A Novel Fluorescent Probe For The Stent To The Artificial Simulation Of Sod Activity Center Complex Design, Preparation In Bioanalysis Applications

Various reactive oxygen species (ROS) are generated in cells in the course of biological metabolism, such as superoxide (O2-.), hydroxyl radical (HO·), singlet oxygen (1O2), hydrogen peroxide (H2O2), nitric oxide (NO) and peroxynirte (ONOO-). These ROS exist in organisms widely and participate in modulating major physiological and pathological processes. Oxidative stress caused by the destruction of the balance between the generation and metabolism of ROS is directly related to cancer, inflammation, tissular damage and apoptosis signal transmit. It has become the research focus in the area of fundamental medicine and life sciences.However, the short live and high reactivity of ROS in organisms result in the steady-state concentration of ROS usually very low, and it can hardly be capture, especially the determination in vivo and in situ has no breakthrough. In addition, there exist the anti-oxidation systems preventing the damages of free radicals in organisms. Up to date, it cannot be observed directly the dynamic generation of reactive oxygen species in some tissues. Enough cognition and sufficient experimental evidences of their generation mechanism, physiological action and dynamic damages on organisms are not acquired. Therefore, the therapy effects of many diseases in clinic are limited. So it is one of challenging scientific researches in analytical chemistry, in which novel high sensitivity, high selectivity quantitative analysis and determination technologies which can dynamic trace reactive oxygen species in vivo need to be developed.In the present, the methods of the determination of free radicals include electron spin resonance (ESR), high performance liquid chromatography (HPLC), chemiluminescence (CL) and electrochemistry. Compared to the above methods, fluorescence spectroscopy combined with confocal laser scanning microscopy is the exclusive detection method which can realize the"real-time, visible, quantitative"determination of reactive oxygen species in living cells and tissues. Near-infrared (NIR) light at around 600-1000 nm is less absorbed than visible light by biological substances, and can penetrate more deeply into tissues. Moreover, it has the further advantage that autofluorescence is not observed upon NIR excitation. NIR fluorescent bioimaging is one of the most fascinating fields in chemical biology, offering research challenges and opportunities. Therefore, the design and synthesis of infrared, neat-infrared fluorescent probe which has high selectivity, sensitivity and compatibility is one of challenging scientific researches in life chemistry. In recent years, accompanied by the development of fluorescence spectroscopy in biochemistry, medicine, and chemical research, many fluorescent probes have been used in a variety of biological analysis. At present, the main types of fluorescent probes include organic small molecules, nano-probe, lanthanide complexes as well as molecular beacons and protein. Among them, enzyme stain fluorescent probes are used to detect various physiological activities of enzyme by its unique advantages, especially in detecting the complicated conformation change processes of enzyme. The investigation of enzyme conformation and the interaction between enzyme and small molecules or biological macromolecules will elucidate the transformation mechanism of organisms in physiological or pathological conditions. It is of great significance in revealing the mystery of life, clinical diagnostics and drug screening.In this paper, a new kind of near-infrared fluorescence probe was designed for the detection of superoxide anion specifically, based on the structure of artificial enzyme complexes of SOD active center. The probe connects rhodamine with artifical enzyme complex, and utilizes the conformational change of SOD active center during the dismutation of superoxide anion to realize the change of the fluorescent intensity of fluorophore. It's used for detecting superoxide anion high specifically and high sensitivity and establishing a real-time, online, quick and accurate determination of superoxide anion in vivo analysis.