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Author Jameela, S. R. ♦ Misra, Amit ♦ Jayakrishnan, A.
Source Sree Chitra Tirunal Institute for Medical Sciences & Technology
Content type Text
Publisher Journal of Biomaterials Science-polymer Edition
File Format PDF
Language English
Subject Domain (in DDC) Technology ♦ Medicine & health ♦ Pharmacology and therapeutics
Subject Domain (in MeSH) Macromolecular Substances ♦ Carbohydrates ♦ Chemicals and Drugs ♦ Therapeutics ♦ Analytical, Diagnostic and Therapeutic Techniques and Equipment
Subject Keyword Drug Delivery
Abstract Bovine serum albumin (BSA) and diphtheria toroid (DT) were loaded by passive absorption from aqueous solutions into preformed glutaraldehyde cross-linked chitosan microspheres. In vitro release of BSA under sink conditions at 37 degrees C showed that even though there was a large burst effect, there was a more or less steady increase with time thereafter for several days. Coating the BSA-loaded particles with paraffin oil or with a polymer, such as polylactic acid, modulated drug release. After the initial burst from PLA coated particles, the release rate increased with time for nearly 2 months. Preliminary immunogenicity studies on Wistar rats using DT loaded chitosan spheres showed that the antibody titres were fairly constant over a 5-month period, although very low compared to DT given on alum as control. Histological studies of placebo microspheres intramuscularly injected into rats demonstrated their tissue compatibility. Biodegradation was not complete in 6 months demonstrating the potential of cross-linked chitosan spheres as a long-acting drug delivery vehicle. The study demonstrated the possibility of incorporating biological macromolecules which are very sensitive to organic solvents, pH, temperature, ultrasound, etc. by a passive absorption technique to degradable biopolymer matrices thereby preserving their biological integrity. It is also shown that drugs passively absorbed into such matrices by taking advantage of their swelling behaviour need not necessarily be released completely in the initial 'burst' and a sustained release may be possible for macromolecules thus incorporated.
Education Level UG and PG
Learning Resource Type Article
Educational Framework Medical Council of India (MCI)
Volume Number 6
Issue Number 7
Page Count 12
Starting Page 621
Ending Page 632