Advanced Drug Delivery Systems

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Microspheres are colloidal particles whose size ranges from 1 to 1000 nm.The drug will be either dispersed or dissolved in the empty particles. The micro particulate drug delivery systems are considered and accepted as a reliable means to deliver the drug to the target site.The major applications include Controlled release peptide formulations, Intracellular Delivery, Drug delivery to tissue, treatment of macrophage associated diseases.

The present presentation is elaborating all necessary data like

Definition- Microspheres.
Rationale for drug encapsulation into micro particles.
Loading of drug
Mechanism of Drug release.
Methods of preparation of microspheres.
Characterization of Microspheres.
Applications.
Recent advances.
Future prospective.

Key words: Microspheres, Methods of preparation, Characterization, Applications

Author: http://www.pharmainfo.net/sush

Guide: http://www.pharmainfo.net/Kishorelibra

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Comments

Averineni Ravi Kumar's picture

what are the applications of microspheres.

Averineni Ravi Kumar

Sush's picture

* Micro spheres have immense potential in controlled release. * Micro spheres are very much used in targeting of drugs to a particular organ or a specific part of the organ. * Micro spheres are also used in the treatment of macrophage associated diseases. * Recent studies on the uptake of micro spheres by payer's patches have opened up the possibility of delivering many vaccines by the oral route. * Control rate of release of core material, by rupture of polymer wall. Ref: (2)S.P. Vyas & R.K. Khar. "Microspheres", Targeted &Controlled Drug Delivery (Novel carrier systems) - 1st Edition 2002, P: 417-425, 441-447, 454.

sushma.k

P.J.Subrahmanyam's picture

If polymer is dissolved in organic solvent and the drug is not soluble in that organic solvent in emulsion solvent evaporation technique which type of particulate system we can expect?
Snhpratap's picture

what is the difference between %drug loading and incorporation effeciency can u please expalin what exactly spray congealing method

pratap n h

Anil kumar appapurapu's picture

how the microspheres help in diseased cell sorting?

anilkumar

Bala Vishnu Priya's picture

What is the general criteria for selection of polymer in phase seperation and coacervation technique?

M.Bala Vishnu Priya

Vishnu Murthy Vummaneni's picture

1)Define spray congealing. 2)What is the correct range of microspheres?( as u specified 2 ranges) 3) which technique suits best for preparation of microspheres..?

Vishnu Murthy Vummaneni

P.J.Subrahmanyam's picture

1. What is use of surfactants in emulsion solvent evaporation technique? 2. What is the importance of the density of the continuous system in the emulsion solvent evaporation technique?
Jithan Aukunuru's picture

What are the various applications of microspheres? Which is the first drug approved into the market for the microspheres? What are the other several drugs containing blockbuster formulations (microspheres) in the market?
P.J.Subrahmanyam's picture

In which case we can get smaller size microspheres in emulsion solvent evaporation technique? 1)300rpm, light liquid paraffin as continuous phase 2)500rpm, heavy liquid paraffin as continuous phase 3)300rpm, heavy liquid paraffin as continuous phase 4)500rpm, light liquid paraffin as continuous phase
P.J.Subrahmanyam's picture

Can we use polymer dispersion in water miscible organic phase where the continuous phase is water in the preparation of microspheres by solvent extraction method?
Pradeep Kumar's picture

How can we control the size of a micro-sphere particle in different preparation techniques? What are the considerations in selecting a polymeric substance & other excipients for a micro sphere?

Pradeep Kumar

Madhu's picture

explain the mechanism of drug release form the microspheres. What are the storage conditions for microspheres?

Madhu

Bhanun Agendla's picture

what are the disadvantages of microspheres prepared by solvent evaporation technique

N.bhanu

Suhaas's picture

1. Why is organic phase removed in the solvent extraction? 2. How is your study useful in genetic customization?

Suhaas

Anusha Gottipati's picture

Are the Particles Stable? Can Tissues That Contain Particles Be Embedded?

G.Anusha

Sudip Kokate's picture

hi.. nice ppts please can u explain why there iz need in advances ? specially in which drug delivery it iz suitaible?
Bhavya's picture

is there any possibility of residual solvents in spray drying process if so how can we detect and eliminate residual solvents

k.bhavya

K.N. Rajini Kanth's picture

Good work sushma What are the incompatibility problems that could be overcome by using microspheres what is interfacial polymerization Is there any microsphere preparations available as immunization products What therapeutic class of drug molecules are normally formulated as microspheres

Rajini Kanth

sowjanya gummalla's picture

Among all the methods which one is best one and why?
sowjanya gummalla

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