Introduction to Emulsions and Types of Emulsions.pptx

This Presentation is about Emulsions .An emulsion is a type of mixture formed by combining two immiscible liquids, where one liquid is dispersed in the other. These mixtures are stabilized through the use of emulsifiers, which are agents that prevent the separation of the two phases by reducing the surface tension between them.

1. EMULSIONS

2. EMULSIONS E mulsion refers to a type of dispersed system consisting of two immiscible liquids, typically oil and water, stabilized by the addition of an emulsifying agent.

3. E mulsifying agent. . Emulsifying agents are the substance added to an emulsion to prevent the coalescence of the globules of the dispersed phase. They are also known as emulgents of emulsifiers. They act by reducing the interfacial tension between the two phases and forming a stable interfacial film.

4. TYPES OF EMULSION Water-in-oil (W/O) O il-in-water (O/W), C omplex emulsions such as water-in-oil-in-water (W/O/W).

5. Difference between (W/O) and (O/W) Emulsion Water in Oil Emulsion Oil is the dispersion medium and water is the dispersed phase. Greasy and not water washable Used externally to prevent evaporation of moisture from the surface of skin e.g. Cold cream Preferred for external use like creams. Oil in Water Emulsion 1. Water is the dispersion medium and oil is the dispersed phase 2. Non greasy and easily removeable from the skin 3. Used externally to provide cooling effect e.g. vanishing cream 4. Preferred for internal use as bitter taste of oils can be masked.

6. Test for Identification of Type of Emulsion Dilution test Conductivity test Dye solubility test Cobalt chloride test Florescence test

7. Dilution test This test can be conducted by adding water or oil to the emulsion.

8. Conductivity test Water is a good conductor of electricity whereas Oil is non-conductor. Therefore, continuous phase of water runs electricity more than continuous phase of oil.

9. Dye solubility test In this test ,when emulsion is mixed with a water dye such as amaranth and observed under microscope, If the continuous phase appears red then it means that the emulsion is O/W type. If the discontinuous phase appears red and continuous phase is colorless then it is W/O emulsion.

10. Cobalt chloride test Filter paper soaked in cobalt chloride solution and allowed to dry. The filter paper will turns from blue to pink on exposure to O/W emulsion.

11. Methods for the preparation of Emulsions

12. Florescence test Oil gives florescence under UV light, while water doesn’t. Therefore, O/W emulsion shows spotty pattern when observed under UV. While W/O emulsion shows continuous florescence. W/O Emulsion O/W Emulsion