Chemical Research in Chinese Universities ›› 2009, Vol. 25 ›› Issue (6): 966-970.

• Research Note • Previous Articles    

Capacity of Tea Scavenging Singlet Oxygen Studied by Means of 1,3-Diphenylisobenzofuran as Fluorescence Probe

LÜ Qing-luan, YUE Ning-ning, ZHANG Miao, GONG Bin and WANG Huai-you*   

  1. College of Chemistry, Chemical Engineering and Materials Science, Shandong Normal University, Jinan 250014, P. R. China
  • Received:2008-10-14 Revised:2008-12-28 Online:2009-11-25 Published:2010-01-25
  • Contact: WANG Huai-you. E-mail: wanghuaiyou@sdnu.edu.cn
  • Supported by:

    Supported by the Natural Science Foundation of Shandong Province, China(No.Y2006B31).

Abstract:

In this study, we present a spectrofluorimetric method of estimating scavenging effect of tea leaf on singlet oxygen(1O2) using 1,3-diphenylisobenzofuran (DPBF) as fluorescence probe. 1O2 generated by irradiation of methylene blue (MB) could oxidize DPBF resulting in its fluorescence quenching at 447 nm, however, the relative fluorescence intensity of DPBF in the system would recover in the presence of antioxidant which could scavenge 1O2. So, We could evaluate the scavenging capacity of tea leaf to 1O2 according to the recovery extent of the relative fluorescence intensity of DPBF, which was a simple, precise and selective method. Effects of pH, reagent concentration, foreign substances, reaction time on the reaction system had been discussed and the availability of proposed method was confirmed by adding NaN3 into the system, which was a potent quencher of 1O2.

Key words: Singlet oxygen; 1,3-Diphenylisobenzofuran; Methylene blue; Tea leaf; Fluorescence quenching