A nanocomposite based biosensor for cholesterol determination

作者:Karimi Somayeh; Ghourchian Hedayatollah*; Rahimi Parvaneh; Rafiee Pour Hossain Ali
来源:Analytical Methods, 2012, 4(10): 3225-3231.
DOI:10.1039/c2ay25826a

摘要

An electrochemical biosensor was prepared by immobilizing cholesterol oxidase (ChOx) on a nanocomposite consisting of amine functionalized multi-walled carbon nanotubes and a room temperature ionic-liquid (1-butyl-3-methylimidazolium tetrafluoroborate). The biosensor was examined for cholesterol quantification in clinical serum samples. ChOx on the modified electrode exhibited a couple of quasi-reversible redox peaks corresponding to the direct electron transfer of FAD/FADH(2) buried in the enzyme structure. A formal potential of -400 mV was obtained for the immobilized enzyme in phosphate buffer solution (0.1 M, pH 7.4). Under the optimized experimental conditions, the biosensor exhibited a linear response towards cholesterol concentration from 26 nM to 3.4 mu M, with a sensitivity of 540 mu A mM(-1) and a detection limit of 12 nM.

  • 出版日期2012-10