Jayabalan M, Shunmugakumar N
Sree Chitra Tirunal Institute for Medical Science and Technology, Polymer Division, Trivandrum, India.
Med Prog Technol. 1994;20(3-4):261-70.
Shelf life and long-term environmental stability of polyurethanes intended for percutaneous applications and various biomedical applications are largely depend on their resistance to fungal attack and growth. Two classes of aliphatic crosslinked polyurethanes based on hexamethylene diisocyanate (HDI) and bicyclo-hexyl-methane diisocyanate (SM DI) were subjected to cell-free enzymatic degradation using hydrolytic and oxidative enzymes and to fungal attack and fungal growth using Aspergillus niger and Penicillium Sp. The present crosslinked polyurethanes are not susceptible to degradation by hydrolytic enzymes. The marginal loss of tensile strength in buffered solution of papain is attributed to plasticization by the absorbed components of the enzyme solution. The PEG based crosslinked polyurethanes are marginally susceptible to degradation by lactic dehydrogenase solution. The present polyurethanes are resistant to fungal attack. The fungal growth was not observed with PTMG and PPG based Polyurethanes, however, a marginal growth was observed with PEG based polyurethanes.
用于经皮应用和各种生物医学应用的聚氨酯的保质期和长期环境稳定性在很大程度上取决于它们对真菌侵袭和生长的抵抗力。基于六亚甲基二异氰酸酯（HDI）和双环 - 己基 - 甲烷二异氰酸酯（SM DI）的两类脂肪族交联聚氨酯，使用水解酶和氧化酶进行无细胞酶降解，并使用黑曲霉和青霉属进行真菌侵袭和真菌生长实验。目前的交联聚氨酯不易被水解酶降解。木瓜蛋白酶缓冲溶液中拉伸强度的轻微损失归因于酶溶液吸收成分的增塑作用。基于聚乙二醇（PEG）的交联聚氨酯对乳酸脱氢酶溶液的降解略微敏感。目前的聚氨酯对真菌侵袭具有抗性。基于聚四氢呋喃（PTMG）和聚丙二醇（PPG）的聚氨酯未观察到真菌生长，然而，基于PEG的聚氨酯观察到轻微生长。
