Synthesis And Properties Of Fluorescent Probe For Sulfocompound Based On Pyrenyl Nitroxide

Recently years, for the hydrogen sulfide molecular toxic pollution to environment and its crucial role in regulating biological system, developing fast, highly sensitive, highly selective, more accurate and reliable methods for detecting H2 S have got more and more focus. Design and synthesis hydrogen sulfide fluorescent probe has become a hot topic for its obvious advantage compaired with other hydrogen sulfide detecting methods. Nitroxide, a switch of molecular fluorescence for it can react with hydrogen sulfide, has great development and application potential in detecting hydrogen sulfide because of its special structure and properties. In this paper, we have designed and synthesized a series of nitroxide hydrogen sulfide probe by utilizing pyrene as fluorescent group. We have investigated the structures and the fluorescent performances of these moecule probes in detecting hydrogen sulfide in detail.1. We bonded the nitroxide fragment to the different positions of pyrene and obtained three pyrenyl nitroxide, named as 1-PNIT, 2-PNIT and 4-PNIT. The testing for fluorescent performances of these probes suggested that this type nitroxide response to hydrogen sulfide strongly and will be a kind of very sensitive fluorescent probes for hydrogen sulfide detecting. The limits of detection for 1-PNIT, 2-PNIT and 4-PNIT are 5.276×10-7 M,5.93×10-7 M and 8.959×10-7M, respectively. In terms of selectivity, 1-PNIT interfered with Cys and GSH lightly, while 2-PNIT and 4-PNIT almost without the influence of Cys and GSH. Under neural, weak acid and weak base conditions, all the three probes have good fluorescent performance. In conclusion, these nitroxide fluorescent probes are excellent hydrogen sulfide probe with high selectivity and sensitivity and acceptable p H range of application.2. Through optimized the structure of 4-amino-2,2,6,6-tetramethylpiperidine oxide, We have designed a series novel tert-butyl(pyrenyl)-nitroxide, named as 1-TBPNO, 2-TBPNO and 4-TBPNO. The testing for fluorescent performance of these probes show that tert-butyl(pyrenyl)-nitroxide probes are extremely sensitive to hydrogen sulfide and will be a kind of very sensitive fluorescent probes for hydrogen sulfide detecting. The limits of detection for 1-TBPNO, 2-TBPNO and 4-TBPNO are 1.07×10-7 M?1.379×10-7 M and 1.298×10-7 M, respectively. On the aspect of selectivity, 1-TBPNO interfered with Cys and GSH lightly, while 2-TBPNO and 4-TBPNO almost without influence coming from Cys and GSH. Under neural, weak acid and weak base conditions, all the three probes have good fluorescent performance. In one word, tert-butyl(pyrenyl)-nitroxides are excellent hydrogen sulfide fluorescent probes, they own great development and application potential for their high selectivity and sensitivity and acceptable p H range of application.3. Based on the above types of nitroxides, a thiophene ring was inserted between pyrene ring and imidazole ring and obtained the 1-S-PNIT probe, a benzene ring was inserted between pyrene ring and tert-butyl nitroxide fragment and obtained 1-B-TBPNO, respectively. Compaired with the former nitroxide probes, the sensitivity of 1-S-PNIT declined obviously, while the selectivity is much better. The sensitivity of 1-B-TBPNO probe declined lightly and display special selectivity property. The latter own promising application prospect on hydrogen sulfide detecting for its excellent sensitivity and selectivity compaired with other nitroxide probes.