The Study On The Analytical Applications Of Fluorescent Small Organic Molecules For The Typical Members In Phosphate Anion Family

Because of the good optical properties, the fluorescent and small organic molecules have been widely applied in the fields of anionic analysis. Specific screening or synthesis of new fluorescent and small organic molecules for anionic recognition and detection supply much more opportunities and challenges in this evolution for supramolecular chemistry in recent years. In this thesis, the typical members in phosphate anion family is the main object of the study. We have discussed the interaction between ST and SHMP, in accordance with changes in spectra of ST, two newly, rapidly and simplely methods was established for SHMP's detection. In addition, fluorescence reagent Salicylaldehyde-o-Aminophenol was synthesized. With the addition of ppi, the fluorescent intensity of Salicylaldehyde-o-Aminophenol was decreased. A direct fluorescence analytical method was proposed to determine the ppi based on the decrease of fluorescent intensity with the increase of the concentration of ppi. The mainly points are as follows:(1) We have respectively researched the interaction between ST and SHMP in the acid HAc-NaAc buffer and alkaline Tris-HCl buffer. The results showed that the absorbency of ST was decreased at 520nm after adding the SHMP, And a new peak appeared at 476 nm in visible absorption spectra. Further found that the fluorescent intensity of ST was decreased at 578nm, but the fluorescent lifetime of the ST is not changed, which showed the fluorescence of ST is statically quenched by SHMP. Based on the change of absorbance, we have established a new method to detect the SHMP. Under the optimized conditions, the linear range was 1.0×10-6 mol/L-1.1×10-5 mol/L with the detection limit of 3.4×10-7mol/L. The application of the established method in the determination of tea drink samples gave a recovery rate of 95.0%-104.0%, with a relative standard deviation of less than 4.6%.(2) In a medium of pH 8.5 tris-HCl buffer, it was found that safranine T (ST) can react with calcein to efficiently produce fluorescence resonance energy transfer (FRET), safranine T get aggregation and its fluorescence receded after adding sodium hexametaphosphat(SHMP), which results in a decrease of the FRET between safranine T and calcein. The ratio of fluorescent intensity at 520nm and 578nm was linear with the concentration of melamine over the range of 3.0×10-6-1.0×10-5 mol/L. the Relative Standard Deviation (RSD) was 3.1% for determination of 6.0×10-6mol/L sodium hexametaphosphat (n=11). The proposed method is high selectively, simply and rapid. it was successfully applied to determine the concentration of two synthetic samples.(3) Fluorescence reagent salicylaldehyde-o-aminophenol was synthesized. In the buffer solution medium of HAc-NaAc at pH 5.0, the reagent can react with ppi more selective than other anions, such as Br-,Cl-,ClO3-,HCO3-,NO3-Pi,SO2-,CTP,GTP,UTP,H2PO4-,ppi. The complex compound made fluorescence intensity decrease and the degree of decreasing was linear with the concentration of ppi. Based on this, a new method for the direct determination of ppi was established. This method could be used to detect synthetic samples, and the recovery was larger than 95%.