Reusable and mediator-free cholesterol biosensor based on cholesterol oxidase immobilized onto TGA-SAM modified smart bio-chips.

ABSTRACT: A reusable and mediator-free cholesterol biosensor based on cholesterol oxidase (ChOx) was fabricated based on self-assembled monolayer (SAM) of thioglycolic acid (TGA) (covalent enzyme immobilization by dropping method) using bio-chips. Cholesterol was detected with modified bio-chip (Gold/Thioglycolic-acid/Cholesterol-oxidase i.e., Au/TGA/ChOx) by reliable cyclic voltammetric (CV) technique at room conditions. The Au/TGA/ChOx modified bio-chip sensor demonstrates good linearity (1.0 nM to 1.0 mM; R?=?0.9935), low-detection limit (?0.42 nM, SNR?3), and higher sensitivity (?74.3 µA µM(-1) cm(-2)), lowest-small sample volume (50.0 ?L), good stability, and reproducibility. To the best of our knowledge, this is the first statement with a very high sensitivity, low-detection limit, and low-sample volumes are required for cholesterol biosensor using Au/TGA/ChOx-chips assembly. The result of this facile approach was investigated for the biomedical applications for real samples at room conditions with significant assembly (Au/TGA/ChOx) towards the development of selected cholesterol biosensors, which can offer analytical access to a large group of enzymes for wide range of biomedical applications in health-care fields.

SUBMITTER: Rahman MM 

PROVIDER: S-EPMC4065056 | biostudies-literature | 2014

REPOSITORIES: biostudies-literature