Electrochemical Investigation Of Chiral Alanine And Arsenate Ion Transfer Across The Liquid/Liquid Interface

Liquid/liquid interface is considered to be the simplest model of biological membrane，and has been paid the close attention by more and more researchers. At present, the iontransfer across Liquid/liquid interface is one of the hotspots in the field of electrochemistryand electroanalytical chemistry. It has close relationships with many important aspects, suchas physiological processes, the distribution of materials between the two phases,environmental analysis, drug release and absorption. While the reasonable interfacialdynamics theory is combined with modern more advanced electrochemical analysis method,the experimental results obtained and application have already reflected that this research inthis field has obtained significant development. It is greatly important for us to understandand master many important physiological processes, to reveal organisms of matter and energymetabolism, to explore the generation of free radicals in life and eliminate its pathogenesis.As is well-known, the substance that the organism needs are mostly organics and thesesubstances are mostly chiral, so chiral separation and detection is especially important. Thedrug release，life process and the interaction of chiral ions became the focus of research. Inindustry generally people choose chiral chromatography method to process on chiralseparation and testing. Therefore, we should be looking for more simple methods to promotethe research. In the past few years, few reports studied the transfer of chiral ion across theliquid/liquid interface. It is believed that if we master the detection mechanism of chiral iontransfer and its enantiomer ion, we will have more deep understanding about life phenomenon.In addition, the content of arsenic compounds dissolved in the landwater is usually below10ng/mL, which often exist in two forms of arsenic （Ⅲ） and arsenic （Ⅴ）. These compounds aretoxic, but the arsenic （Ⅲ） compounds are more toxic than arsenic （Ⅴ） compounds. Today theenvironment is increasingly bad, the investigation on mechanism as well as quantitativeanalysis are both beneficial for the advancement of environmental analysis and environmentaltoxicology assessment.In this paper FT/IFT-SWV was combined with EPPG three-phase electrodes to studychiral Alanine and arsenite ion transfer across the liquid/liquid interface for the first time and the main results obtained were as follows:First, combining three-phase electrode with Fourier Transformed large amplitude squarewave voltammetry, we explored the mechanism and process of chiral Alanine ion transferacross water/chiral solvent interface. The pros and cons of three-phase junction formeddifferent experimental arrangement in the process of ion transfer was analysized in thisresearch. The methode of Fourier Transformed large amplitude square wave voltammetrywhich can quickly measured out dynamics and thermodynamics parameters of ion transfer, isa powerful means of ion transfer research as modeling of biological membrane.Second, the cyclic voltammetry combined with EPPG three-phase electrode for the firsttime was used to study the principle of arsenite （Ⅲ） iontransfer from the aqueous phase tonitrobenzene phase and simultaneously determine both thermodynamics and kinetics of thearsenite （Ⅲ） ion transferacross liquid/liquid interface; Also, thermodynamics and kinetics ofthe arsenite （Ⅲ） ion transfer across liquid/liquid interface obtained by the methods of SWVwere compared with the date obtained by FT-SWV.Third, the transfer behavior and the detection ofAsO₄^3-ion across liquid/liquid interfacewere studied by means of three-phase electrodes. The results show that when open enrichmenttime is10minutes, the PH of phosphoric acid buffer solution is8, scanning rate is100mV/s,the peak potential ofAsO₄^3-is-0.1V, the relationship between peak current and concentrationof arsenic is good linear from2.5×10^-65.0×10-5mol/L.