New
gentamicin-eluting bioresorbable core/shell fiber structures were developed and studied. These structures were composed of a
polyglyconate core and a porous poly(DL-lactic-co-
glycolic acid) (PDLGA) shell loaded with the
antibiotic agent
gentamicin, prepared using freeze drying of inverted
emulsions. These unique fibers are designed to be used as basic elements of bioresorbable
burn and
ulcer dressings. The investigation focused on the effects of the
emulsion's composition (formulation) on the shell's microstructure, on the drug release profile from the fibers, and on bacterial inhibition. The release profiles generally exhibited an initial burst effect accompanied by a decrease in release rates with time.
Albumin was found to be the most effective
surfactant for stabilizing the inverted
emulsions. All three formulation parameters had a significant effect on
gentamicin's release profile. An increase in the
polymer and organic:aqueous phase ratio or a decrease in the
drug content resulted in a lower burst release and a more moderate release profile. The released
gentamicin also resulted in a significant decrease in bacterial viability and practically no bacteria survived after 2 days when using bacterial concentrations of 1 x 10(7) CFU/mL. Thus, our new fiber structures are effective against the relevant bacterial strains and can be used as basic elements of bioresorbable
drug-eluting
wound dressings.