Trace-level determination of amlodipine besylate by immobilization of palladium-silver bi-metallic nanoparticles on reduced graphene oxide as an electrochemical sensor in biological and pharmaceutical samples

Abstract Bi-metallic Pd Ag was homogeneously dispersed on reduced graphene oxide (rGO) nanosheets and was synthesized by reducing ethylene glycol. Pd-Ag/rGO nanocomposite was fabricated on GCE using a drop-casting method for sensing of amlodipine and was characterized using transmission electron microscopy (TEM) and energy-dispersive X-ray analysis (EDX). This nanocomposite exhibited excellent electrooxidative behavior of amlodipine in 0.1 M PBS buffer at pH 6.0. The anodic peak current of amlodipine was observed at a potential of 0.7 V. Moreover, the proposed sensor exhibited superior sensitivity for the detection of AML with a linear range from 0.01 to 0.14 μM with LOD = 0.007 μM. The effectiveness of the proposed Pd-Ag/rGO sensor was tested using the DPV technique for simultaneous detection of amlodipine, paracetamol, and dopamine in both biological and pharmaceutical samples with satisfactory results.