Selective detection of neurotransmitter serotonin by a gold nanoparticle-modified glassy carbon electrode.

Gold nanoparticles (GNPs) were allowed to self-assemble onto a glassy carbon electrode (GCE) that was prior modified by L-cysteine. The modified electrode was then used as a voltammetric sensor in detecting the neurotransmitter serotonin. The electrode exhibited a linear voltammetric response for serotonin within a concentration range of 6.0 x 10(-8) M to 6 x 10(-6) M, with a detection limit of 2 x 10(-8) M. The detection of serotonin was found to be unaffected by the presence of epinephrine, dopamine, ascorbic acid and folic acid. The electrode was applied to detect serotonin added to human blood serum, with an average recovery value of 104.67%.