ABSTRACT
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%.
Subject(s)
Carbon/chemistry , Electrochemical Techniques/methods , Gold/chemistry , Metal Nanoparticles/chemistry , Serotonin/analysis , Cysteine/chemistry , Electrodes , Humans , Oxidation-Reduction , Serotonin/bloodABSTRACT
A new antibiotic, S632A3, was isolated from a cultured broth of Streptomyces hygroscopicus S632. It was purified by column chromatography on silica gel, Sephadex LH-20 and HPLC. Structural studies by analysis of 1H NMR and 13C NMR, MS, UV and IR spectra in comparison with those of S632A2 clarified that S632A3 is an isomer of 9-methylstreptimidone. In addition, this antibiotic showed potent biological activity including differentiation induction effects on HL-60 cell and antitumour activity in vivo.
