Chapter 3 Powders and granules.pptVIP

Chapter 3 Powders and granules 2007.1.14 Definition of powders Connotation(涵义) 1, the physical form of a material a dry substance composed of finely divided particles The use of powdered substances in the preparation of other dosage forms is extensive. For example, a. tablets and capsules; b. liquid dosage forms (solutions or suspensions); c. ointments and creams. Connotation 2, a type of pharmaceutical preparation a medicated powder intended for internal (i.e., oral powder) or external (i.e., topical powder) use The use of medicated powders per se in therapeutics is limited Definition of granules Granules are prepared agglomerates of powdered materials, and may be used per se for the medicinal value of their content or they may be used for pharmaceutical purposes, as in tableting. The chemical and physical features of solid materials used in the preparation of pharmaceutical products 1. morphology (形态学) 2. purity (纯度) 3. solubility (溶解度) 4. stability (稳定性) 5. particle size (粒径) 6. uniformity (均一性) 7. compatibility (相容性) with any other formulation components Particle size and analysis The particle size gradation in USP Very coarse（最粗粉） Coarse（粗粉） Moderately coarse（中粉） Fine（细粉） Very fine（最细粉） This gradation system is based on sieving method（筛分法）, and is related to the proportion of powder that is capable of passing through the opening of standardized sieves of varying dimensions in a specified time period under shaking. Particle size and analysis typical particle size of granules: 4- to 12- sieve Granules fall within the range of 12- to 20- sieve are sometimes used in tablet making. The purpose of particle size analysis in pharmacy is to obtain quantitative data on the size, size distribution, and shapes of drug and nondrug components to be used in pharmaceutical formulations Particle size and analysis Particle size can influence a variety of important factors: Dissolution rate (partic