pharmaceutics colloidal system all topic cover in ppt important for pharmacy students

1. Colloidal Dispersion System
Assistant Professor
Miss. Priya P. Mane Deshmukh
College of Pharmacy , Paniv

2. Disperse particles consist of:
Internal Phase/
Dispersed Phase
Dispersed Medium

3. Colloidal system is dispersion where in
internal phase dispersed particles are
distributed uniformly in a dispersion medium
(External/continuous Phase). Particle size-0.5
to 1 micron
 In colloidal systems particles pass through
filter paper but do not pass through semi
permeable membrane diffuse very slowly.
Exemples:-Liposome, Nanoparticles, Paint,
Milk,Radioactive Colloids-198Au,98mTc
Colloidal system

4. Class Particle Size* Characteristics of System Examples
Molecular dispersion Lessthan 1nm Invisible in electron
microscope
Passthrough ultrafilter
and semipermeable
membrane
Undergo rapid diffusion
Oxygen molecules,
ordinary ions, glucose
Colloidal dispersion From 1nm to 0.5 µm Not resolved by ordinary Colloidal silver sols,
microscope (although natural and synthetic
may be detected under polymers, cheese, butter,
ultramicroscope) jelly, paint, milk, shaving
Visible in electron cream, etc.
microscope
Passthrough filter paper
Do not pass
semipermeable
membrane
Diffuse very slowly
Coarse dispersion Greater than 0.5µm Visible under microscope Grains of sand, most
Do not pass through pharmaceutical emulsions
normal filter paper and suspensions, red blood
Do not dialyze through cells
semipermeable
membrane
Do not diffuse
* 1 nm (nanometer) = 10-9 m; 1 µm (micrometer) = 10-6 m. CHAPTER 05
Classification of dispersion Colloidal system

5. Coarse Dispersio
(Exp: Fat emulsio
Molecular Dispersion
(Exp:Glucose Solution)
Colloidal Dispersion
(Exp: Gold ColloidalDispersion)

6. Dispersed
Phase
Dispersion
Medium
Colloid Type Examples
Solid Solid Solid sol Pearls, opals
Liquid Solid Solid emulsion Cheese, butter
Gas Solid Solid foam Pumice, marshmallow, sponge
Solid Liquid Sol, gel Jelly, paint, blood
Liquid Liquid Emulsion Milk, mayonnaise
Gas Liquid Foam Whipped cream, shaving cream
Solid Gas Solid aerosol Smoke, dust
Liquid Gas Liquid aerosols Clouds, fog
Gas Gas --- None (A gas in a gasalways
produces a solution)
Classification of Colloidal
I.The original states of their component parts

7. II. Colloidal solutions can be classified in different ways:-
A. Based upon molecular size:-
1.Macromolecular colloids
2. Multi molecular colloids
3. Associated colloids
B. Based upon interaction among phases:-
1. lyophilic colloids
2.lyophobic colloids
3.Amphiphilic colloids

8. Lyophilic (Solvent-loving)
Colloids
Systems containing colloidal
particles that readily interact
with the dispersion medium
Due to their affinity for the
dispersion medium, such
materials can easily form
colloidal dispersions; simply
by dissolving the material in
the solvent being used.
Most lyophilic colloids are
organic molecules, for
example, gelatin, acacia,
insulin, albumin, rubber, and
polystyrene.
Lyophobic (Solvent-hating)
Colloids
Systems composed of materials
that have little attraction, if
any, for the dispersion
medium
It is necessary to use special
methods to prepare
lyophobic colloids.
They are generally composed
of inorganic particles
dispersed in water.
Examples of such materials
are gold, silver, sulfur,
arsenous sulfide, and silver
iodide.
Amphiphilic Colloids
Systems composed of
amphiphiles or surface-active
agents, that are characterized
by having two distinct regions
of opposing solution affinities
within the same molecule or
ion.
When present in a liquid medium
at low concentrations (below
the CMC), the amphiphiles
exist separately and are of
subcolloidal size
As the concentration is increased
(above the CMC), micelles
are formed which may contain
50 or more monomers, the
diameter of each micelle is of
5 nm (colloidal size).
The formation of amphiphilic
colloids is spontaneous, if the
concentration of the
amphiphile exceeds the CMC

9. Colloidal Dispersion Properties
1.Optical Properties
• Farraday Tyndall Effect
• Electron Microscopy
Imaging
• Light ScatteringOptical Properties
2.Kinetic Properties
1. Brownian motion
2. Sedimentation
3. Viscosity
4. Diffusion
3. Electrical Properties
• Electrical double layer
• Electrophoresis
• Electrosmosis
• Donnan membrane effect

10. Optical Properties of Colloidal Dispersion
Turbidity
Tyndall Faraday Effect

11. Brownian Motion
(Kinetic Property of Colloids)
Viscosity η = ηo (1+ 2.5 φ)
Diffusion
Stokes Einstein Equation
Osmotic Pressure
Van Hoff Equation
Sedimentation
Stokes’s Law

12. The Electrical Double Layer

13. Diffusion
Brownian Motion
Osmotic Pressure

14. Sedimentation

17. Application s of colloids
1. Stability
2. Diagnostic agents
3. Toxicity
4. Absorption
5. Targeted drug delivery
6. Therapeutic effects
7. Parenteral