This document discusses nanoparticles, including their definition as submicron colloidal structures composed of polymers that are 10-1000nm in size. Nanoparticles can be nanospheres or nanocapsules and are used to deliver drugs through various routes of administration. They provide benefits like site-specific delivery and increased therapeutic effects with fewer side effects compared to traditional therapies. However, nanoparticles also have challenges such as low drug loading and the potential for particle aggregation. The document also reviews various polymers, preparation methods, and evaluation techniques used for nanoparticles.
3. Nanoparticles : Nanoparticles is derived from
the greek word nano
nano means extremely small.
4. DEFINITION: “Nanoparticles are subionized
colloidal structure composed of synthetic (or)
semisynthetic polymers.”
Size range: 10 – 1000nm.
The drug is dissolved ,entrapped , encapsulated
(or) attached to a nanoparticle matrix.
The materials which are used for the
preparation of nanoparticles should be non-
toxic, biodegradable, sterlizable etc.,
5. Nanospheres: Nanospheres are matrix systems
in which the drug is physically and uniformly
dispersed.
Nanocapsules: Nanocapsules are systems in
which the drug is confined to a cavity
surrounded by a unique polymer memebrane.
6. Site-specific delivery of drugs.
Nanoparticles helps to achieve maximum
therapeutic response with minimum adverse
effects.
Active and passive drug targeting can be
achieved by manipulating the particle size and
surface characteristics of nano particles.
Nanoparticles can be administrated by parentral,
oral, nasal (or) occular routes.
By attachig specific ligands onto their
surfaces,nanparticles can be used for directing
the drugs to specific target cells.
7. Limited drug loading.
Susceptible to bursting and leakage of contents.
Small size and large surface area can be lead
to particle aggregation.
Handling of nanoparticles is difficult in liquid
and dry forms.
8. Preparation methods
ofnanoparticles
SUPER CRITICAL
FLUID
1.Rapid
expansion super
critical fluid.
2.Super critical
anti solvent
PERFORMED
POLYMER
1.Solvent
evaporation
method.
2.Solvent
displacement
method.
3.Salting out
method
POLYMERIZATION
1.Interfacial
polymerization
2.Dispersion
polymerization
3.Emulsion
polymerization
9. 1. Size of nanoparticles required.
2. Inherent properties of the drug.
3. Surface characteristics such as charge and
permiability.
4. Degree of biodegradability, biocomptability
and toxicity.
5. Drug release profile desired.
6. Antigenicity of the final product.
19. Nano-Particles are evaluated by the fallowing
methods. They are:
Particle size.
Surface area.
Surface charge.
density.
Molecular weight.
Nano-particle yield.
Drug entrapment efficiency.
Invitro release.
20. Particle size:
1. Both the particle size and size distribution
are the important parameters that governs
the stability, drug loading and rate of drug
release.
Various techniques are involved in the
determination of particle size and surface
distribution.
a. Photon correlstion spectroscopy.
b. Electron microscopy.
c. Scanning electron microscopy.
21. d. Transmission electron microscopy
e. Freeze – fracture technique.
F. Atomic force microscopy.
Surface area: An instrument spectrometer is used
to determine the specific surface area of
nanoparticles. The specific surface area can be
caluclated from the fallowing equation,
Where,
A= specific surface area of nanoparticles.
d = diameter of the nanoparticles.
22. Suface charge:of the nano particles is given in
terms of zeta potential,which is indicative
of their electrical properties.
2. Surface charge of nanoparticles is dependent
upon their composition and on the medium of
dispersion.
3. It is measured by zetapotential.
4. The value of zeta potential above +-30mv for
nanoparticles is found to be ideal.
23. Density: The density of the nanoparticles can be
determined by gas pycnometer. The density
distribution across the matrix of the nanoparticles can
be obtained from structural imperfections.
24. Molecular weight: molecular weight of
nanoparticulate polymer can be determined
by gel permiation chromatography by
utilizing a refractive index detector.
Nanoparticle yield: nanoparticle yield is
given in terms of %
25. Drug entrpment efficiency:
loading of drug in nanoparticles is given by
fallowing equation:
26. a. Incorporating the drug during the
formulation of nanoparticles.
b. Incubating the formed nanoparticles with
concentrated drug solution.
Invitro release: invitro drug release from the
nanoparticles can be determined by
a. diffusion cell.
b. ultra filtration.
27.
28.
29. Delivery of Anti-cancer drugs.
Nanoparticls have been found to accumulate
in tumors after IV administration.
Reduction in toxicity of Anti-cancer drugs as
drugs are concentrated mainly in liver and
spleen.
Useful in treatment of hepatic metastases.
OCCULAR DELIVERY: Nanoparticles with
steroids, anti-inflammatory agents, and
bacterial agents for glaucoma in order to
improve retention of drug/ reduced wasah
out.
30. VIRAL INFECTIONS: Nanoparticles represent
an interesting for selective transport of anti-
viral agents displaying poor selectivity or
short plasma half-life.
Eg: nanoparticles loaded with protease
inhibitor sesquineir was shown to be
effective in HIV infected human macrophage
cultures.
Vaccine Adjuvent: Increase immune
response, alternate acceptable adjuvant
material nanoparticles with vaccines.
31. N.k.jain controlled and novel drug delivery .,
CBS publishers and distribution , new delhi,
first edition 1997.
Nanoparticles-A review by vj mohan raj and
chen y, tropical journal of pharmaceutical
research in 2006.