Design, Synthesis And Application Of Fluorescent Probes

In the present work, based on phenazines, rhodamine-B, coumarins, aminonaphthalene, four kinds of fluorescent probes for metal ions, monoamine oxidase and nitric oxide were designed and synthesized.1. Water-soluble bis-triazolyl cycloadducts were synthesized from unknown alkynylated phenazines to serve as selective silver ion sensors. The sensor combined with Ag+in1:1ratio. Examination of the halogenated analogues reveals bathochromic shifts in the absorption and emission spectra because of the ICT. The electron-withdrawing properties of these halogens also result in significantly decreased metal-binding activity of the phenazine cycloadducts. Therefore, the sensing structure-activity relationship of alkynylated phenazine is established.2. A new sensitive trifunctional probe in HEPES solution modulated by pH was reported. At pH6.9, the probe RXY can selectively recognize Hg2+; at pH4.0, it can recognize Pb2+, Cd2+. The mechanism involves a rhodamine lactam ring-opening and a PET process suppression. This sensing platform maybe can be used for designing a bifunctional rhodamine-based fluorescent probe for heavy metals.3. A new fluorescent probe that displays response for both monoamine oxidase type-A (MAO A) and monoamine oxidase type-B (MAO B) is reported. The pH titration shows that the probe could be used for sensing MAO in a wide range of pH. Furthermore, the probe has better sensitivity and shorter response time by comparison with similar probes, and can somewhat distinguish MAO A and MAO B at low concentration.4. Two new analogs NO1and NO2as nitric oxide probes with either lipophilicity or cell;rap ability were synthesized. The result shows that the two probes both can selectively ecognize nitric oxide in phosphate buffer.