Preparation and characterization of poly(d,l-lactide-co-glycolide) microspheres for controlled release of anticancer drugs

Eyövge, Gökçen
Breast cancer is the most frequent type of cancer seen in woman. Chemotherapy is one of the most important treatments for breast cancer. However, systemic toxicity, drug resistance and unstable kinetics of the drug in the blood are serious problems of chemotherapy. The use of biodegradable polymers for controlled release of anticancer drugs has gained popularity in recent years. Controlled release of anticancer drugs from polymeric carriers has some advantages such as improvement in the efficiency of treatment, reduction in systemic toxicity and prevention of the drug resistance that is developed by the cancer cells. In this study, it was aimed to prepare such a controlled release system for anticancer drugs which are used in breast cancer treatment by using biodegradable copolymer poly(D,L-lactide-co-glycolide) and to characterize in terms of morphology, size, drug content and drug release rate. In the first part of this study; empty and drug loaded poly (D,L-lactide-co-glycolide) microspheres were prepared. Two sets of empty poly(D,L-lactide-co-glycolide) microspheres were prepared by solvent evaporation technique with single emulsion (oil/water) to determine the effect of stirring rate on size of microspheres. Increase in stirring rate caused decrease in size of microspheres. Drug loaded poly(D,L-lactide-co-glycolide) microspheres were prepared for controlled release of anticancer drugs which are used in breast cancer treatment namely; 5-fluorouracil, methotrexate and tamoxifen by using solvent evaporation technique either with double emulsion (water/oil/water) or single emulsion (oil/water). In the second part of this study; empty and drug loaded microspheres were characterized. Inverted light microscopy and scanning electron microscopy were used to examine morphology and size of microspheres. Drug content of microspheres and amount of released drug were


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Citation Formats
G. Eyövge, “Preparation and characterization of poly(d,l-lactide-co-glycolide) microspheres for controlled release of anticancer drugs,” M.S. - Master of Science, Middle East Technical University, 2005.