In vitro study on a degradable poly-L-lactic acid biliary-enteric composite stent / 中国组织工程研究

ABSTRACT

BACKGROUND:The degradable poly-L-lactic acid (PLLA) biliary-enteric composite stent has been developed. OBJECTIVE:To analyze the solubility and biocompatibility of the degradable PLLA biliary-enteric composite stent. METHODS:Solubility:the PLLA composite stent was implanted into artificial gastric acid to detect the dissolution rate within 12 weeks. Pyrogen test:the PLLA composite stent extracts were injected into the rabbits via ear vein to detect the changes of body temperature. Hemolysis test:the PLLA composite stent extracts, normal saline and distil ed water were added into the rabbit anticoagulant, respectively, to detect the hemolysis ratio. Cytocompatibility test:Caco-2 cel s were respectively cultured in the DMEM medium containing 10%fetal bovine serum, rubber material extracts and the PLLA composite stent extracts, and the cel proliferation was detected at 12, 24, 36 and 48 hours;the lactic dehydrogenase release was detected at 2 days. RESULTS AND CONCLUSION:The PLLA composite stent showed a long stability in vivo, and approximately 80%was dissolved at about 20 weeks. No reactions of pyrogen and henolysis were observed in the pyrogen and hemolysis tests. The PLLA composite stent made no effects on the Caco-2 cel proliferation and lactic dehydrogenase release. In conclusion, the PLLA composite material holds a good solubility and cytocompatibility.