合成ポリアミノ酸繊維の吸収性医用材料としての評価

第1報　ポリーL-グルタミン酸繊維

抄録

Biodegradation behaviors of poly (L-glutamic acid) fibers were performed in vitro and in vivo, including biodegradation and mechanical properties to simulate in vivo fiber degradation, as well as biocompatibility behavior.
Unoriented and oriented poly (L-glutamic acid) (PLGA) fibers were spun from concentrated aqueous poly(L-sodium glutamate) solution. The conformational characterization was performed by wide-angle X-ray diffraction measurement. Copoly (L-glutamic acid/γ-methyl-L-glutamate) fibers were also prepared by saponification reaction of the side chains of poly(γ-methyl-L-glutamate) by sodium hydroxide in EtOH-water mixture. PLGA fibers were found to be extensively degraded by pepsin in a buffer solution at pH=1.6 and 37.0°C. It was pointed out that the unoriented PLGA fiber (α and β) digested faster than the oriented PLGA fiber (β), and that the rate of degradation of copolymer fibers by pronase E (pH=7.4) was extensively depressed by the γ-methyl-L-glutamate side chain.
Next, the enzymatic degradation of these fibers was processed on the surface of the fibers, and the rate of degradation of this case was analyzed by the first order reaction rate concerning the effective surface area of the fiber. This fact was also demonstrated from the direct observation by scanning electron microscopy. The behavior of the decrease in tensile strength as a function of the decrease in fiber weight was different from that of the non-enzymatic degradable fibers such as polyglycolic acid.
The tissue reactions were observed to be extremely slight, and these fiber samples have been replaced by the connective tissue safely during the absorption process.