Human flavin-containing monooxygenase 3 (hFMO3), a membrane-bound hepatic protein, belonging to the second most important class of phase-1 drug-metabolizing enzymes, was immobilized in its active form on graphene oxide (GO) for enhanced electrochemical response. To improve protein stabilization and to ensure the electrocatalytic activity of the immobilized enzyme, didodecyldimethylammonium bromide (DDAB) was used to mimic lipid layers of biological membranes and acted as an interface between GO nanomaterial and the hFMO3 biocomponent. Grazing angle attenuated total reflectance Fourier transform infrared (GATR-FT-IR) experiments confirmed the preservation of the protein secondary structure and fold. Electrochemical characterization of the immobilized enzyme with GO and DDAB on glassy carbon electrodes was carried out by cyclic voltammetry, where several parameters including redox potential, electron transfer rate, and surface coverage were determined. This system’s biotechnological application in drug screening was successfully demonstrated by the N-oxidation of two therapeutic drugs, benzydamine (nonsteroidal anti-inflammatory) and tamoxifen (antiestrogenic widely used in breast cancer therapy and chemoprevention), by the immobilized enzyme.
人黄素单加氧酶 3 (hFMO3) 是一种膜结合肝蛋白,属于第二重要的 1 相药物代谢酶类,以其活性形式固定在氧化
石墨烯 (GO) 上,以增强电
化学响应。为了提高蛋白质稳定性并确保固定化酶的电催化活性,使用
双十二烷基二甲基溴化铵 (
DDAB) 来模拟
生物膜的脂质层,并充当 GO 纳米材料和 hFMO3
生物组分之间的界面。掠射角衰减全反射傅里叶变换红外(GATR-FT-IR)实验证实了蛋白质二级结构和折叠的保存。通过循环伏安法对玻碳电极上的 GO 和
DDAB 固定化酶进行电
化学表征,确定了氧化还原电位、电子转移速率和表面覆盖度等多个参数。该系统在药物筛选中的
生物技术应用通过固定化酶对两种治疗药物苯扎明(非甾体类抗炎药)和
他莫昔芬(广泛用于乳腺癌治疗和
化学预防的抗
雌激素)的 N 氧化而得到成功证明。