The separation on microchip provides the advantages including high efficiency, increased throughput, reduced quantities of hazardous materials, cost saving, relatively facile instrumentation, improved portability, etc. A technique of micellar electrokinetic chromatography (MEKC) coupled with amperometric detection has been actualized on a polydimethylsiloxane microchip for the rapid separation and determination of three phenolic xenoestrogens as octylphenol (OP), 4-nonylphenol (4-NP), and bisphenol A (BPA). The baseline separation of these phenolic xenoestrogens is successfully obtained within 55 s under the optimized MEKC conditions with borate running buffer of pH 8.0 containing sodium dodecyl sulfate and β-cyclodextrin. The linear range for OP, 4-NP, and BPA are 20–1,000, 15–1,000, and 20–1,000 μg/L with the detection limit of 5.0, 4.0, and 3.0 μg/L, respectively. The present method is successfully applied for the determination of these phenolic xenoestrogens in some industrial wastewater samples from mainland of China with the recoveries ranged from 90.2 to 109.4%.

A microemulsion enhanced electrochemiluminescence (ECL) of luminol-H2O2 was studied with the flow-injection (FI) technique. The results revealed that the microemulsion composed with cetyltrimethylammonium bromide (CTAB), n-butanol, n-heptane and water greatly enhanced the ECL especially in acidic medium. The ECL emission increased for 20 to 2 times in this microemulsion medium over the pH range of 5.0–8.0 compared to that in aqueous solution. The mechanism of enhancement of surfactant and microemulsion for luminol-H2O2 ECL was discussed. It is mainly based on the electrostatic interaction between luminol anion and the head group of surfactant, which causes the adsorption and promotes the dissociation of luminol on the surfaces of the microemulsion droplets, favors the oxidation of luminol by the yielded reactive oxygen species (ROSs) during electrolysis. This research is very significant for ECL applications because of the extended practicable pH range which was suitable for environmental and biological systems. As an example, this FI-ECL technique can be applied for determination of oligo proanthocyanidin (OPC) because of its antioxidant property and to evaluate the total antioxidant activity of the grape skin using OPC as an index.

With TiO2 nanoparticles as carrier, a supported nano-material of Au atomic cluster/TiO2 nano-hybrid was synthesized. It was then modified onto the surface of indium tin oxide (ITO) by Nafion to act as a working electrode for exciting the electrochemiluminescence (ECL) of luminol. The properties of the nano-hybrid and the modified electrode were characterized by XRD, XPS, electronic microscopy, electrochemistry and spectroscopy. The experimental results demonstrated that the modification of this nano-hybrid onto the ITO electrode efficiently intensified the ECL of luminol. It was also revealed that the ECL intensity of luminol on this modified electrode showed very sensitive responses to oxygen and hydrogen peroxide. The detection limits for dissolved oxygen and hydrogen peroxide were 2 mg L_1 and 5.5 _ 10_12 M, respectively. Besides the discussion of the intensifying mechanism of this nano-hybrid for ECL of luminol, the developed method was also applied for monitoring dissolved oxygen and evaluating the scavenging efficiency of reactive oxygen species of the Ganoderma lucidum spore.

A flow injection analysis (FIA) system with electrochemiluminescent (ECL) detection has been established. Based on a specially designed flow-through ECL cell with a very simple structure, the system possesses rapid response and high sensitivity. With luminol as the ECL reagent, the response of hydrogen peroxide (H2O2) was investigated on the developed FIA-ECL system. After optimizing the experimental conditions, such as the electric parameters, the buffer condition and the flow rate, it was demonstrated that the developed FIA-ECL system works well for quantified assays. Compared with reported works, the present results indicate that the developed FIA-ECL system has the lowest limit of detection (S/N = 3) of 3.0×10−9 mol/L for H2O2, which is equal to the level of chemiluminescence (CL). The developed system was successfully used to monitor the yield of reactive oxygen species (ROSs) in water vapour during the work of an ultrasonic humidifier with H2O2 as index. And the amount of ROSs in some other real samples, including tap water, drinking water and river water was detected with recoveries from 92.0% to 106%.

An electrochemiluminescent (ECL) biosensor based on immobilized uricase has been developed for uric acid detection with luminol as signaler. The uricase has been embedded in polypyrrole (PPy) matrix on platinum electrode during the electropolymerization of pyrrole monomer at potential of 0.80 V versus Ag/AgCl. This ECL-based biosensor responds to uric acid due to yielded hydrogen peroxide during its catalytic oxidization by uricase with potassium ferricyanide acted as an electron receptor to promote the enzymatic reaction. The so-generated hydrogen peroxide enhanced the ECL intensity of luminol. The kinetic parameters of enzymatic reaction as maximum reaction rates (Vmax) and Michaelis–Menten constants (Km) are also evaluated for 1.42 × 10−3 A s−1 and 3.4 × 10−7M in the presence of potassium ferricyanide, which were all greatly improved. The resulting biosensor showed excellent analytical performance for determination of uric acid as more than 50 times sensitivity than a bare electrode. It gives a 75 pM of detection limit and a relative standard deviation of 4.4% for 6.25×10−9M uric acid (n = 6). This ECL-based biosensor has been successfully applied for determination of uric acid in porphyra and kelp samples.

In this paper, a poly(dimethylsiloxane) microchip with amperometric detector was developed for the electrophoretic separation and determination of neurotransmitters. For increasing the separation efficiency, the microchannel is modified by polystyrene sulphonate/polystyrene nano-sphere self-assembly coating. A stable electro-osmotic flow (EOF) and higher separation efficiency are obtained in proposed modified microchannel. Under optimized conditions, dopamine, epinephrine, catechol, and serotonin are acceptably baseline separated in this 3.5 cm length separation channel with the theoretical plate number from 4.6104 to 2.1105 per meter and resolution from 1.29 to 12.5. The practicability of proposed microchip is validated by the recovery test with cerebrospinal fluid as real sample which resulted from 91.7% to 106.5%.VC 2011 American Institute of Physics.

In order to monitor corrosion risk in cover-zone concrete, an integrated tower type sensor (TTS) was developed to obtain the electrochemical parameters such as concrete resistance, macro-cell current and the corrosion potential of built-in electrodes. To obtain valid macro-cell current value, specialized short-circuit acquisition time equal to 30 s has been defined in present cement mortar. The results indicate that the macro-cell current increases and cement mortar resistance decreases meanwhile with the content of chloride ions increase in imported chloride cement mortar. The effective measurement of the macro-cell current and cement mortar resistance allows TTS to be used as a corrosion risk monitoring system in cover-zone concrete.

基于电化学聚合将蛋白A(staphylococcal protein A)与吡咯掺杂后共聚于电极表面的新方法设计传感界面，结合采用微机电系统（micro electro mechanical systems, MEMS)技术制备的两电极系统，开发了一种新型的利用电聚合引入蛋白A进而固定抗体、提高检测性能的安培型免疫微传感器，并应用于沙门氏菌（Salmonella typhimurium, S.typhi）的检测。考察了传感器检测沙门氏菌的响应特性，优化了相关实验条件及参数，并结合扫描电镜(scanning electron microscopy，SEM)图像验证了该抗体固定方法的有效性。实验表明，采用电化学聚合方法固定蛋白A进行敏感膜修饰，操作简便省时(<10 min)、可控性强，试剂用量少(10 μL),能够有效改善抗体固定效果，提高传感器检测性能，适于微型免疫传感器的表面修饰研究。以此设计的安培型免疫微传感器能够检测100 cfu/mL沙门氏菌溶液，具有良好的重复性和特异性。

A Nafion/multi-wall carbon nanotubes (MWNTs) composite film-modified electrode was fabricated and applied for the sensitive and selective determination of caffeine. Multi-wall carbon nanotubes (MWNTs) were easily dispersed homogeneously into methanol by ultrasonication in the presence of 0.1% Nafion. After evaporating the methanol, a Nafion/MWNTs composite film-modified electrode was achieved. Caffeine can be effectively accumulated at Nafion/MWNTs composite film-modified electrode and produce a sensitive anodic peak at around 1330 mV (vs. SCE) in a 0.01 mol L1 H2SO4 medium (pH 2.0). Compared to the bare electrode and Nafion film-modified electrode, the Nafion/MWNTs film-modified electrode can remarkably increase the anodic peak current of caffeine. Under the suitable conditions, the anodic peak current was linear to caffeine concentration in the range of 6.0  1074.0  104 mol L1, and the limit of detection was 2.3  107 mol L1. The Nafion/MWNTs composite film-modified electrode can be renewed by repetitiously cycling in a blank solution for about three cycles. This newly exploited method was successfully used to determine caffeine in beverage samples.

In this paper, the electrochemical behavior of rutin on a gold nanoparticles/ethylenediamine/multi-wall carbon nanotubes modified glassy carbon electrode (AuNPs/en/MWNTs/GCE) was investigated and the electrochemical parameters of rutin were calculated. Rutin effectively accumulated on the AuNPs/en/ MWNTs/GCE and caused a pair of redox peaks at around 487 mV and 432 mV (vs. SCE) in 0.1 M phosphate buffer solution (pH 3.5). Under optimized conditions, the anodic peak current was linear to the rutin concentration in the range of 4.8  108 M9.6  107 M. The regression equation was: ipa = 2.3728Crutin0.1782 (ipa: 105 A, Crutin: lM, r = 0.9973). The detection limit of 3.2  108 M was obtained. The proposed method was successfully used to the determination of rutin content in tablet samples with satisfactory results.

介绍在得到伏安曲线后，在软件图形中测量曲线的峰数据，如峰电位、峰电流、峰面积等。 根据不同的电化学方法及不同的电化学过程控制，有三种测量方法可供选择：半峰法、高斯法、三切线法。

Simultaneous Determination of Thallium and Lead on a Chemically Modified Electrode with Langmuir Blodgett Film of a p-tert-Butylcalix[4]arene Derivative A new voltammetric sensor, Langmuir – Blodgett (LB) film of a p-tert-butylcalix[4]arene derivative modified glassy carbon electrode, was designed and successfully used in simultaneous determination of Tlþ and Pb2þ by square-wave anodic stripping voltammetry. Under the optimum experimental conditions, this newly developed sensor reveal good linear response for Tlþ and Pb2þ in the concentration range of 3108–4106 mol L1 and 2107–2105 mol L1 respectively. The detect limits are 2108 mol L1 for Tlþ and 8108 mol L1 for Pb2þ. Using proposed method, Tlþ and Pb2þ in environment samples were determined with satisfactory results. Keywords: Calixarenes, Langmuir – Blodgett, Thallium, Lead, Square-wave anodic stripping voltammetry

A highly sensitive electrochemical sensor made of a glassy carbon electrode (GCE) coated with a Langmuir–Blodgett film (LB) containing polyaniline (PAn) doped with p-toluenesulfonic acid (PTSA) (LB/PAn-PTSA/GCE) has been used for the detection of trace concentrations of Ag+. UV–vis absorption spectra indicated that the PAn was doped by PTSA. The surface morphology of the PAn LB film was characterized by atomic force microscopy (AFM). The electrochemical properties of this LB/PAn-PTSA/GCE were studied using electrochemical impedance spectroscopy (EIS) and cyclic voltammetry. The LB/PAn- PTSA/GCE was used as a voltammetric sensor for determination of trace Ag+ at pH 5.0 using linear scanning stripping voltammetry. Under the optimal experimental conditions, the stripping current was proportional to the Ag+ concentration over the range from 6.0×10−10 mol L−1 to 1.0×10−6 mol L−1, with a detection limit of 4.0×10−10 mol L−1. The high sensitivity, selectivity, and stability of this LB/PAn- PTSA/GCE also demonstrated its practical utility for simple, rapid and economical determination of Ag+ in water samples.