AMPHIPHILIC BLOCK COPOLYMER-LIPASE AGGREGATE IN AQUEOUS-ORGANIC MEDIA

Light-scattering analysis indicated that the polymer aggregate of an a mphiphilic block copolymer (Ib) consisting of poly[(N-nonanoylimino)et hylene] and poly[(N-acetylimino)ethylene] in aqueous solution maintain ed its structure even at the addition of 80% methanol, whereas an aggr egate structure of an amphiphilic block copolymer (la) consisting of p oly[(N-pentanoylimino)ethylene] and poly[(N-acetyliminio)ethylene] in aqueous solution was disrupted by the addition of 40% methanol. The po lymer aggregate of Ib also maintained its structure even with the addi tion of 60% acetonitrile. Lipase P was largely incorporated into the a ggregate of Ib in aqueous solution. Without the polymer aggregate of I b, activity was significantly decreased at the addition of 30% acetoni trile. However, in the presence of the polymer aggregate, more than 40 % activity still remained even at an acetonitrile content of 30%.