The Electrochemistry and Determination of Some Neurotransmitters at SrPdO3 Modified Graphite Electrode

Graphite/SrPdO3 was utilized for the sensitive determination of some neurotransmitters, namely dopamine (DA), epinephrine (EP), norepinephrine (NE), serotonin (ST), 3,4-dihydroxyphenylacetic acid (DOPAC) and L-dopa. Graphite/SrPdO3 exhibited higher electrocatalytic activity toward the studied neurotransmitters compared to bare graphite. It was confirmed that graphite electrode was more suitable substrate for immobilization of SrPdO3 perovskite compared to other surfaces. Moreover, simultaneous determinations of L-dopa, ascorbic acid (AA) and uric acid (UA) or ST were achieved with large peak potential separation. The linear response for L-dopa was obtained in the range of 0.6 mu mol L-1 to 9 mu mol L-1 with correlation coefficient 0.996 and detection limit 1.63 nmol L-1. The proposed composite sensor exhibited high reproducibility, enhanced sensitivity, selectivity, anti-interference ability, unique long-term stability (over two months) and applicability in the human urine samples with satisfying results. (C) 2013 The Electrochemical Society. All rights reserved.