Formulation of amorphous carbon embedded CuFeS₂ hybrids for the electrochemical detection of Quercetin

In the present work, amorphous carbon (a-C) embedded polyvinyl pyrrolidine (PVP)-assisted CuFeS₂ (a-C@CuFeS₂-PVP) was synthesized using a facile hydrothermal method to facilitate enhanced electrochemical detection of Quercetin (QR). The formation mechanism of CuFeS₂-PVP was addressed as a function of hydrothermal temperature (120–200 °C). The produced CuFeS₂-PVP and a-C were characterized using XRD (X-ray diffraction), SEM (scanning electron microscopy), TEM (transmission electron microscopy), Raman spectroscopy, and XPS (X-ray photoelectron spectroscopy) techniques. As-synthesized CuFeS₂-PVP and a-C were noticed in terms of micro-flower and layered structures, respectively. The a-C@CuFeS₂-PVP modified glassy carbon electrode (GCE) was employed for the electrochemical detection of QR in Tris-HCl buffer (pH-7.5) by using cyclic voltammetry (CV) and amperometry methods. The a-C@CuFeS₂-PVP modified GCE exhibited enhanced electrocatalytic performance towards QR with a linear detection range of 0.5–250 μM and detection limit of 0.12 μM under optimal conditions. The modified GCE exhibited excellent selectivity, sensitivity (128 μA/mM/cm²), stability, and reproducibility for QR determination. The present study demonstrated the possibility of developing various copper-based chalcogenides with different structures for biosensor applications.