-stearate acts both as an oil phase and emulsifier.

Uses of vanishing cream:

1. It supplies water to the skin, so it remains smooth and soft.
2. The oil content of the cream gives a polishing effect to the skin.
3. It removes some extent water soluble impurities.
4. It is used for skin care.
5. It gives an emollient action on the skin.

Labeling:

Homa Vanishing cream (Oil control system 100 gm) MRP: Batch No.: Mfg date: Exp date: Manufactured by: Pharmaceutical Lab. of RU.

Ingredients: Stearic acid, NaOH, Glycerin, Methyl and Propyl paraben, Perfume and water. Precaution: Store in cool and dry place. For external use only. Direction to use: Use twice daily on cleaned face for best results.

Market preparation:

1. Lakme 4.   Pond’s
2. Garnier 5.   Fair & Lovely
3. Meril 6.   Cute

Experiment No. 03	Date: 15.02.12
Name of the experiment: Preparation of lather shaving cream.

Introduction:

Lather shaving cream is a cream which is used for smooth, easy and comfortable shave and to keep the skin rich and refresh afterwards. Shaving with a razor without assistance of cosmetic preparation is possible but certainly less convenient. In less favourable circumstance, shaving cream can lead to discomfort irritation and actual physical damage of the skin. These hazards can be minimized by the intelligence choice of shaving cream and shaving instruments.

Ideal characteristics of lather shaving cream:

1. A small quantity must give sufficient lather.
2. It must produce stable foam on shaving.
3. It causes hair swelling and softening.
4. It must be free from skin irritation.
5. Must have no smarting or astringent effect on the skin.
6. Must remain soft in the tube and not go lumpy if overheated.
7. Its stability should be adequate at various temperatures with geographically different areas.
8. It should be noncorrosive to razor blade and not cause dulling of razor blade.
9. Must be sufficiently tacky to adhere to both brush and face yet be easily washed of the razor.

Formula of lather shaving cream:

Ingredients	Theoretical content	Weighed content
Stearic acid	35 gm
Coconut oil	10 ml
Glycerin	10 ml
Borax	0.6 gm
NaOH	2 gm
Perfume	0.5 ml
Water	36 ml
KOH	6.1 gm
Methyl paraben	0.18 gm
Propyl paraben	0.02 gm

Function of each ingredients:

1. Stearic acid: In shaving cream, stearic acid acts as super fatting agent. It is used for the following purposes:
1. To make the lather soften.
2. To increase the stability of foam.
3. As a lubricating agent on skin.
4. To neutralize any free alkali that might be present in the preparation.
5. To act as oil phase.
2. Coconut oil: In shaving cream, coconut oil serves as super fatting agent. It helps:
1. To make the cream softer.
2. To increase the stability of the foam.
3. It has lubricating effect on the skin.
3. Glycerin: It acts as humectants which often help to retain water in the formulation and thus help to keep normal form i.e. the cream soft. Other functions are:
1. Improves wetting property of cream
2. Prevent too rapid drying of  lather
3. Make the skin more elastic
4. Soften the beard
5. Facilitate the transit of the razor over the face
4. Borax (Na2B4O7 . 10H2O): In lather shaving cream, minor quantity (0.1–1%) has been used as viscosity imparting agent.
5. NaOH: NaOH forms the salt Na-stearate with stearic acid. Na-stearate acts both as oil phase and emulsifier.
6. Water: It is used as water phase.
7. Preservatives: Shaving cream is slightly alkaline. This alkalinity favours the growth of microorganism. Due to stability consideration and economical view points, shaving creams are not sterilized. So, preservatives are included to inhibit the microbial growth.
8. Perfumes: These are used to mask the unpleasant odour of the surfectants and super fatting agent and to offer a pleasant sensation.
9. Viscosity imparting agent: It is essential for shaving cream to keep them correctly consistent which must remain stable over a wide range of temperature.
10. Colour: It is not essential in shaving cream.
11. Antiseptic: Minor cuts may occur during shaving. To set remedy from every hazard, antiseptic is added to the formulation.
12. Astringent: During shaving, bleeding may occur due to any cuts. So, astringents (e.g. alum) are used which constricts the exposed capillary and help to stop bleeding.

Apparatus:

1. Beaker
2. Balance
3. Water bath
4. Glass rod
5. Thermometer
6. Measuring cylinder
7. Container
8. Heater

Procedure:

The following steps are involved in the preparation of vanishing cream:

1. At first, all the ingredients required for the preparation were dispensed properly.
2. Stearic acid and coconut oil were heated together at 75–80°C. This mixture is called as oil phase.
3. Water, glycerin, NaOH and Borax as well as KOH were heated together to the same temperature. It is called as water phase.
4. The water phase was added to the oil phase with slow agitation and continuous one-way gentle stirring. The stirring was continued to 45-47°C and perfume was added. After that, the product was allowed to cool without further stirring.
5. When the temperature of the shaving cream reached to room temperature, then it was filled in a suitable jar and labeled.

Mechanism of emulsion formulation:

The basic reaction involves in the manufacture of the shaving cream is the reaction of stearic acid with NaOH to form the corresponding soaps i.e. Na-stearate. These soaps emulsify the water in the preparation of the lather shaving cream.

Uses of lather shaving cream:

1. It removes the stiffness, roughness of the hair.
2. It causes swelling and softening the hair.
3. It removes oily layer from the hair secreted by sebaceous glands, thus shaving becomes easy and smooth.
4. It helps to hold the hair erect.
5. The foam produced provides a lubricating effect.

Labeling:

Homa Lather shaving cream 100 gm. MRP: Batch No.: Mfg date: Exp date: Manufactured by: Pharmaceutical Lab. of RU.

Ingredients: Stearic acid, Coconut oil, Glycerin, NaOH, KOH, Borax, Water, Methyl and Propyl paraben and Perfume. Precaution: Store in cool and dry place. For external use only. Direction to use: Use on wet and cleaned face for best results.

Market preparation:

1. Gillete 3.   Tibet
2. BiC 4.   Kool

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