Facile synthesis of gold nanoparticles using carbon dots for electrochemical detection of neurotransmitter, dopamine in human serum and as a chemocatalyst for nitroaromatic reduction.

Herein, the authors reported a carbon dots mediated synthesis of gold nanoparticles (AuNPs) at room temperature. Transmission electron microscopy revealed that the AuNPs are spherical in shape with a size of 10 nm. As-prepared AuNPs was immobilised on carbon paste electrode and subjected to electrochemical sensing of an important neurotransmitter dopamine. Differential pulse voltammetry studies revealed sensitive and selective determination of dopamine in the presence of commonly interfering ascorbic acid and uric acid. The linear detection range was 10-600 μM and the limit of detection was 0.7 ± 0.18 μM. The practical application was demonstrated by measuring dopamine in human blood serum and urine samples. The catalytic activity of AuNPs was evaluated by sodium borohydride mediated reduction of nitroaromatic compounds. The reduction kinetics was found to be pseudo-first-order kinetics. All the tested nitroaromatics reduced to corresponding amines in <10 min.