Electrocatalytic oxidation of dopamine based on non-covalent functionalization of manganese tetraphenylporphyrin/reduced graphene oxide nanocomposite.
In the present work, a reduced graphene oxide (RGO) supported manganese tetraphenylporphyrin (Mn-TPP) nanocomposite was electrochemically synthesized and used for the highly selective and sensitive detection of dopamine (DA). The nuclear magnetic resonance, scanning electron microscopy and elemental analysis were confirmed the successful formation of RGO/Mn-TPP nanocomposite. The prepared RGO/Mn-TPP nanocomposite modified electrode exhibited an enhanced electrochemical response to DA with less oxidation potential and enhanced response current. The electrochemical studies revealed that the oxidation of the DA at the composite electrode is a surface controlled process. The cyclic voltammetry, differential pulse voltammetry and amperometry methods were enable to detect DA. The working linear range of the electrode was observed from 0.3 to 188.8 μM, limit of detection was 8 nM and the sensitivity was 2.606 μA μM(-1) cm(-2). Here, the positively charged DA and negatively charged porphyrin modified RGO can accelerate the electrocatalysis of DA via electrostatic attraction, while the negatively charged ascorbic acid (AA) repulsed by the negatively charged electrode surface which supported for good selectivity. The good recovery results obtained for the determination of DA present in DA injection samples and human pathological sample further revealed the good practicality of RGO/Mn-TPP nanocomposite film modified electrode.
['Sakthinathan|Subramanian|S|', 'Lee|Hsin Fang|HF|', 'Chen|Shen-Ming|SM|', 'Tamizhdurai|P|P|']
D002384:Catalysis D004298:Dopamine D055664:Electrochemical Techniques D006108:Graphite D006801:Humans D008665:Metalloporphyrins D053761:Nanocomposites D010084:Oxidation-Reduction D010087:Oxides D010316:Particle Size D013499:Surface Properties
Dopamine Manganese tetraphenylporphyrin Reduced graphene oxide Amperometry Electrocatalysis Electrochemical sensor Electrochemistry