Physical Pharmaceutics

BP206T :

Physical Pharmaceutics (Theory)

COURSE OBJECTIVES

The objectives of this course are to:

1. Provide a comprehensive understanding of the theory and principles of pharmaceutical processes and unit operations involved in drug manufacturing.

2. Impart knowledge of physicochemical phenomena such as solubility, dissolution, interfacial phenomena, rheology, and micromeritics relevant to dosage form design.

3. Develop understanding of colloidal and coarse dispersions, including suspensions and emulsions, and their pharmaceutical applications.

4. Familiarize students with rheological and micromeritic properties of powders and dispersions and their role in formulation development and evaluation.

5. Build a strong foundation for formulation development, process optimization, and quality control of pharmaceutical dosage forms.

Course Outcomes (CO):

Upon successful completion of this course, the students will be able to:

1. Explain and interpret the fundamental principles governing pharmaceutical manufacturing processes and unit operations.

2. Analyze physicochemical properties of drugs and excipients and correlate them with formulation stability, quality, and performance.

3. Apply concepts of interfacial phenomena, colloids, and dispersions in the design and evaluation of pharmaceutical dosage forms.

4. Evaluate and optimize pharmaceutical processes by controlling variables related to rheology, micromeritics, and dispersion systems.

5. Demonstrate foundational competency required for advanced studies in formulation

development, industrial pharmacy, and pharmaceutical research.

Detailed Syllabus:

Unit I

Solubility distribution phenomenon & buffers

Solubility expression, Solute solvent interactions, Solubility of liquid and liquids, Solubility of solids and liquids, Solubility of Gas in Liquids, Raoult’s Law. Factors affecting solubility, Measurement of saturation Solubility, Effect of pH on solubility, Partition Coefficient – Measurement and significance, Critical Solution Temperature and Applications.

Introduction to buffers, Buffers in pharmaceutical and biological system, pH determination methos (Electrometry and colorimetry). Buffer equation / Factor influencing the pH of buffer solutions, Factor influencing Buffer capacity, General procedure for preparing buffers, Indicators.

Unit II

Interfacial phenomenon

Liquid interface: Surface and interfacial tension, surface free energy, Measurement of surface and interfacial tension, Spreading coefficient, surface active agent, HLB, detergency, types of monolayers at liquid surface. Adsorption at solid interface, Liquid Interface (contact angle, activated charcoal and Wetting). Adsorption of surface-active agents. Electric properties of interface / Electric double layer, Nernst and zeta potential effect of electrolytes

Unit III

Colloidal and Coarse Dispersion

Colloidal dispersions: Types of colloidal dispersions (Lyophobic, Lyophilic, Association colloids), Optical properties of colloids, Kinetic properties of colloids, Electrical properties of colloids, Size and shape of colloidal systems, Stability of colloidal system (peptization and protective action), Application of Colloidal System.

Coarse Dispersions: Suspensions, stokes law (Theory of sedimentation), Effect of Brownian movement / Sedimentation of flocculated particles, sedimentation parameters. Flocculation and controlled structure flocculation. Theories of emulsification and stabilizaition (DLVO Theory, Monomolecular adsorption, Multimolecular adsorption, Film formation, Solid particle adsorption). Physical instabilities of emulsions (creaming, coalescence and breaking, and phase inversion).

Unit IV

Rheological studies

Newtonian systems and non-Newtonian systems. Thixotropy – measurement / Bulges and spurs. Negative thixotropy, Determination of rheological properties (Viscometers / single and multi-point).

Viscoelasticity, psycho-rheology. Applications of rheology in pharm

Unit V

Micromeritics

Particle size and size distribution, Particle Shape and Surface area: Methods for determination and significance. Flow properties of powders: determination, significance and methods of enhancement. Advanced flow properties of powers (Powder flow tester).

Recommended References (Preferably latest editions):

1. Sinko, P.J., Martin's Physical Pharmacy and Pharmaceutical Sciences.

2. Allen, L.V. and McPherson, T.B., Ansel's Pharmaceutical Dosage Forms and Drug Delivery Systems.

3. Adejare, A., Remington: The Science and Practice of Pharmacy.

4. Aulton, M.E. and Taylor, K.M.G., Aulton Pharmaceutics: The Design and Manufacture of Medicines. Elsevier.

5. Lachman, L. and Libbermann, H.A., The Theory and Practice of Industrial Pharmacy.

Mendham, J., Denney, R.C., Barnes, J.D. and Thomas, M.J.K., Vogel's Textbook of

6. Quantitative Chemical Analysis.

Myers, D., Surfaces, Interfaces, and Colloids: Principles and Applications. Ladisch, M.R., Rheology of Fluid and Semisolid Foods. Springer.