Biodegradable Polymeric Microparticles in Biomedical Applications

A wide range of polymeric materials are available for biomedical applications. The number of materials that are approved for human use, however, is small. Much attention has recently been paid to materials used in controlled drug delivery over a prolonged period of time, targeting drugs to specific sites in cancer chemotherapy 1 and intracellular parasitic diseases. 2 If drug delivery devices are resistant to biodegradation, upon repeated treatment they accumulate in the liver of the patient which could eventually result in adverse effects. As a consequence, many hydrophilic addition polymers have been banned from medicinal use. Therefore, the use of biodegradable polymers is required in these systems. 3 Degradable systems have the advantage of obviating the need of surgical removal of the drug-depleted device which can always be the source of infection. 4 Potentially, degradable matrix systems also have a number of other advantages such as simplicity of design and predictability of release, if the release is controlled solely by matrix degradation. 5