This document discusses methods for preparing polymeric nanoparticles. There are two main types of polymers used: natural hydrophilic polymers like proteins and polysaccharides, and synthetic lipophilic polymers that are either pre-polymerized or polymerized during preparation. The main preparation methods are amphiphilic macromolecule cross-linking using heat or chemical cross-linkers, polymerization-based methods involving emulsion, dispersion, or interfacial condensation polymerization, and polymer precipitation methods using solvent extraction/evaporation, solvent displacement, or salting out. Common techniques include single or double emulsion followed by solvent evaporation to create drug-loaded nanoparticles.

1. Preparation methods of polymeric nanoparticles
polymers used in preparation:
1- Natural hydrophilic eg. Proteins & poly saccharides
a) Proteins :
Gelatin
Albumin
Lectin
Legumine
Viciline
b) Poly saccharides :
Alginate
Dextran
Chitosan
Agarose
Pullulan
Preparation methods of polymeric nanoparticles
By: ph Abeer Abd elrahman

2. 2-Synthetic lipiphilic eg. Pre-polymerized & polymerized in process
a) Pre-polymerized :
Poly E caprolactone
PLA
Poly lactide co glycolide (PLGA)
Polystyrene
b) Polymerized in process:
Poly Isobutyrl cyano acrylates (PICA)
PBCA
PHCA
Poly methyl methacyrlate (PMMA)

3. Methods of preparation:
1- Amphiphilic macromolecule cross-linking :
a) heat cross linking
b) chemical cross linking.
2- Polymerization based methods :
polymerization of monomers
a) Emulsion polymerization
b) Dispersion polymerization
c) Interfacial condensation polymerization
3- Polymer precipitation methods:
a) Solvent extraction/ evaporation
b) Solvent displacement (nanoprecipitation)
c) Salting out

4. 1-Amphiphilic macromolecule cross-linking :
We make w/o emulsion using our polymer "BSA" and oil
Then we make centrifugation to get the polymer "BSA bovine
serum albumin" out of the oil then we add Add cross-linking
agent (chemical cross-linking) or pre-heated oil (heat cross-
linking)

5. 2- Polymerization based methods:
We start with monomer till we get polymer.
a) Emulsion polymerization:
We start with a beaker containing monomer molecules then we
add surfactant with hydrophilic heads and lipophilic tails which
tend to form micelles in water
The monomer added is lipophilic so it tends to
escape from water and enters the lipophilic core of
micelles.
Then we add something called radical initiator
which enters the micelles and force the monomers
To form a polymer via polymerization
process .
Then the micelles dissociate and the
polymer chains are attached to each other
Cautions : experiment is done under
nitrogen atmosphere as O2 enterferes with it.

6. b) dispersion polymerization:
monomer is dissolved in the Aq medium, which act as a
precipitant for formed polymer.
Nucleation is directly induced in Aq Monomer solution. So
STABILIZER/ SURFACTANT is no needed .
Initiation here is achieved by different mechanism, but mostly
it is by irradiating solution with high energy radiation (g, UV,
strong visible light).
c) interfacial complexation :
It involves polymerization of two different monomers,
dissolved in two phases respectively, Continuous and Dispersed
phase as o/w or w/o emulsion.
Polymerization reaction takes place at the interfaces of two
liquids.
Nanometre-sized hollow polymer particles were synthesized
by employing interfacial cross-linking reactions as polyaddition
and polycondensation or radical polymerization using the
radical initiator .
3- Polymer precipitation methods:
a) Solvent extraction method :

7. a).1 single emulsion:
used with lipophilic drugs
here drug and polymer are dissolved in a common organic
solvent and then emulsified to form o/w emulsion
Then we make solvent evaporation to get rid of the organic
solvent in which the polymer and the drug are dissolved within
the oily system dispersed in the aqueous continuous phase.
And then we get the polymer-drug nanoparticle.
a).2 double emulsion:
used with hydrophilic drugs.

8. here the drug is dissolved in an aqueous medium and
emulsified into the oily phase containing polymers and their
solvents to form w/o emulsion
+
Then we emulsify our whole system into an agueous external
phase to form w/o/w emulsion with the addition of "PVA poly
vinyl alcohol" as stabilizer in the aqueous continuous phase
Then we make solvent evaporation step to get rid of the
organic solvent such as dichloromethane.
b) Solvent displacement method:
Its principle is that precipitation
occurs when two different
phases ( Aqueous phase and
organic phase) are added
together under magnetic stirring.
C) salting out :

9. Resourses
 Kumari A, Yadav S, Yadav SC, “Biodegradable polymeric
nanoparticles based drug delivery systems”,Colloids and
Surfaces B: Biointerfaces , elsevier.com, 2010, vol 75 Pg:1–18
 Haggag YA "Preparation of insulin loaded biodegradable
nanoparticles".
 Beck-Broichsitter M1
, Rytting E, Lebhardt T, Wang X, Kissel T "
Preparation of nanoparticles by solvent displacement for drug
delivery"
 Shivam Thakore, Rudree Pathak Ankit Patel ”polymeric
nanoparticles : a novel approach".