Determination of free cholesterol based on a novel flow-injection chemiluminescence method by immobilizing enzyme.
A novel flow injection chemiluminescence method is proposed for determination of cholesterol in this paper. The cholesterol oxidase was immobilized onto sol-gel and prepared as an enzymatic reaction column. The determination of cholesterol was performed by quantitative determination of hydrogen peroxide produced from an enzymatic reaction. The luminol-H2O2-metal chelate diperiodatocuprate(III) system ensured that the method was highly sensitive and selective. Free cholesterol was determined over the range 5.0 x 10(-8) mol/L-5.0 x 10(-7) mol/L, with a limit of detection (3sigma) of 1.9 x 10(-8) mol/L. The relative standard deviation (RSD) for 2.5 x 10(-7) mol/L was 2.7% (n = 7). The proposed method offered the advantages of sensitivity, selectivity, simplicity and rapidity for free cholesterol determination, and was successfully applied to the direct determination of free cholesterol in serum.
Hu
Yufei
Y
Department of Chemistry, Institute of Analytical Science, Southwest University, Beibei, Chongqing 400715, People's Republic of China.
Zhang
Zhujun
Z
D002784:Cholesterol / Q000032:analysis*; D002789:Cholesterol Oxidase; D004800:Enzymes, Immobilized; D017022:Flow Injection Analysis / Q000379:methods; D006861:Hydrogen Peroxide / Q000032:analysis; D008163:Luminescent Measurements / Q000379:methods* / Q000592:standards; D008165:Luminol
D004800:Enzymes, Immobilized; D008165:Luminol; D002784:Cholesterol; D006861:Hydrogen Peroxide; D002789:Cholesterol Oxidase