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Unformatted text preview: PHCY 6101- Dose Form Lab Fall 2010 LABORATORY 3
POWDERS & GRANULES
Objectives Appreciate the versatility of powders and granules when used per se in therapeutics and in the preparation of other dosage forms. Learn to prepare a bulk powder for the medicinal value of its contents for external application. Learn to prepare agglomerates of powdered materials (granules) to be used for pharmaceutical purpose, such as in making tablets. Powder usually refers to a chemical or mixture of substances in the solid physical state. As a pharmaceutical preparation, powders are intimate mixtures of dry, finely divided drug(s) and/or inactive pharmaceutic ingredients that may be intended for internal (i.e. oral powder) or external use (i.e. topical powder). Bulk powders are usually non-potent and are dosed with measuring devices, such as a teaspoon, the cap of the container, a cup, etc. Dusting powders are fine powders intended to be dusted on the skin through a sifter top container. In general, a single medicinal agent is used as a dusting powder but frequently a base (inert powders) is used to protect the skin from irritation and friction. Powder bases absorb secretions and have a drying effect. Dusting powders should be passed through a fine mesh sieve to ensure that they are grit-free (to avoid mechanical irritation of traumatized areas) and well blended. Most powders for internal use are taken orally after mixing with water, a drinkable liquid, or soft food, and may be intended for local effects (e.g. laxatives) or systemic effects (e.g. analgesics). Other dry powders are packaged for reconstitution with a liquid solvent or vehicle (drug relatively unstable in liquid form), for oral, parenteral (injections) or vaginal administration (douches). Some powders are also intended to be inhaled for local and systemic effects, and are dispensed in metered inhalation aerosols. Granules are prepared agglomerates of smaller particles of powder. They are irregularly shaped but may be prepared to be spherical. They are usually in the 4- to 12-sieve size range, although granules of various mesh sizes may be prepared depending upon their application: granules for constitution or for mixture with beverages or sprinkled on food, granules for encapsulation, effervescent granulated salts, and granulation to be compressed into tablet form. Granules are usually formed by moistening blended powders and passing through a screen or a special granulator. These moist granules are either air or oven
Lab 3: POWDERS & GRANULES 1 PHCY 6101- Dose Form Lab Fall 2010 dried. For drug products with a bitter or salty taste, effervescent granules may be prepared, consisting of mixtures of drug(s) with citric acid and/or tartaric acid and/or sodium biphosphate combined with sodium bicarbonate. Because of their flow properties, granulations are commonly used in tablet making to facilitate the free flow of material from the feeding container (or hopper) into the tablet presses. The three most used methods for the preparations of compressed tablets are: wet granulation method, dry granulation method, and direct compression. Wet granulation is probably the most common method employed for the production of compressed tablets of drugs not degraded by hydrolysis. The steps required in the preparation of tablets by wet granulation method may be separated as follows: (1) weighing and blending the ingredients, (2) preparing the wet granulation, (3) screening the damp mass into pellets or granules, (4) drying, (5) dry screening, (6) lubrication and blending, (7) tableting by compression. In the dry granulation method the granulation is formed not by moistening or adding a binding agent to the powdered drug mixture but by compacting large masses of the mixture ('slugging') and subsequently crushing and sizing these pieces into smaller granules by passing through a screen of desired mesh. Lubricants are added in the usual manner, and tablets are made by compression. For this method, either the active ingredient or the diluent(s) must have cohesive properties in order for the large masses to be formed. Direct compression, as the name implies, consists of compressing tablets directly from powdered material without modifying the physical nature of the material itself. General Lab Instructions: Sieves will be shared by students with neighboring lockers A spatula should be passed under the mesh to recover all granulation prepared. Sieves are NOT to be washed after use. Balance cleaning will be observed (and graded) starting this week. Lab 3: POWDERS & GRANULES 2 PHCY 6101- Dose Form Lab Fall 2010 Laboratory Exercise 1: Prickly Heat Dusting Powder
Erasmus B. Dragon, MD 100 S. Main Street, suite 40 Laramie, WY 82070 Tel. (307) 742-1234 Rx Anthony B. Stuart DEA # ___________ Date: 9/8/2010 4.5 parts 4.5 parts 1 part 2-5 drops
Erasmus B. Dragon M.D. Prickly Heat Dusting powder: Talc Cornstarch Zinc oxide Fragrance (optional) M. Ft. 40 g Sig. Apply to affected area prn Refill – NR 1 2 3 4 prn Method
1. 2. 3. 4. 5. 6. Accurately weigh all ingredients required to prepare 40 g of medicinal powder. Add cornstarch, talc and zinc oxide to a zip bag, close zip closure and mix well. Since no pressure is applied to the mixture as it is blended, the resulting powder is light and fluffy. If a fragrance is desired, transfer ~2 mL of ethanol to a small beaker and add 2-5 drops of fragrance. Add this mixture to the zip bag and mix well. If clumps are present, use a household strainer to get rid of clumps before transferring the powder mix to a powder sifter container. Label product. Alternatively, this medicinal powder could be prepared as follows. a) Blend cornstarch and talc by spatulation on top of a piece of wax paper or ointment tile. b) Add cornstarch-talc mixture to zinc oxide using geometric dilution. c) Since pressure will be applied to the mixture as powders are blended, the resulting powder will require sifting to produce a light and fluffy product for dusting the skin. Note: No trituration (in mortar) is required to reduce particle size because all ingredients are very fine powders. Trituration would also require final sieving in order to remove clumps. Lab 3: POWDERS & GRANULES 3 PHCY 6101- Dose Form Lab Fall 2010 Labels
Dewy Cheatham & Howe Pharmacy 9876 W. Broadway Greenplace, ZZ 12345 Tel. (777) 234-5678 Rx 1-MGT-Q12 Anthony B. Stuart Prickly Heat Dusting powder, 40 g Apply to affected area of the skin for stinging and itching caused by prickly heat. Exp. 1 year (use actual date) Refills: 01 MGT (Preparer’s initials) Date: 9/8/2010 Dr. Erasmus B. Dragon, MD For external use only Do not apply near nose or eyes Store in a dry place Keep out of reach of children Lab 3: POWDERS & GRANULES 4 PHCY 6101- Dose Form Lab Fall 2010 Laboratory Exercise 2: Granules (for tablet preparation)
Granulation for the preparation of Acetaminophen 500 mg Compressed Tablets: (Wet Granulation Method) Each tablet contains: Acetaminophen Polyvinylpyrrolidone (K-15) Lactose Alcohol *Stearic Acid *Talc Starch 500 mg 35 mg 85 mg enough to dampen the powder mixture 13.3 mg 20 mg 35 mg + 35 mg* Make granulation enough to prepare 20 tablets. * These ingredients will not be used; do not weigh them! Method: 1. Blend acetaminophen, lactose and half of the starch on ointment slab using spatulation. Reserve. 2. Use ceramic casserole to disperse polyvinylpyrrolidone in alcohol using a plastic spatula to mix. 3. Add mixture prepared in ceramic casserole to powder mixture on ointment slab and combine well. Include an additional 2-3 ml (not to exceed 4 ml) of alcohol to dampen the powder mass appropriately. 4. Make granules by pressing the damp mass through a No. 8-mesh screen and collecting into a piece of wax paper. Do NOT rinse the sieve! 5. Transfer the powder to a piece of aluminum foil folded as a weighing dish and dry the granules in a drying oven for ~10-15 min at 150 °C (oven setting = 6). 6. Hand out the product in a 1 oz. container. Label the product with “Granulation for Acetaminophen 500 mg compressed Tablets”, your name, date, and desk number. When preparing tablets: 7. After drying, the granules are passed through a No. 18-mesh screen. 8. Talc, stearic acid and the other portion of starch are added to the granulation and the mixture is fed into the hopper of the tablet machine for tableting. Lab 3: POWDERS & GRANULES 5 ...
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This note was uploaded on 10/15/2010 for the course PHCY 6101 taught by Professor Teixeira during the Fall '10 term at Pima CC.
- Fall '10