Bioisosterism Definition: Bioisosterism are structurally similar chemical groups that mimic the biological activity of another. Importance in Drug Design: Improved Activity: Replacement of groups can enhance potency and reduce toxicity. Increased Stability: Bioisosteres improve metabolic stability. Reduced Side Effects: Modification helps improve drug safety. Examples: Sulfonamide (-SO₂NH₂) as a bioisostere of carboxyl (-COOH) in diuretics. Fluorine … Read more
Size of capsules refers to the standardized dimensions of empty capsules, indicating their volume capacity. They range from 000 (largest) to 5 (smallest), used to encapsulate varying drug doses. Size of capsules determines the fill weight and patient compliance. Proper size selection ensures accurate dosing, ease of swallowing, and suitability for the intended formulation. Soft … Read more
Chelation Definition: Chelation is the formation of complexes between drugs and metal ions (e.g., Ca²⁺, Fe³⁺, Mg²⁺). Importance in Drug Action: Drug Absorption: Chelating with dietary minerals reduces absorption (e.g., tetracyclines + calcium). Toxicity Management: Chelating agents are used to remove heavy metals (e.g., lead, arsenic). Stability: It can enhance or reduce drug stability in … Read more
Manufacturing Defects in Capsules: Include cracks, deformation, or uneven thickness. Manufacturing Defect in Tablets: May involve chipping, capping, or hardness issues. Causes: Poor materials, machinery faults, or improper handling. Hard gelatin capsules can exhibit defects during production or filling, such as: Cracks: Caused by improper drying or excessive brittleness of gelatin. Deformation: Due to improper … Read more
Protein Binding Definition: Protein Binding: Drugs bind to plasma proteins (e.g., albumin, globulins) in the bloodstream, affecting their distribution and activity. Importance in Drug Action: Free vs. Bound Drug: Only free drug is active; bound drug serves as a reservoir. Drug-Drug Interactions: Competition for binding sites can increase free drug concentration and toxicity. Duration of … Read more
Hydrogen Bonding Definition: Hydrogen bonding occurs when hydrogen (H) atoms interact with electronegative atoms (O, N, F). This contributes to a drug’s solubility and receptor binding. Importance in Drug Action: Water Solubility: More hydrogen bonds = better water solubility. Receptor Binding: Hydrogen bonds enhance drug-receptor interactions (enzyme active sites, DNA intercalation). Stability: Hydrogen bonds stabilize … Read more
Nature of Shell and Capsule Content includes gelatin or non-gelatin materials that form the outer shell, designed for stability, protection, and ease of swallowing. Nature of Shell and Capsule Content also refers to the inner content—liquids, powders, granules, or semi-solids—formulated for accurate dosing and targeted drug release. Nature of the Shell: Soft gelatin capsules (soft … Read more
Partition Coefficient Definition: The partition coefficient (P) is the ratio of a drug’s solubility in lipid (oil) vs. water. It is often expressed as log P, which quantifies lipophilicity. $P = \frac{\text{Concentration in lipid phase}}{\text{Concentration in aqueous phase}}$ High log P (>3): Lipophilic (fat-soluble) Low log P (<1): Hydrophilic (water-soluble) Optimal log P (~1-3): Good … Read more
Soft gelatin capsules (soft gels) are a specialized form of capsules made from a single, pliable shell that encapsulates liquid or semi-solid formulations. Soft gelatin capsules are widely used in the pharmaceutical, nutraceutical, and cosmetic industries for delivering active pharmaceutical ingredients (APIs), oils, or other bioactive compounds. Key Features of Soft Gelatin Capsule: Composed of … Read more
Solubility Definition: Solubility is the ability of a drug to dissolve in a given solvent (e.g., water, lipids, organic solvents). Drugs must dissolve in biological fluids before they can be absorbed and exert their effect. Importance in Drug Action: Oral Bioavailability: Poorly soluble drugs have lower absorption and bioavailability. Drug Formulation: It determines the formulation … Read more
