茶多酚绿色荧光特性研究

以茶多酚为材料,研究了茶多酚浓度、溶液pH、溶剂、金属离子（Ca²⁺、Al³⁺）和热处理对茶多酚绿色荧光特性的影响。结果表明：以上各因素对荧光强度的影响都极为显著,当溶液pH=7.4±0.2、茶多酚浓度为3βmg/ml或溶剂采用50%乙醇水溶液时,荧光强度达到最大值;金属离子（Ca²⁺、Al³⁺）的直接影响不明显,主要通过影响游离茶多酚浓度而降低其荧光强度;加热处理能显著增大荧光强度。当茶多酚浓度过高（>3βmg/ml）或pH>8时,能导致最大发射峰位置显著红移,其它因素对其影响较小;此外,溶剂极性显著地影响激发峰的形状和荧光强度,但对最大发射峰位置影响较小。

Studies on the Green Fluorescence of Tea Polyphenols

The effects of the concentration , pH, solvent, mental ion ( Ca2 , Al3 ) and heating on the fluorescence spectra of the tea polyphenols were studied. The results showed that the factors of all above had obviously effects on the fluorescent intensity of tea polyphenols. It reached the maximum intensity when pH of solvent is 7.40.2 or the concentration of tea polyphenols is 3 mg/ml or water solution contains 50% ethanol. Adding Ca2 and Al3 in the infusion of tea polyphenols reduced the fluorescent intensity, but it was mainly indirect effect by precipitating a portion of tea polyphenols. Heating treatment caused the fluorescent intensity of tea polyphenols higher. .The maximum emission peak would move to long wavelength when the concentration of tea polyphenols was above 3 mg/ml or pH>8, but other factors had less effects. Besides, solvent polarity affected the shape of excitation fluorescent spectra and the intensity obviously, but had less effect on the maximum emission wavelength.