Nano Particles

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4/10/2011 monika sharma 1 NANO PARTICLES Ms. Monika Dr. Nawazish Alam M. Pharmacy,Sem 1 Dept. of Pharmaceutics S.B.S. College of Pharmacy, PATTI.

Slide 2:

In Nanotechnology particle is defined as a small object that behaves as a whole unit terms of its transport and properties. 4/10/2011 monika sharma 2

Introduction to nano particles:

Introduction to nano particles Nanoparticles are Particulate Drug delivery systems with a size range of 10 -1000nm in which the drug may be dispersed,encapsulated or absorbed. Nanoparticles are subdivided into two groups. 1) Nanospheres 2) Nanocapsules Nanospheres are small solid monolithic spheres constituted of a dense solid polymeric network. Nanocapsules are small reservoirs consisting of a central cavity surrounded by a polymeric membrane. 4/10/2011 monika sharma 3

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Background:- In scientific terms Michael Faraday provided first description of optical properties of nanometer scale metals in his classic 1857 paper After him,Turner points out that when thin leaves of gold or silver are mounted upon glass and heated to a temp.which will below a red heat (app.500 c) then change in properties takes place. The result is that white light freely transmitted, reflection is diminshed and electricity resistivity is increased. 4/10/2011 monika sharma 4

Characteristics of nanoparticles :

Characteristics of nanoparticles Particle size Surface properties of nanoparticles Drug-polymer interactions Drug loading In-vitro drug release 4/10/2011 monika sharma 5

Advantages of nanoparticles:

Advantages of nanoparticles Controlled and sustained drug release at the site of action Site specific targetting can be achieved Particle size and surface characteristics of nanoparticles can be easily modified to achieve both passive and active drug targetting Reduced drug toxicity 4/10/2011 monika sharma 6

Disadvantages of nanoparticles:

Disadvantages of nanoparticles Small size and large surface area lead to particle-particle aggregation. Small particle size and large surface area resulted in limited drug loading and burst release. 4/10/2011 monika sharma 7

Preparation of Nanoparticles:

Preparation of Nanoparticles Proteins Polysaccharides Synthetic polymers. SELECTION OF MATRIX MATERIAL Size of nanomaterial . Inherent properties of drug. Surface characteristics. Degree of bio- degradebility,bio -compatibility and toxicity. Drug release profile. Antigenicity of final product. 4/10/2011 monika sharma 8

methods:

methods Emulsion polymerisation Solvent evaporation method Nanoprecipitation Micro encapsulation Salting out 4/10/2011 monika sharma 9

polymerisation:

polymerisation Monomers are polymerised in aq. Solution. Drug incorporated either by dissolving in the polymerisation medium or by adsorption onto nanopaticles after polymerisation completed. Nanoparticle suspension then purified by ultracentrifugation. Re-suspend the particles in an isotonic surfactant free medium. 4/10/2011 monika sharma 10

Nanoprecipitation:

Nanoprecipitation 4/10/2011 monika sharma 11

Salting out:

Salting out 4/10/2011 monika sharma 12

SOLVENT EVAPORATION:

SOLVENT EVAPORATION Polymer dissolved in organic solvent eg.chloroform,dichloromethane,which is used as a solvent for dissolving the hydrophobic drug. Mixture of polymer and drug solution is then emulsified in an aq.solution containing a surfactant or emulsifying agent to form o/w emulsion. After the formation of stable emulsion organic solvent is evaporated either by reducing the pressure or by continuous stirring. To produce small particle size,high speed homogenization or ultrasonification is done. 4/10/2011 monika sharma 13

Coacervation:

Coacervation 4/10/2011 monika sharma 14

Applications :

Applications Tumour targetting using nanoparticles delivery systems. Nanoparticles for oral delivery of peptides and proteins. Targetting of nanoparticles to epithelial cells in the GI tract using ligands . Nanoparticles for gene delivery. Nanoparticles for drug delivery into the brain. 4/10/2011 monika sharma 15

Polymers used in the synthesis of nanoparticles:

Polymers used in the synthesis of nanoparticles Polymer Drug Observation Albumin Piroxicam Increased bioavailability compared to commercial eye drops Albumin Ganciclovir The residence time is prolonged (2 weeks) Chitosan Cyclosporin A Therapeutic concentrations in cornea and conjunctiva during at least 48 hrs Carrageenan gelatin Timolol Higher bioavailability in aqueous humor compared to commercial eye drops and insitu gelling system Eudragit Ibuprofen Improved ocular bioavailability 4/10/2011 monika sharma 16

Freeze drying of nanoparticles:

Freeze drying of nanoparticles Advantages Prevention from degradation and/or solubilization of polymer Prevention from drug leakage,drug desorption,drug degradation Easy to handle and store Readily dispersible in water without modification in their physicochemical properties 4/10/2011 monika sharma 17

Conclusion::

Conclusion: The major objective of clinical therapeutics is to provide and maintain adequate concentration of drugs at the site of action Currently available conventional dosage forms for ophthalmic use induce the absorption of drugs only to the extent of 1-3% Nanoparticles represent a promising drug delivery system of controlled and targetted drug release with less toxicity when compared to other systems and are stable in biological fluids Nanoparticles are readily permeable through the biological membranes, increase the drug residence time. Hence absorption , bioavailability of the drugs is better when compared to conventional ocular drug delivery systems 4/10/2011 monika sharma 18

Slide 19:

Thank you for listening me……… 4/10/2011 monika sharma 19

Questions?:

Questions? 4/10/2011 monika sharma 20