固定化植物酯酶-显色剂传感膜的制备与性能

Preparation and Properties of the Sensing Membranes Immobilizing Plant Esterase-Chromogenic Agent

采用聚乙烯醇(PVA)与四乙氧基硅烷(TEOS)通过原位溶胶-凝胶法制备了PVA/SiO2有机/无机杂化溶胶,并将显色剂和植物酯酶分散于溶胶中,干燥成膜,得到一类透明度高、亲水-亲丙酮性可调、贮存性好的传感膜.该传感膜在乙酸-α-萘酯溶液中,会于可见光520 nm处出现一个新的吸收峰.传感膜在制备后的12天内活性明显下降,之后基本保持稳定,并且冷藏活性下降率要比室温保存的小很多.但不论是冷藏还是在室温下保存,被固定在杂化膜中的酶活稳定性都比在溶液状态下的明显提高.

PVA/SiO2 organic-inorganic hybrid sol was prepared by means of in-situ sol-gel method, with poly（vinyl alcohol） （PVA） and tetraethylorthosilicate （TEOS） as the materials. Then, the sol with the dispersion of chromo- genic agent and plant esterase was dried to form a kind of transparent sensing membrane with controllable hydrophilicity-acetonephilicity and good storability. It is shown that, （1） when the membrane is soaked in α-naphthyl acetate solution, an absorption band occurs at 520 nm in the ultraviolet-visible spectrum; （2） the enzyme activity of the sensing membrane obviously decreases in 12 days until it reaches a constant value; （3） the decreasing rate of enzyme activity of the sensing membrane in cold storage is significantly smaller than that in room temperature storage; and （4） the stability of the enzyme immobilized in the hybrid membrane is greatly improved, as compared with that of the enzyme in solution.