| The levels of various reactive oxygens pecies(ROS) in organism have been associated with biologic physiology and pathology. Recognition and quantifying of free radicals are the foundation to study ROS biological functions. In this dissertation, we designed and synthesized a series of ROS probes for detecting and imaging nitric oxide (NO) and peroxide hydrogen (H2O2) by Surface-Enhanced Resonance Raman Scattering (SERS) and Near-infrared Fluorescent. The novel probe has the advantages of easy operation, high sensitivity, especially the predominance of avoiding cell damage and minishing interference by autofluoresence from biological molecules.The main results of this dissertation were shown as follows:1. A novel diamino-azobenzene dye was designed and synthesized as a raman indicator for NO. The raman chemical transformation of the diamino-azobenzene structure is based on the reactivity of diamines with NO in the presence of dioxygen. The N-nitrosation of the diamino-azobenzene, yielding the benzotriazole-based compounds which exhibit a strong propensity to bind to Ag nanoparticles, offers a simple protocol for the direct detection of NO. As the addition of NO, the SERS spectra of the system changed evidently in the range of 1200 nm 1700 nm and turned out a strong SERS peak at 1300 nm. The effect of the concentration of the dye, the aggregation of the nanoparticles and the pH of the solution was evaluated in detail. The result shows that the detection limit of the SERS probe reaches 10-8 mol·L-1 and the system is independent of pH in the range of 4.5～7.5.2. In this report, we presented a novel near-infrared fluorescent probe for H2O2. IR-780 is used as a fluorophore, whose excitation and emission wavelengths are in near-infrared region, and are less absorbed by molecules and can penetrate more deeply into tissues and minimizes cell damage and autofluorescent by excitation light. The new probe are highly sensitive to H2O2 with detection limit of 5.2×10-11 mol·L-1 and well selectively over competing cellular ROS such as superoxide (O2-), nitric oxide (NO), and lipid peroxides.3. A near-infrared fluorescent probe for Ni2+, Cyclam-IR-780, was designed and synthesized, which based on cyclam as the recognition group. The structure of the probe was charactered by 1HNMR and MS. The excitation and emission wavelengths of the as prepared Cyclam-IR-780 were 532 nm and 610 nm, respectively, and its fluorescence intensity increased with the addition of Ni2+ under physiological condition (pH=7.40) and the detection limit reached 1.74×10-7 mol·L-1. Furthermore, this probe has strong anti-interference ability under the existing other metals. At the same time, because of the long excitation wavelength and emission wavelength, the probe could effectively minimize cell damage and minish interference by autofluoresence from biological molecules.
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