| Environmental hormone widely dispersed in the environment and a small amount of environmental hormones can cause great harm to humans, animals and ecological environment. Developing highly sensitive methods for environmental hormone assay is very important because of their presence at trace levels in the environment. At present, environmental hormones are detected mostly by chromatographic technology. Although these methods possess high sensitivity and excellent selectivity, the instruments used are expensive and sample pretreatments are relatively complicated. As a important analytical method, electrochemical method are often simple, rapid, and less expensive. Acetylene black (AB) possesses large specific surface, good conductivity and strong adsorptive ability. Ionic liquids (ILs) have many advantages such as stability electrochemical properties, wide electrochemical window, excellent conductivity, low toxicity etc. In this paper, several electrochemical sensing platforms were developed for the determination of environmental hormones that is based on the modification of a glassy carbon electrode with acetylene black and ionic liquids. The main results are summarized as follows:(1) An acetylene black-ionic liquids composite film modified electrode was developed for the determination of environmental hormone bisphenol A (BPA). The oxidation peak currents of bisphenol A at resulting electrode increased significantly, compared with those at a bare electrode and acetylene black-silicone oil composite electrode. Thereby a simple, sensitive and direct electrochemical method for the determination of bisphenol A was established. Under optimal conditions, oxidation peak current of bisphenol A was found to be directly proportional to its concentration in the range of 9×10-8 1.8×10-5 mol/L (R=0.9977), and the detection limit is 3.1×10-8 mol/L. This method was applied to the determination of bisphenol A in plastics and the recoveries are between 96.2 % 104.8 %.(2) A novel electrochemical method was developed that is based on the modification of a glassy carbon electrode with acetylene black and ionic liquids. The resulting electrode exhibited excellent electrocatalytic activity towards trifluralin in showing markedly increased redox peak currents. The experimental parameters affecting the response to trifluralin were optimized. Under optimal conditions, a linear response was obtained in the range from 8.0×10-8 to 1.2×10-5 mol/L of trifluralin (R =0.9994). The detection limit is 1.0×10-8 mol/L after open-circuit accumulation for 120 s. The method was successfully applied to determine trifluralin in soil samples with satisfactory results.(3) The electrochemical behaviors of diethylstilbestrol at the acetylene black-ionic liquid composite film modified electrode was studied, the results showed that this modified electrode exhibited remarkable electrocatalytic behaviors for the redox of diethylstilbestrol. Hence, a simple and sensitive electroanalytical method was developed for the determination of diethylstilbestrol. Under optimized conditions, a good linear relationship between reduction peak current of diethylstilbestrol and its concentration was obtained in the range of 8×10-8 1.1×10-5 mol/L (R=0.992), with a limit of detect of 1.3×10-8 mol/L.(4) Acetylene black was dispersed into water in the presence of anionic surfactant sodium dodecyl sulfate (SDS), and then a Nafion/SDS/AB modified electrode was prepared. The electrochemical behavior of diethylstilbestrol at the Nafion/SDS/AB film coated glassy carbon electrode was investigated in detail. The Nafion/SDS/AB film coated electrode exhibits electrocatalytic activity to the electrochemical behavior of diethylstilbestrol. The experimental parameters, which influence the current of diethylstilbestrol, were optimized. Under optimized conditions, the oxidation peak current of diethylstilbestrolthe was found to be linear to its concentration in the range of 1×10-8 1.4×10-5 mol/L (R=0.994), with a limit of detect of 6×10-9 mol/L. This electrochemical sensor was successfully applied to the determination of diethylstilbestrol in real samples.
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