title: One-step electrochemical detection of cholesterol in the presence of suitable K₃Fe(CN)₆/phosphate buffer mediator by an electrochemical approach.
abstract: One-step approach of cholesterol biosensor was fabricated onto smart micro-chips based on cholesterol oxidase (ChOx) co-immobilized thioglycolic acid self-assembled monolayer (TGA-SAM) for biomedical applications. The selective cholesterol biosensor was investigated with modified tiny micro-chip (Au/SAM/ChOx) by the facile and reliable cyclic voltammetric (CV) method in a K3Fe(CN)6/phosphate buffer (PB) system. The modified micro-chip displayed a large dynamic range (1.0 nmol L(-1) to 1.0 mmol L(-1)), lower detection limit (~0.49 nmol L(-1), based on S/N~3), higher sensitivity (~93.75 µA µmol L(-2) cm(-2)), good linearity (correlation coefficient r(2), 0.9995), lower sample volume (<50.0 μL), and good stability as well as reproducibility. The Au/TGA system was implemented for a facile and simple approach to the immobilization of ChOx onto micro-chip, which can offer analytical access to a large group of enzymes for a wide range of bio-molecule applications in health-care and biomedical fields. This integrated microchip provides a promising low-cost platform for the sensitive and rapid detection of biomolecules using miniatured samples.
authors.affiliation: Center of Excellence for Advanced Materials Research (CEAMR), Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah 21589, Saudi Arabia; Chemistry Department, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah 21589, Saudi Arabia. Electronic address: mmrahman@kau.edu.sa.
authors.forename: Mohammed M
authors.initials: MM
authors.lastname: Rahman
authors.affiliation: Center of Excellence for Advanced Materials Research (CEAMR), Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah 21589, Saudi Arabia; Chemistry Department, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah 21589, Saudi Arabia.
authors.forename: Abdullah M
authors.initials: AM
authors.lastname: Asiri
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation; D002784:Cholesterol / Q000032:analysis* / Q000378:metabolism; D002789:Cholesterol Oxidase / Q000378:metabolism*; D055664:Electrochemical Techniques / Q000295:instrumentation*; D004800:Enzymes, Immobilized / Q000378:metabolism; D004867:Equipment Design; D005292:Ferricyanides / Q000737:chemistry*; D056656:Lab-On-A-Chip Devices; D057230:Limit of Detection; D010710:Phosphates / Q000737:chemistry; D015203:Reproducibility of Results
chemical_list: D004800:Enzymes, Immobilized; D005292:Ferricyanides; D010710:Phosphates; D002784:Cholesterol; D002789:Cholesterol Oxidase; C028033:potassium ferricyanide
keywords: Cholesterol biosensor; Cholesterol oxidase; Cyclic voltammetry; Micro-chips; Sensitivity; TGA SAM