High index facets-Ag nanoflower enabled efficient electrochemical detection of lead in blood serum and cosmetics

Owing to its importance in environmental pollution and human toxicity, the development of a simple and selective sensor for heavy metal ions is a continued research interest in cross-disciplinary areas of analytical chemistry. The colorimetric analysis based conventional complexation assay of Pb2+ is a cumbersome procedure for practical applications. Herein, we report a novel electrochemical sensor approach based on a high index facets (HIF)‑silver nanoflower modified glassy carbon electrode (AgNF@GCE) for anodic stripping voltammetric detection of lead ion in a pH 4.5 acetate buffer solution. Physicochemical techniques such as XPS, FESEM, and electrochemical studies with Fe(CN)63 were adopted for the surface characterization of the AgNF@GCE. Unlike the conventional Ag-nanoparticles, this new system provides a highly crystalline and large surface area with HIF's {422} and {111} for sensitive and selective electrochemical analysis of Pb2+ ion. Under an optimal experimental condition, AgNF@GCE showed a linear calibration plot in the range of 10–700 ppb of Pb2+ ion with a detection limit 0.74 ppb. Eight repetitive measurements of 50 ppb Pb2+ yielded a relative standard deviation value of 2.8%. The sensor showed tolerable interference with other metal ions such as Cu2+, Fe2+, Mg2+, Ni2+, K+, and Na+. As practical applicability, selective detection of lead concentration in blood-serum and cosmetics were successfully analyzed with appreciable recovery values.