Electrochemical sensor using gold nanoparticles and plasma pretreated graphene based on the complexes of calcium and Troponin C to detect Ca2+ in meat

Abstract

A simple electrochemical sensor was developed to determine the concentration of Ca²⁺ in meat. Graphene was treated with oxygen plasma for 10 s and 30 s comparing with the pristine graphene. Through analyzing morphology and chemical composition, the graphene with the lowest defect density was chosen to mix with bovine serum albumin molecule-functionalized gold nanoparticles. It was interesting that only a few gold nanoparticles were trapped in the graphene with 10 s plasma treatment. Then, under the optimal condition measured, the limit of detection was detected as 3.9 × 10^-8 M with a linear relationship from 5 × 10^-8 to 3 × 10^-4 M. Finally, the proposed electrochemical method was applied to detect Ca²⁺ in the pork sample with stability and reproducibility verified by parallel detections. Thus, the proposed method demonstrates its potential for effectively detecting Ca²⁺ in meat and prominently reduces time consumption on operations and pretreatments.

Keywords: Ca(2+); Gold nanoparticles; Graphene; Plasma oxidation; Troponin C.