Department of Chemistry, Middle East Technical University, Ankara 06800, Turkey.
Department of Biotechnology, Middle East Technical University, Ankara 06800, Turkey.
Colloids Surf B Biointerfaces. 2013 Nov 1;111:549-55. doi: 10.1016/j.colsurfb.2013.07.013. Epub 2013 Jul 12.
A conducting polymer modified with sepiolite was utilized in the construction of a highly sensitive and fast amperometric cholesterol biosensor. In this study a monomer; (10,13-bis(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)dibenzo[a,c]phenazine (PHED)) was synthesized and then its polymer was coated on a graphite electrode by electropolymerization to obtain a matrix for enzyme immobilization. Cholesterol oxidase was immobilized onto polymer coated electrode by adsorption technique. Sepiolite was introduced for a successful immobilization of the cholesterol oxidase. Immobilized enzyme kinetic parameters (KM(app), Imax) were evaluated by Michaelis-Menten kinetics and calculated as 0.031 mM and 6.06 μA, respectively. LOD and sensitivity were estimated as 0.36 μM and 1.64 mA/mMcm(2). Characterization of designed biosensor was done to examine the effect of various factors such as enzyme amount, optimum pH and shelf-life. A novel accurate and inexpensive cholesterol biosensor was developed for the determination of total cholesterol in food samples.
一种用海泡石改性的导电聚合物被用于构建一种高灵敏度和快速电流型胆固醇生物传感器。在这项研究中，合成了一种单体；（10,13-双（2,3-二氢噻吩[3,4-b][1,4]二恶英-5-基）二苯并[a,c]吩嗪（PHED）），然后通过电化学聚合将其聚合物涂覆在石墨电极上，以获得用于酶固定化的基质。通过吸附技术将胆固醇氧化酶固定在聚合物涂覆的电极上。海泡石被引入以成功固定胆固醇氧化酶。通过米氏动力学评估了固定化酶的动力学参数（KM(app)，Imax），并分别计算为 0.031 mM 和 6.06 μA。LOD 和灵敏度分别估计为 0.36 μM 和 1.64 mA/mMcm(2)。设计的生物传感器的特性被检查以检查各种因素，如酶量、最佳 pH 值和保质期的影响。为了测定食品样品中的总胆固醇，开发了一种新型准确且廉价的胆固醇生物传感器。
