advantages disadvantages and method of Microencapsulation.pptx

1.Introduction.�2.Advantages.�3.Disadvantages.�4.Methods.of microencapsulation
Microencapsulation by air suspension
method consists of the dispersing of
solids, particulate core materials in a
supporting air stream and the spray
coating on the air suspended particles
Within the coating chamber, particulate
core materials are suspended on an
upward moving air stream.

1. Microencapsulation Presented By : Divya Dhule M.Pharm 1 st Year (Pharmaceutical Chemistry) Department of Pharmaceutical Sciences Rashtrasant Tukadoji Maharaj Nagpur University,Nagpur

2. Content : 1.Introduction. 2.Advantages. 3.Disadvantages. 4.Methods .

3. Introduction Definition: The process by which individual particals or droplets of solid or liquid material are surrounded or coated with continuous film of polymeric material to produce microcapsules . Microcapsule / Micosphere : size of particle from micrometer to millimeter i.e. 1-1000 micrometer .

4. A dvantages : Mask the bitter taste Decrease irritation To prevent acid degradation Increase solubility stabilisation of core material Hygroscopic drug is used

5. Disadvantages: 1.It is costly method. 2.More skill is required. 3.it is difficult to continuos and uniform film.

6. Methods of Microencapsulation

7. Air suspension/ wruster Process: Microencapsulation by air suspension method consists of the dispersing of solids, particulate core materials in a supporting air stream and the spray coating on the air suspended particles Within the coating chamber, particulate core materials are suspended on an upward moving air stream.

8. 2 .Multiorifice Centrifugal Method: The Southwest Research Institute (SWRI) has developed this method.It is a mechanical process for producing microcapsules. Centrifugal forces are used to hurl a core material particle through an enveloping microencapsulation membrane.

9. 3.Coacervation Phase separation Method: Coacervation means the separation of a liquid or phase when solution of two hydrophilic colloids are mixed under suitable conditions. In this method, the three immiscible phases of core material, solvent and coating material are formed followed by deposition of coating material on the core. The coating material is dissolved in a suitable solvent and the core material is uniformly dispersed in the solution of the coating material. Then the coating material is phased out of its solution which starts getting deposited on the particles of the core material.

10. 4.Pan Coating Method: Pan coating is a physical method of preparing microencapsulation and it can only be used for particles greater than 600 microns in diameter. Process of microencapsulation by pan coating 1.Solid particles are mixed with a dry costing material. 2.The temperature is raised so that the coating material melts and encloses the core particles, and then is solidified by cooling Or the coating material can be gradually applied to core particles tumbling in a vessel rather than being wholly mixed with the core particles from the start of encapsulation.

11. 5.Solvent Evaporation Method: Solvent evaporation techniques are carried out in a liquid manufacturing vehicle (O/W emulsion) which is prepared by agitation of two immiscible liquids. The process involves dissolving microcapsule coating(polymer) in a volatile solvent which is immiscible with the liquid manufacturing vehicle phase. A core material (drug) to be microencapsulated is dissolved dispersed in the coating polymer solution.

12. 6.Spray Drying And Congealing Method: Spray Drying : The coating solidification effected by rapid evaporating of solvent in whichcoating material is dissolved. Spray Congealing : The coating solidification is effected by thermally congealing a molten coating material. The removal of solvent is done by sorption, extraction or evaporation technique

13. Reference: The Theory and Practice of Industrial Pharmacy, lachman / lieberman , 4th edition, pg no. 579-596 Microencapsulation- Processes and Applications, edited by Tan E. Vandegar , pg no. 1-20 and 57-59 Multiparticulate drug delivery, edited by lisaac Ghebre- Sellassie , pg no. 51-109 The Design and Manufacture of Medicines, Michael Aulton and Kevin M.G.Taylor , 4th edition, pg no. 578-581 Polymeric Drug Delivery- Particulate Drug Carriers, edited by Sonke Svenson, pg no. 242-245