| Three dimensional fluorescence spectral characteristics of tea polyphenols solution,and effects of different concentrations,pH values,buffers,organic solvents and other factors on the visible light region fluorescence were studied by using three dimensional fluorescence spectrometric technology.Results showed that,three dimensional fluorescence spectra of tea polyphenols in H2O could be divided into 3 regions(showed by λex/λem):RegionⅠ:210 nm/315 nm,270 nm/315 nm;Region Ⅱ:335 nm/395 nm；Region Ⅲ:490 nm/515 nm.Excitation and emission wavelengths of the maximum fluorescence shifted towards the longer wavelength with the increase of tea polyphenols concentration.Region Ⅲ fluorescence in visible light region can be sensitively detected at a concentration of 3 mg/mL and pH value of 7.55.Commonly used buffer solutions(e.g.KH2PO4-NaOH buffer,Na2HPO4-citric acid buffer,phosphate buffer and Tris-HCl buffer) have certain degrees of sensitization effect to fluorescence intensity in Region Ⅲ.Polar protic solvents was beneficial for the fluorescence emission in Region Ⅲ.This study could provide new ideas and inspirations for fast,non-destructive analysis and developing application of tea polyphenols. |