Nanocomposites of nitrogen-doped graphene decorated with a palladium silver bimetallic alloy for use as a biosensor for methotrexate detection

摘要: The synthesis and application of composites N-graphene decorated with a bimetallic palladium–silver alloy (PdAg/NG–GCE) for the detection methotrexate (MTX) are described. nanocomposites were synthesized different ratios Ag Pd (3 : 1, 1 : 1 2 : 1). Energy dispersive X-ray spectroscopy (EDS) diffraction (XRD) show that cations completely reduced to Ag, respectively, during formation PdAg/NG. Transmission electron microscopy (TEM) showed good loading between PdAg nanoparticles NG nanosheets Pd : Ag ratio 1 : 1. TEM results also depicted existence sizes 3 13 nm, on surface nanosheets. Electrochemical impedance (EIS) data decrease in charge transfer resistance Pd1Ag1/NG–GCE compared Pd/NG, Ag/NG, GCE, which suggests electron-transfer kinetics MTX oxidation is highly facilitated at Pd1Ag1/NG interface. electrocatalytic activity towards was explored using cyclic voltammetry (CV) differential pulse (DPV) pH 5.8. anodic peak currents approximately 8-fold higher than non-modified electrodes. A linear concentrations over range 0.02–200 μM limit 1.32 nM achieved.