聚己内酯在体内的降解、吸收和排泄

The in Vivo Degradation, Adsorption and Excretion of Poly(ε caprolactone)

研究了聚己内酯 (PCL )在大鼠体内的降解 ,结果表明起始分子量 6 .6万的聚己内酯胶囊在体内可完整存在两年 ,两年中分子量逐渐下降 ,两年后降解为低分子量。用氚标记低分子量聚己内酯植入大鼠皮下 ,测定其吸收和排泄 ,结果表明植入 15 d后在血中开始测出放射性 ,同时在粪尿中开始出现放射性排出物。16 5 d后血中放射性基本消失 ,从粪尿中累积排出给入量的 92 % ,植入后 6 0 d及 16 5 d各脏器中放射性分布全部接近本底水平。证明该材料不在体内积蓄 。

The in vivo degradation of poly(ε caprolactone(PCL) was studied in rats. The results showed that the PCL capsules with an initial molecualr weight of 66,000 stayed intact in vivo for 2 years, although the molecular weight of the capsules gradually declined during the two year implantation. It then degraded into low molecular wight pieces with the extension of the implantation. Tritium labeled low molecular weight PCL was subcutaneously implanted in rats to further investigate the absorption and excretion of the material. The radioactivity was first detected in blood 15 days post the implantation. At the same time radioactive excreta were recovered from feces and urine. An accumulative 92% of the implanted radioactive dosage was excreted from feces and urine 135 days post the implantation. In the meanwhile, the blood radioactivity dropped to the background level. Radioactivity in the organs was all close to the background level indicating that the material did not cumulate in body tissue and could be completely excreted.