presentation

1. MUCOADHESIVE MICROSPHERE
Presented by,
Pallab Kumar Pal
M.Pharm, 1st year (Pharmaceutics)
Roll no. 02
Under the guidance of,
Dr. Somasree Ray
Professor (Department of Pharmaceutics)
Gupta College of Technological Sciences

2. Introduction
Microspheres are microscopic hollow spherical micro particles, especially of a
protein or polymer
The term bioadhesion refers to any bond formation between biological surfaces
or a bond between biological and synthetic substance
If the biological surface is mucus bioadhesion is termed as mucoadhesion

3. Structure of mucous membrane

4. Mechanism of mucoadhesion
Mucoadhesion is a complex phenomenon, which involves wetting, adsorption, and
interpenetration of polymer chains.

5. Characteristics
of an ideal
mucoadhesive
polymer
High
molecular
weight up to
100000 or
more Long chain
polymer
High
viscosity
Degree of
cross linking
Spatial
conformation
Flexibility
of polymer
chain
Concentration of
polymer
Charge and
degree of
ionization
Optimum
hydration

6. Examples of
mucuadhesive
polymers
Natural
i. Chitosan
ii. Sodium alginate
iii. Pectin
iv. Locust bean gum
v. Guar gum
vi. Xanthan gum
vii. Karaya gum
viii. Gelatin
ix. Tragacanth
x. Soluble starc
Synthetic
i. HPMC
ii. PVP
iii. PVA
iv. Poly hydroxy methyl methacrylate
v. Polyethylene oxide
vi. Na CMC
vii. HEC
viii. HPC
ix. EC
x. Polyacrylates

7. Methods of preparation
1. Phase separation coacervation technique
2. Emulsion cross-linking method
3. Solvent evaporation method
4. Spray drying method
5. Ionotropic gelation method

8. 1. Phase separation coacervation technique
Drug dispersed
in polymer (I)
Incompatible
polymer (II)
added
Phase
separation of
polymer (I) and
engulfment of
drug
Addition of non-
solvent
Solidification of
polymer

9. 2. Emulsion cross-linking method
Drug dissolved in
previously heated
(40°C,1h) aqueous gelatin
solution
This, drop wise added to
liquid paraffin with cont.
stirring (1500rpm, 10mins,
35°C)
w/o emulsion formed and
this is further
stirred(15°C, 10 mins)
Microspheres produced
and washed respectively
with acetone and
isopropyl alcohol
Air dried microspheres dispersed in
aqueous glutaraldehyde saturated
toluene solution for crosslinking
It is then treated with glycine
solution containing 0.1%w/v of
tween 80 to block unreacted
glutaraldehyde

10. 3. Solvent evaporation method
Core material mixture dispersed in
the liquid manufacturing vehicle
phase to obtain the appropriate size
microcapsule
Evaporation
of solvent
Polymer shrinks
around the core

11. 4. Spray drying method
Polymer dissolved in a
suitable volatile organic
solvent (dichloromethane,
acetone, etc)
Drug in the solid form
dispersed in the polymer
solution under high-speed
homogenization
Formation of the small
droplets or the fine mist
Formation of the
microspheres

12. 5. Ionotropic gelation method
Drug+Aqueous
solution of gel-type
polymer
This mixture dropwise
added to the solution of
crosslinking agent
Microspheres are
formed

13. Evaluation parameters
1. Particle size
2. Shape and surface morphology
3. Drug entrapment efficiency
4. Percentage yield
5. Degree of swelling
6. Mucoadhesion test
7. Compatibility study (DSC, HPLC)
8. Drug release study

14. Advantages and disadvantages
Advantages
i. Controlled release for longer period of
time
ii. Frequency is reduced and hence patient
compliance is increased
iii. Constant release and hence no peaks and
troughs in concentration of drug
iv. Low dose and hence toxic effect is less
v. Targeting the tissue is possible
vi. Other organ toxicity is less
Disdvantages
i. Difference in the release rate can be
found from one dose to another
ii. The release rate may vary from a variety
of factors like the rate of transit, food
through gut, etc.
iii. Any loss of integrity in release pattern
of the dosage form may lead to potential
toxicity
iv. These types of dosage forms cannot be
crushed or chewed
v. The release from the formulations may
get modified.

15. Application
Controlled and
sustained
release
Hygroscopic
properties
of many core
materials
may be reduced
Reduce
gastric
irritation
Exhibit a
prolonged
residence time at
the site of
application

16. Conclusion
Novel drug delivery systems achieved a great interest in recent years in the field of
modern pharmaceutical formulations. Mucoadhesive microspheres have been proved as
a promising tool in delivery of drugs to a particular site in controlled manner, as they
deliver the drug to a particular site for longer duration, the absorption of drug increased
and hence, the bioavailability of the drug get increased. Therefore, it can be said that in
future also mucoadhesive microspheres will play an important role in the development
of new pharmaceuticals employing more advanced techniques and materials.