Determination of Diethylstilbestrol in Environmental Water Based on Co(II)-Sensitized Electrochemical Sensing

Abstract

In this research, a simple electrochemical sensor (c-MWCNTs/Nafion/GCE) was prepared by carboxylated multi-walled carbon nanotube, perfluorosulfonic acid polymer and glassy carbon electrode using drop coating method, and based on the obvious sensitization effect on the redox peak current of diethylstilbestrol (DES) in the presence of Co2+, a new electrochemical sensing method for the determination of DES in water was established. In a buffered solution of 0.2 mol l−1 NaH2PO4-Na2HPO4 at pH = 7.0, differential pulse voltammetry (DPV) was used when the Co2+ concentration was 20 μmol l−1. Under the optimized conditions of −0.2 ∼ −0.4 V (vs SCE), −0.2 V enrichment potential, and 120 s enrichment time, the concentration of DES showed a good linear relationship with the peak current over the range of 0.3 to 90 μmol l−1, and the detection limit(S/N = 3) was 0.01 μmol l−1. The actual water sample was detected, and the recovery was between 89.17% and 101.23%. This method had the characteristics of simple operation, low analysis cost and fast analysis speed, and had the potential application value of detecting DES in environmental water.

Determination of diethylstilbestrol in environmental water based on electrochemical senser modified with vanadium based metal organic framework material composite

“…The GCE was polished to a mirror-like finish used 0.05 μm α-Al 2 O 3 polished powder on a moistened suede cloth, ultrasonic cleaned 3 min in anhydrous ethanol and ultrapure water, separately. Follow the experimental steps of the literature [27], CV was performed on the electrodes in the potential range of −0.3 ∼ 1.0 V and −0.2 ∼ 0.6 V until stable and meet the test requirements.…”

“…So far, several methods have been reported for the determination of DES, including gas chromatography and its hyphenated techniques [9][10][11], liquid chromatography and its hyphenated techniques [12][13][14], immunoassay methods [15][16][17], microbiological methods [18][19][20], spectroscopic methods [21][22][23] , electrochemical methods [24][25][26][27] and so forth. High performance liquid chromatography (HPLC) and its coupled techniques have the advantages of high separation capacity, wide applicability and high sensitivity, but they require complex instrumentation and professional operation, and some samples need to be pre-treated, which increases the complexity and time cost of analysis.…”

“…Bi 2 WO 6 nanosheets have high redox capacity, unique two-dimensional lamellar structure with large specific surface area and abundant surface active sites, and better chemical and thermal stability, but the method of preparing Bi 2 WO 6 nanosheets was more complicated and time-consuming, the uniformity of carbon paste electrode material is uncertain, resulting in measurement errors due to differences in the cross-sections used each time. Zeng et al [27] proposed a convenient method for detecting DES based on the complexation effect of Co 2+ and DES, the detection limit was 0.01 μM. The method was highly novel and has a low detection limit, but the binding of Co 2+ and DES was not guaranteed to be complete, which affects the stability of the method.…”