Use of triethylcitrate plasticizer in the production of poly-L-lactic acid implants with different degradation times

Bioabsorbable materials have been widely used in the repair of damaged tissue as well as in the controlled release of drugs and as a supports for cultured cells. The degradation time of poly-L-(lactic acid) (PLLA) may be controlled by altering the polymer porosity through the addition of the plasticizer triethylcitrate. This in turn influences the extent cellular infiltration. In this study, we examined the degradation of PLLA membranes containing different concentrations of plasticizer. PLLA discs were implanted subcutaneouly in rats and withdrawn 2, 14 and 60 days after implantation. The samples were processed for light microscopy and scanning electron microscopy (SEM). Polymer degradation was proportional to the concentration of plasticizer, indicating that triethylcitrate could affect the degradation time of the implants, without damaging the polymer biocompatibility.