Department of Biotechnology, National Institute of Technology Raipur, Raipur, Chhattisgarh, 492010, India.
Appl Biochem Biotechnol. 2020 Jul;191(3):1247-1257. doi: 10.1007/s12010-020-03257-2. Epub 2020 Feb 21.
The work focus on the development of a simple and efficient method of enzyme immobilization over a polystyrene surface using cysteine functionalized copper nanoparticle as linker molecule. The polystyrene surface is activated by generating -NO groups by the process of nitration reaction. The nitrated polystyrene plate then is silanized with (3-mercaptopropyl) trimethoxysilane (MPTS) followed with the coupling of cysteine-capped copper nanoparticles on the silanized surface through thiol moiety. A nanoparticle layer is thus created over the polystyrene surface which is efficiently used for covalent immobilization of urease via an amino group of cysteine through glutaraldehyde treatment. The technique resulted in an enhancement in the enzymatic activity by 72.37% over the soluble counterpart. The immobilized enzyme also exhibited appreciable reusability of about 10 times with activity retention of 82% of its initial activity. Immobilization also offered an increased thermal and pH stability to the immobilized enzyme over the soluble enzyme.
这项工作的重点是开发一种简单有效的酶固定化方法，即在聚苯乙烯表面使用半胱氨酸功能化的铜纳米粒子作为连接分子。聚苯乙烯表面通过硝化反应生成 -NO 基团而被激活。然后，用（3-巯丙基）三甲氧基硅烷（MPTS）对硝化聚苯乙烯板进行硅烷化，随后通过巯基将半胱氨酸封端的铜纳米粒子偶联到硅烷化表面上。在聚苯乙烯表面上形成了一层纳米粒子层，通过戊二醛处理，通过半胱氨酸的氨基将脲酶有效地固定在其上。该技术使酶的活性相对于可溶性酶提高了 72.37%。固定化酶也具有约 10 倍的可重复使用性，其初始活性的保留率为 82%。与可溶性酶相比，固定化酶还提供了更高的热稳定性和 pH 稳定性。
