Pharmaceutical Technology Clarification PDF

# Pharmaceutical Technology ## Clarification - Most pharmaceutical liquid preparations should be clear and free from foreign solid or liquid materials. - Clarification is the final step in the preparation of these liquid preparations. - Removal of suspended unwanted materials which might come fro...

# Pharmaceutical Technology ## Clarification - Most pharmaceutical liquid preparations should be clear and free from foreign solid or liquid materials. - Clarification is the final step in the preparation of these liquid preparations. - Removal of suspended unwanted materials which might come from raw materials, equipment, vehicles, or others. ### Factors Affecting Clarification Method Selection - **Particle size of the unwanted suspended material:** - Large particles are easily seen and removed by eye. - Small particles may require special devices. - **Physical properties of the unwanted suspended material:** - For example, removal of excess volatile oils from liquid preparations. - **Quantity of the unwanted suspended material:** - Small quantities can be removed using filtration. - Large quantities require other methods. - **Characteristics of the fluid media:** - Consider liquid viscosity, temperature effects, and exposure to air and light. - **Speed of the method:** - Faster methods are preferred over slow methods. ## Methods of Clarification ### a) Settling Method - A simple and primitive method that allows the product to stand until it separates. - Two types: - Upward settling: Suspended materials are less dense than the liquid media. - Downward settling: Suspended materials are denser than the liquid media. - **Factors affecting settling:** - Rate of settling (dx/dt) - Diameter of particles (d) - Density of particles (pi) - Density of medium (pe) - Gravitational constant (g) - Viscosity of medium (η) - **Centrifuge clarification:** - Accelerates settling by changing the gravitational constant. ### b) Filtration and Percolation Method - **Percolation:** - Simple filtration through a piece of cotton or cloth. - **Filtration:** - More advanced technique involving passing through a filter media, like filter paper. - **Factors affecting filtration rate:** - Viscosity of liquid medium - Size and shape of suspended particles - Aim of filtration (clear liquid or other) - Surface area (A) - Viscosity of medium (η) - Thickness of cake layer (I) ### Types of Filter Media - **Sheets of woven materials:** Cotton, wool, or filter papers. - **Porous plates:** Made from stones, ceramic, or glass with different pore sizes. - **Membrane filter:** Made from cellulose or its derivatives with different pore sizes. - **Unwoven fibrous materials:** Used for simple clarification. - **Granular or powdered materials:** Sand, charcoal, or any other inert material. - **Ultrafilter and microsieve:** Separate micro-organisms and very small particles. ## Elixirs - Clear hydroalcoholic solutions intended for oral use. - Usually sweetened and flavored to enhance palatability. - Non-medicated elixirs: Used as vehicles. - Medicated elixirs: Used for therapeutic effects. ### Properties of Elixirs - **Less Viscous than Syrups:** Due to lower sugar content. - **Less Sweet than Syrups:** Due to lower sugar content. - **Better than Aqueous Syrups:** Maintain both water-soluble and alcohol-soluble components. - **Easy to Prepare:** Simple solution method. - **Variable Alcohol Content:** Depends on the solubility of the components. ### Sweetening Agents for Elixirs - **Sucrose or sucrose syrup** - **Sorbitol** - **Glycerin** - **Artificial sweeteners:** Saccharin ### Components of Elixirs - **Flavoring agents:** Enhance palatability. - **Coloring agents:** Enhance appearance. ### Self-Preservation of Elixirs - Elixirs containing more than 10% alcohol are usually self-preserving and do not require an antimicrobial agent. ### Dosage of Medicated Elixirs - Formulated to provide the usual adult dose in a convenient measure. - Usually one or two teaspoonfuls (5 or 10 mL). ### Advantages of Elixirs - **Flexible dosage:** Easy to administer to patients who have difficulty swallowing solid forms. ### Disadvantages of Elixirs - **Alcoholic content:** May be unsuitable for children or adults who avoid alcohol. ### Storage of Elixirs - Store in tight, light-resistant containers and protect from excessive heat. ## Preparation of Elixirs - Simple solution with agitation or by admixture of liquid ingredients. - **Alcohol-soluble materials:** Dissolved in alcohol. - **Water-soluble components:** Dissolved in purified water. - **Add aqueous solution to alcoholic solution:** Maintain the highest possible alcoholic strength. - **Final volume:** Made up with the specified solvent or vehicle. - **Cloudy mixture:** May occur due to separation of flavoring oils. Permit to stand for several hours to separate the oil globules. - **Talc filter aid:** Absorbs excessive amounts of oils. ## Nonmedicated Elixirs - **Uses:** - Addition of a therapeutic agent to a pleasant-tasting vehicle. - Dilution of an existing medicated elixir. ### Nonmedicated Elixir Selection - **Solubility and stability:** Of the drug substance. - **Alcoholic concentration:** Similar to the medicated elixir to be diluted. - **Flavor and color:** Should not conflict with the medicated elixir. - **Compatibility:** All components should be chemically and physically compatible. ### Common Nonmedicated Elixirs - Aromatic elixir - Compound benzaldehyde elixir - Isoalcoholic elixir ## Medicated Elixirs - Employed for the therapeutic benefit of the medicinal agent. ### Antihistamine Elixir - **Uses:** Symptomatic relief of allergic disorders. - **Mechanism of action:** Suppress symptoms caused by histamine. - **Side Effect:** Sedation. - **Warning:** Avoid activities requiring mental alertness. - **Other adverse effects:** Dryness of nose, throat, and mouth; dizziness; and disturbed concentration. ### Barbiturate Sedative and Hypnotic Elixirs - **Uses:** Produce various degrees of central nervous system depression. - **Effects:** Sedation, hypnosis, respiratory depression (in high doses). - **Dosage:** - Small doses: Sedation, daytime use. - Larger doses: Hypnotics, bedtime use. - **Classification:** - **Long-acting:** Maintain daytime sedation. - **Intermediate-acting and short-acting:** Treat insomnia. - **Ultra-short-acting:** Induce anesthesia. - **Side Effect:** Drowsiness, lethargy. - **Prolonged use:** May lead to psychic or physical dependence. ## Digoxin Elixir - **Properties:** Cardiotonic glycoside, insoluble in water but soluble in dilute alcohol. - **Alcohol Content:** About 10%. - **Dosage:** Carefully determined for each individual patient. - **Available Dosage Forms:** Tablets and elixir. - **Elixir Use:** Children. - **Importance:** Dosage forms may exhibit different bioavailability characteristics. ## Spirits - **Definition:** Alcoholic solutions of volatile substances. - **Alcohol Concentration:** Usually over 60%. - **Solubility:** Greater solubility of volatile substances in alcohol than in water. - **Preparation:** Mixing with water or aqueous preparation forms milky preparation due to separation of volatile substances. - **Uses:** - **Flavoring agents** - **Therapeutic value of the aromatic solute** ### Common Spirits - Aromatic ammonia spirit. - Camphor spirit. - Compound orange spirit. - Peppermint spirit.