Electrochemical graphene nanoribbons for dopamine and serotonin determination

BONETTO M. CELINA; SACCO NATALIA J.; CORTÓN, EDUARDO.

Valparaiso

Congreso; 10th Ibero-American Congress on Sensors IBERSENSOR; 2016

Universidad Técnica Federico Santa María

Electrochemically active neurotransmitters such asdopamine (DO) as well as serotonin (5-HT) can be directly detected byelectrochemical oxidation. These determinations are of great interest foridentification of cognitive dysfunction of neurological diseases such asdepression, epilepsy, Parkinson, senile dementia, or squizofrenia as early aspossible in order to minimize the deleterious effects and production losses by an essentially young disabled patient population [Willner, 1995; Han et al.,2014]. However the redox behavior of these species at bareelectrodes take place at similar potentials than ascorbic acid (AA) and uricacid (UA) which results in rather poor selectivity and reproducibility [Ventonet al., 2002; Robinson et al., 2008].Graphene modified electrodes have been employed toovercome these shortcomings. Graphene is a metal-like conductor, butnanoribbons (GNR) can generally be either metallic or semiconducting dependingon the patterns formed by their edges [Nakada et al., 1996]. Shinde [2011] hasreported an electrochemical approach for transforming MWCNTs into GNRs, underambient conditions, simplifying experimental and waste disposal conditionspresented by the Kosynkin/Tour´s longitudinal unzipping method [Kosynkin etal., 2009].We report here for the firsttime to our knowledge, the simultaneous determination of DO and 5-HT in thepresence of AA and UA using a glassy carbon (GC) electrode modified withreduced GNR (rGNR/GC) obtained from Shinde´s electrochemical treatment ofMWCNT.