含双酚酸链节聚芳醚砜对过氧化氢酶的固定化

Immobilization of catalase by poly(arylene ether sulfone)with bisphenolic acid linkage

聚芳醚砜用聚乙烯吡咯烷酮改性后作为载体,将过氧化氢酶固定在该载体上,研究了固定化酶与游离酶的活性。结果表明,制备的固定化过氧化氢酶吸附率最高可达98.11%,酶活回收率最高可达52.05%。固定化酶的热稳定性和酸碱稳定性显著提高,在55℃保存120 min后仍能保持90%以上活力,而游离酶则只有不到20%的酶活力。固定化酶在pH 5.0和pH 9.0条件下保持5 h仍能保持80%以上酶活力,而游离酶的酶活力均低于40%。固定化酶还表现出良好的操作稳定性,在35℃连续反应20次后相对酶活力为50%,用此载体再次固定化酶后,仍可在连续反应20次后保持50%的相对酶活力。聚芳醚砜可作为固定化过氧化氢酶的优良载体,并有望用于其他酶的固定。

Poly(arylene ether sulfone)was firstly modified by polyvinylpyrrolidone(PVP),which was then employed as a carrier to immobilize the catalase.The activities of immobilized and free catalase were evaluated.The results showed that the adsorption rate of immobilized catalase could reach 98.11%,and the highest recovery rate of catalase was up to 52.05%.The thermal stability and acidic-alkali stability of the immobilized catalase was significantly improved.Their activity was still over 90%after being stored for 120 min at 55℃,while that of the free catalase was less than 20%.After being kept for 5 h with pH 5.0 and 9.0,the activity of the immobilized catalase was still higher than 80%,while that of the free catalase was lower than 40%.The immobilized catalase also showed good operation stability,and the relative enzyme activity was up to 50%after continuous reaction at 35℃for 20 times.After immobilizing the catalase onto the used carrier,the relative catalase activity was up to 50%after continuous reaction for 20 times.The poly(arylene ether sulfone)was an excellent carrier to immobilize catalase and was expected to be used for immobilizing other enzymes.