Surface and Interfacial tension [Part-6]�( Solubilization, Detergency, Adsorption at solid interface )�

Solubilization: Detergency, Adsorption at solid interface

1. IIIrd Semesester B. pharmacy Physical Pharmaceutics-I Unit-III Surface and Interfacial tension [Part-6] ( Solubilization, Detergency, Adsorption at solid interface ) Miss. Pooja D. Bhandare (Assistant professor) Kandhar college of pharmacy

2. Solubilization It is the process in which, solubility of organic compound is increased in aqueous medium with the help of surface active agents (surfactant), this phenomenon is know as solubilization. It is used in many industries for the mixing of two immiscible liquids and help in making of drug.

3. Detergency It is the process or phenomenon in which dirt ( aid and solid object) remove from the surface with the help of detergent. Find these detergent are basically made up with surfactant or itself surfactant. It whole that, it reduce the adhesive force, so dirt particle easily remove from the surface.

4. Adsorption at solid interface When substance (material) deposit on the surface of solid is called the adsorption at solid interface. Thus material (substance) which deposit on the surface of solid is called adsorbate. The material (substance) on whose surface the process take place is called adsorbent.

5. Adsorption of a gas or a liquid onto a solid surface is important in pharmacy. The degree of adsorption of gas by a solid depends on the Nature od adsorbent and its surface area Nature of adsorbate and the partial pressure of gas Temperature

6. Depending on the nature of interaction, adsorption is classified into physisorption (physical adsorption) and chemisorption (chemical adsorption). The difference between physical and chemical adsorption are as follow.

7. Physical adsorption Chemical adsorption Reversible Irreversible Weak van der wall forces Strong chemical bond Hydrogen bonding and weak electronic Covalent bond Nonspecific More specific Common in low temperature Occurs in high temperature Heat of adsorption is low (20 to 40 kj /mol) Heat of adsorption is high (40 to 400 kj / mol) Example is adsorption of gases or charcoal Examples are adsorption of oxygen on silver or gold

8. Thank you!