Microencapsulation, Definition Need of Microencapsulation Advantages Fundamental consideration Techniques Applications

1. PRESENTED BY: Riteksha Patel
M.Pharma (pharmaceutics)

2.  Definition
 Need of Microencapsulation
 Advantages
 Fundamental consideration
 Techniques
 Applications
 References

3. DEFINITION: A process by which solid , droplets of liquid and
dispersion can be enclosed in microscopic particle by the formation
of thin coating of wall material around the substance.
INTRODUCTION
Core material Wall material
Coating

4. NEED OF MICROENCAPSULATION:
Entrapment of a material inside microparticles for
 immobilized it
 protect it
 release it
 structure it

5.  To Increase of bioavailability.
 To alter the drug release.
 To produce a targeted drug delivery.
 To protect the core from outside environment.
 To decrease evaporation rate of the volatile core material.
 To convert liquid into solid form.
 To mask the core taste.
 Protects the GIT from irritant effects of the drug.

6. FUNDAMENTAL CONSIDERATION:
Core material Coating material Vehicle
Solid Liquid
Microencapsulation
Polymers
Waxes
Aqueous No aqueous
Resins
Proteins
Polysaccharides

7.  The material to be coated.
 It may be liquid or solid in nature.
 Liquid core may be dissolved or dispersed material.
COMPOSITION OF CORE MATERIAL:
 Drug or active constituent
 Additive like diluents
CORE MATERIAL:

8. IDEAL CHARACTERISTICS:
 Capable of forming a film cohesive with core material.
 It should be compatible with the core material.
 It Should be stable, non reactive.
 Provide desired coating properties like strength, flexibility&
impermeability.
COMPOSITION OF COATING:
 Inert polymer
 Plasticizer
 Coloring agent
COATING MATERIAL:

9. 1. MICROENCAPSULATION TECHNIQUES:
1. Air suspension technique (Wurster)
2. Coacervation-Phase separation process
3. Spray drying & spray congealing
4. Multiorifice Centrifugation Process
5. Pan coating
6. Solvent evaporation
7. Polymerization
8. Nozzle vibration technology
9. Jet cutter technology
10. Extrusion
11. Single & double emulsion techniques
12. Supercritical fluid anti solvent method (SAS)

10. 10
MICROENCAPSULATION PROCESSES &
THEIR APPLICABILITIES:

11. 1.WURSTER PROCESS:

12. Polymeric
Membrane
Droplets
Homogeneous
Polymer Solution
Coacervate
Droplets
PHASE
SEPARATION
MEMBRANE
FORMATION
1.Formation of three immiscible phases
2.Deposition of coating
3.Rigidization of coating

14.  Used for large size particles i.e. 600-5000 μm size.
 Coating pan is used for this operation.
 Coating solution is applied as a solution or atomized
spray on sugar pellets (Non-pareil sugar seeds).
 Warm air is passed to remove the coating solvent.

16. Polymer
+ Volatile organic solvent
Organic Polymeric Phase
Formation of Oil-in-Water
Emulsion
Solvent Evaporation
Particle Formation by Polymer
Precipitation
RECOVERY OF POLYMERIC
MICROPARTICLES
Temperature increase
Active Ingredient
Addition into an aqueous
phase (+o/w stabilizer)
5.SOLVENT
EVAPORATION:

17. 6.SPRAY DRYING & CONGEALING :
Spray drying : spray = aqueous solution / Hot air
Spray congealing : spray = hot melt/cold air

18. 7.POLYMERIZATION:
Method developed by Chang
Interfacial polymerization..
Aliphatic diamine Dicarboxilic acid halide
Liq- Liq. interface
polymerization Microspheres

19. (D) Vibration technology
•This technology is based on an ancient principle (Lord
Rayleigh, in the late 19th century) which shown that a
laminar liquid jet breaks up into equally sized droplets by
a superimposed vibration. The parameters are the
frequency, the velocity of the jet and the nozzle diameter.
•To guarantee the production of uniform beads or
capsules and to avoid large size distributions due to
coalescence effects during the flight, the droplets pass
through an electrostatic field to be charged. As a result
these droplets don’t hit each other during the flight and
will be spread over a larger surface of the gelation bath
thus resulting in monodisperse beads.

21. (E) JetCutter technology
The JetCutter is a simple technology for bead production that meets
the requirement of producing monodisperse beads originating from
low up to high viscous fluids with a high throughput `

23. APPLICATION OF MICROENCAPSULATION:

24. ADVANTAGE OF MICROENCAPSULATION
• administered dose of a
drug is subdivided into
small units that are
spread over a large area
of the gastrointestinal
tracts, which may
enhance absorption by
diminishing local drug
concentration
• Micro-K ExtenCaps

25.  Its costly process, not economical.
 More skill is required.
 It is difficult to get continuous & uniform film.

26. 1.Microcapsules: The active agent forms a core surrounded by an
inert diffusion barrier.
2.Microspheres: The active agent is dispersed or dissolved in an
inert polymer.

28.  Stability testing
 Size of microcapsules- Sieving Method
 Amount of drug present In microcapsules
 Dissolution test- Invitro drug release

29.  Leon, L., Herbert A. L., Joseph, L. K; “ The Theory And
Practice Of Industrial Pharmacy”, 3rd edition (1990),
Varghese Publishing House, Page no. 412-428.
 Vyas S.P, Khar R.K; “Targeted & Controlled drug
delivery ’’ Novel carrier systems,1st
edition (2002),CBS
publisher & distributors New delhi, page no.418-455.
 Wise D.L, “Handbook of pharmaceutical controlled
release technology”1st
edition , Marcel Dekker New York,
page no. 271-286,