Electrochemical Investigation Of Porphyrin Compound At Liquid/Liquid Interface

A liquid/liquid (L/L) interface has been suggested as a simple model for biological membranes. Electrochemical investigation at the interface between two immiscible electrolyte solutions (ITIES) has received intensive study in the last decades. Considerable interest has been emerging and remarkable developments can be seen in the field of charge transfer at liquid-liquid interface. The liquid-liquid interface is the simplest and most promising model for understanding charge transfer processes in biological systems, which include not only ion transport but also electron transport. Electron transfer at the liquid-liquid interface is fundamentally important for understanding the energy conversion and further investigation in simulated biomemrane.The paper applied both thin-layer cyclic voltammetry (TLCV), which was developed by Anson and co-workers in 1998, and scanning electrochemical microscopy (SECM) which was developed by Bard and co-workers in 1989 to investigate the electron transfer in interface and the antioxidant property of ascorbic acid (AA).There are three parts in this paper, main contents are as follows:1. The historical background and the basic principles of L/L interface were reviewed summarily. Specially based on TLCV and SECM measurements, the prospect of various methods applied to investigate L/L interface were outlined briefly. All content are: (1) Working-principle and mechanism of the two technologies at interfacial electrochemistry were discussed in detail; (2) Properties of some important room temperature ionic liquids and their applications as solvents were introduced; (3) Photocurrent responses associated with other electrochemical technologies indicated the superiority of the investigation at liquid/liquid interface; (4) The prospect of the investigation of the antioxidant property. (5) Development of the investigation at cellular activities at the single cell level.2. Applied TLCV method, the reacted system ((ZnTPP(NH₃) - K₄Fe(CN)₆) was investigated at NB/Water interface. As common ion, the role of -ClO₄^- was to control the potential drop at the NB/Water interface and the effects of different concentrations of common ion on ET at interface have been discussed.3. The antioxidant property of AA was demonstrated during the process of electron transfer (ET) and the corresponding effects of AA were visibly affected by using porphyrin zinc with various substitutes as oxidants. As electron-captors, porphyrin zinc molecular obtained the electron came from the electron donor AA and provided various conditions to it, which were perfectly convenient for the simulated antioxidant reaction. The results of the obtained kinetics data showed that the antioxidant property of AA may be affected owing to the difference of the oxidants. Experimental results showed that the two methodologies applied as investigating means to evaluate rate constant of electron transfer achieved and expressed concerns about the simplicity and reliability, and also more vigorous method to study the simulated biomembrane.With the accelerated development of nature science and information technology, investigation of interfacial electrochemistry may encounter more chance and challenge. However, more precise technologies and more reasonable methods destined the broad foreground of understand and deploitation of nature.