title: The analysis of estrogenic compounds by flow injection analysis with amperometric detection using a boron-doped diamond electrode.
abstract: We report on the use of flow injection analysis with amperometric detection (FIA-EC) to evaluate the potential of using diamond electrodes for the analysis of three estrogenic compounds: estrone, 17-β-estradiol, and estriol. Amperometric detection was performed using a cathodically pretreated boron-doped diamond electrode that offered low background current, relatively low limits of detection, and good response reproducibility and stability. For all three compounds, response linearity was observed over the concentration range tested, 0.10 to 3.0μmol L(-1), the sensitivity was ca. 10mA L mol(-1), and the minimum concentration detection (S/N≥3) was 0.10μmol L(-1) (~27μg L(-1)). The response variability with multiple injections was ca. 10% (RSD) over 20 injections. For estrone, the oxidation reaction on diamond does not proceed through an adsorbed state like it does on glassy carbon. After an initial current attenuation, the diamond electrode exhibited a stable response (oxidation current) for 3 days of continuous use, indicative of minimal surface contamination or fouling by reaction intermediates and products. The method for estrone was assessed using spiked city tap and local river water. Estrone recoveries in spiked city and river water samples presented standard deviations of less than 10%. In summary, the FIA-EC method with a diamond electrode enables sensitive, reproducible, stable, quick, and inexpensive determination of estrogenic compounds in water samples.
authors.affiliation: Departamento de Química, Universidade Federal de São Carlos, C.P. 676, 13560-970 São Carlos, SP, Brazil; Department of Chemistry, Michigan State University, East Lansing, Michigan 48824-1322, USA.
authors.forename: Ricardo F
authors.initials: RF
authors.lastname: Brocenschi
authors.affiliation: Departamento de Química, Universidade Federal de São Carlos, C.P. 676, 13560-970 São Carlos, SP, Brazil.
authors.forename: Romeu C
authors.initials: RC
authors.lastname: Rocha-Filho
authors.affiliation: Facultad de Química, Departamento de Farmacia, Pontificia Universidad Católica de Chile, C.P. 7820436 Santiago, Chile; Department of Chemistry, Michigan State University, East Lansing, Michigan 48824-1322, USA.
authors.forename: Boris
authors.initials: B
authors.lastname: Duran
authors.affiliation: Department of Chemistry, Michigan State University, East Lansing, Michigan 48824-1322, USA. Electronic address: swain@chemistry.msu.edu.
authors.forename: Greg M
authors.initials: GM
authors.lastname: Swain
mesh_terms: D000327:Adsorption; D001895:Boron / Q000737:chemistry*; D055664:Electrochemical Techniques / Q000295:instrumentation* / Q000379:methods*; D004566:Electrodes; D004958:Estradiol / Q000032:analysis / Q000737:chemistry; D004964:Estriol / Q000032:analysis / Q000737:chemistry; D004967:Estrogens / Q000032:analysis* / Q000737:chemistry; D004970:Estrone / Q000032:analysis / Q000737:chemistry; D017022:Flow Injection Analysis / Q000379:methods; D010084:Oxidation-Reduction; D015203:Reproducibility of Results
chemical_list: D004967:Estrogens; D004970:Estrone; D004958:Estradiol; D004964:Estriol; D001895:Boron
keywords: Diamond electrodes; Electroanalysis of estrogenic compounds; Endocrine disrupting compounds; Water quality