Disperse system _ Dosage form _ Pharmaceutics #emulsion #suspension #pharmacytechnician #pharmacy

Chapter 1: Liquid Phase of Pharmaceutical Dispersal Systems

Introduction

  • Discussion on dispersal systems within pharmaceuticals.

  • Overview of dosage forms where dispersion systems are applied.

Dispersal System Definition

  • A dispersal system consists of two phases:

    • Dispersed phase: the component that is spread out.

    • Dispersion medium: the phase in which the dispersed phase is spread.

  • Dispersed phase is often less in quantity compared to the dispersion medium.

  • Dispersion systems include preparations containing dissolved or non-soluble (insoluble) drugs distributed through a vehicle (solvent).

Characteristics of Phases

  • Dispersion Phase:

    • Comprised of particles that are dispersed within a medium.

    • Can be liquid, solid, or gas.

    • Example in pharmaceuticals include solid particles suspended in a liquid.

  • Dispersion Medium:

    • Typically comprises a larger amount than the dispersed phase.

    • Acts as the continuous phase surrounding the dispersed phase.

    • Can also be non-continuous in the context of other phases.

Types of Dispersal Systems**

  • Liquid Dispersal Systems:

    • When both dispersed phase and dispersion medium are liquids, common in solutions or suspensions.

    • E.g., Antibiotics prepared from powders by adding liquid as a medium.

  • Suspensions:

    • Solid particles dispersed in a liquid, e.g., an aluminum hydroxide suspension.

    • This process involves mixing solid granular materials into liquid mediums.

  • Aerosols:

    • Gas bubbles or particles dispersed within a liquid.

    • Common in personal care products, pharmaceuticals; an example includes body mists.

Particle Size Variation

  • Dispersed phase particles can vary widely in size.

  • Colloidal Particles:

    • Size ranges from 1 nanometer to 0.5 micrometers, often found in emulsions.

  • Suspension Particles:

    • Typically between 10 to 15 micrometers.

    • Relate to bigger solid or liquid particle sizes in dispersions.

Common Examples

  • Liquid Aerosols:

    • Created by dispersing liquids in gas.

    • E.g., misting sprays used in cosmetic and medical applications.

  • Solid Aerosols:

    • Solid particles dispersed in gas, referred to as powder aerosols.

  • Milk:

    • A classic example of a liquid dispersion system where fat globules (dispersed phase) are suspended in water (dispersion medium).

Summary of Table

  • Dispersed faces and their respective mediums:

    • Liquid dispersed with gas: Liquid aerosols (e.g., mists).

    • Solid dispersed with gas: Solid aerosols (e.g., powder aerosols).

    • Liquid dispersed with liquid (immiscible): Examples include milk.

Conclusion

  • The chapter's discussion provided insight into dispersion systems as crucial pharmaceutical forms.