Presence of starch enhancesin vitrobiodegradation and biocompatibility of a gentamicin delivery formulation

The effect of a-amylase degradation on the release of gentamicin from starch-conjugated chitosan microparticles was investigated up to 60 days. Scanning electron micro- scopic observations showed an increase in the porosity and surface roughness of the microparticles as well as reduced diameters. This was confirmed by 67% weight loss of the microparticles in the presence of a-amylase. Over time, a highly porous matrix was obtained leading to increased per- meability and increased water uptake with possible diffusion of gentamicin. Indeed, a faster release of gentamicin was observed with a-amylase. Starch-conjugated chitosan par- ticles are non-toxic and highly biocompatible for an osteo- blast (SaOs-2) and fibroblast (L929) cell line as well as adipose-derived stem cells. When differently produced starch-conjugated chitosan particles were tested, their cyto- toxic effect on SaOs-2 cells was found to be dependent on the crosslinking agent and on the amount of starch used. V C