含核酸碱基混合脂质体的制备与膜内分子识别

在生物体系DNA中，碱基对间互补形成的基于氢键的分子识别是生命体系的重要特征，近年来，一些含核酸碱基的化合物在非竞争性介质中，也能进行分子选择性识别，一般来说，单体核酸苷在水溶液中不能通过氢键彼此键合，这主要是因为环境水的竞争性使核酸的碱基对间几乎不可能形成氢键，

Preparation of Phosphatidylcholine/Cationic Amphiphilic Coliposomes and Molecular Recognition in the Bilayer Membranes

An amphiphile, 9-octanyl adenine trimethylammonium bromide(OATMAB amphiphile 3), was synthesized as the receptor. The coliposomes were prepared from phosphatidylcholine and 9-octyl adenine trimethylammonium bromide by sonication of CHCl3-cast films of amphiphiles mixtures [n(PC): n(MOATMAB)=10:1] in doubly distilled water with a bath-type sonicator at 80 W for 3 h. As thymine was added into PC/MAOTMAB coliposomal solution, the absorbability of thymine at 263 nm decreased slowly with time change from 0 to 72 h. The UV-Vis spectroscopic behavior of the thymine in PC/OATMAB/thymine coliposomes(molar ratio=10:1:1) was slowly decreaced with the increase of time. The onset of a hypochromic effect can be ascribed to adenine-thymine interaction. The absorption band levels off at 45.4% of its initial value and stabilizes after several weeks.