A sepiolite modified conducting polymer based biosensor


Soylemez S., Kanik F. E., Tarkuc S., UDUM Y., TOPPARE L. K.

COLLOIDS AND SURFACES B-BIOINTERFACES, cilt.111, ss.549-555, 2013 (SCI-Expanded) identifier identifier identifier

Özet

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 (K-M(app), I-max) were evaluated by Michaelis-Menten kinetics and calculated as 0.031 mM and 6.06 mu A, respectively. LOD and sensitivity were estimated as 0.36 mu M 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. (C) 2013 Elsevier B.V. All rights reserved.