Shape-memory polymer based on D,L-poly(lactic acid):Biosecurity and cytocompatibility / 中国组织工程研究

ABSTRACT

BACKGROUND:Previous experiments have prepared shape memory polymer based on D,L-poly(lactic acid). According to domestic technical requirements for biological y evaluating biomaterials and medical equipments, tissue-engineered grafts must be subjected to preclinical experiment for biosecurity and cytocompatibility evaluation. OBJECTIVE:To observe the biosecurity of the shape memory polymer based on D,L-poly(lactic acid). METHODS:(1) Bacterial endotoxin testpolymer extract, endotoxin working standard solution and checking standard water were added into limulus reagent, respectively. (2) Sensitization testPolymer extract+Freund’s complete adjuvant+physiological saline and Freund’s complete adjuvant+physiological saline were injected into the scapula of Kunming mice. After induction by intradermal injection, local induction and excitation, stimulate skin erythema and edema degree were observed in animals. (3) Acute toxicity testKunming mice received intraperitoneal injection of 100%, 50%, 25%polymer leaching solution and physiological saline, respectively. (4) 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay for cel proliferationThe direct method was that human umbilical cord vascular endothelial cel s were inoculated onto the polymer film, lactic acid and glass, respectively;the indirect method was that human umbilical cord vascular endothelial cel s were inoculated into the polymer leaching solution, acrylamide solution and 1640 culture solution. RESULTS AND CONCLUSION:This shape memory polymer based on D,L-poly(lactic acid) is free of bacterial contamination in compliance with the biosecurity standards, and it has no al ergenic and toxicity but has good cytocompatibility.