title: Electrochemical determination of estradiol using a thin film containing reduced graphene oxide and dihexadecylphosphate.
abstract: Graphene is a material that has attracted attention with regard to sensing and biosensing applications in recent years. Here, we report a novel treatment (using ultrasonic bath and ultrasonic tip) to obtain graphene oxide (GO) and a new stable conducting film using reduced graphene oxide (RGO) and dihexadecylphosphate film (DHP). The GO was obtained by chemical exfoliation and it was reduced using NaBH4. Subsequently, RGO-DHP dispersion was prepared and it was dropped onto a glassy carbon electrode by casting technique. The electrode was characterized by cyclic voltammetry and electrochemical spectroscopy impedance. The voltammetric behavior of the RGO-DHP/GC electrode in the presence of estradiol was studied, and the results reported an irreversible oxidation peak current at 0.6V. Under the optimal experimental conditions, using linear sweep adsorptive stripping voltammetry, the detection limit obtained for this hormone was 7.7×10(-8)mol L(-1). The proposed electrode can be attractive for applications as electrochemical sensors and biosensors.
authors.affiliation: Nanomedicine and Nanotoxicology Group, Instituto de Física de São Carlos, Universidade de São Paulo, 13566-390 São Carlos, SP, Brazil. Electronic address: brunocj@ymail.com.
authors.forename: Bruno C
authors.initials: BC
authors.lastname: Janegitz
authors.affiliation: Nanomedicine and Nanotoxicology Group, Instituto de Física de São Carlos, Universidade de São Paulo, 13566-390 São Carlos, SP, Brazil.
authors.forename: Fabrício A
authors.initials: FA
authors.lastname: dos Santos
authors.affiliation: Departamento de Química, Universidade Federal de São Carlos, 13565-970 São Carlos, SP, Brazil.
authors.forename: Ronaldo C
authors.initials: RC
authors.lastname: Faria
authors.affiliation: Nanomedicine and Nanotoxicology Group, Instituto de Física de São Carlos, Universidade de São Paulo, 13566-390 São Carlos, SP, Brazil.
authors.forename: Valtencir
authors.initials: V
authors.lastname: Zucolotto
mesh_terms: D015374:Biosensing Techniques; D002623:Chemistry Techniques, Analytical / Q000379:methods*; D055664:Electrochemical Techniques; D004566:Electrodes; D004958:Estradiol / Q000032:analysis* / Q000652:urine; D006108:Graphite / Q000737:chemistry*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D010755:Organophosphates / Q000737:chemistry*; D010084:Oxidation-Reduction; D010087:Oxides / Q000737:chemistry
chemical_list: D010755:Organophosphates; D010087:Oxides; C002290:dicetylphosphate; D004958:Estradiol; D006108:Graphite
keywords: Dihexadecylphosphate film (DHP); Electrochemical determination; Estradiol determination; Reduced graphene oxide (RGO)