Sensitive and selective electrochemical sensor using silver nanoparticles modified glassy carbon electrode for determination of cholesterol in bovine serum

For the first time, a newly sensitive and simple method for the determination of cholesterol based on coupling of enzymatic assay and electrochemical detection has been developed. Silver nanoparticles modified glassy carbon electrode (AgNPs/GCE) was fabricated by electrochemical deposition technique and used as the working electrode. The electrochemical performances were investigated by cyclic voltammetry and chronoamperometry. Under the optimized conditions, a linear relationship between the reduction current and cholesterol concentration was found in the range of 3.9 mg/dL to 773.4 mg/dL with a detection limit of 0.99 mg/dL. The proposed method was applied to determine cholesterol in bovine serum. The recoveries obtained were within the range of 99.6-100.7%, which indicated that the presented method is applicable to determine cholesterol in bovine serum. In addition this electrochemical sensor displayed very high specificity to cholesterol with no observed interference from easily oxidizable species such as ascorbic acid and uric acid. All these excellent performances of the developed sensor indicated that this sensing platform could be easily extended to the detection of other important biomarkers. (C) 2014 Elsevier B.V. All rights reserved.