Singlet Oxygen Involved Luminol Chemiluminescence Catalyzed by Graphene Oxide

• Published in: Journal of physical chemistry. C 2012-10, Vol.116 (40), p.21622-21628
• Main Authors: Wang, Dong Mei, Zhang, Yan, Zheng, Lin Ling, Yang, Xiao Xi, Wang, Yi, Huang, Cheng Zhi
• Format: Article
• Language: English
• Subjects: Chemiluminescence; Chemistry; Exact sciences and technology; General and physical chemistry
• ISSN: 1932-7447; 1932-7455
• DOI: 10.1021/jp306061u

Singlet oxygen (1O2) in the chemiluminescence (CL) of luminol has been rarely involved. In this work, graphene oxide (GO) was prepared and at first found to enhance the CL of luminol-H2O2 system in a weakly alkaline medium mainly through the intermediate of 1O2, which was greatly different from the traditional catalyst in such CL system that occurred in a strongly basic medium through the intermediates such as superoxide anion radical (O2 ·–) and hydroxyl radical (OH·). With the aid of CL spectral, UV–visible absorption spectral, and electron spin resonance (ESR) spectral measurements and investigations on the effects of various free radical scavengers on the GO-enhanced luminol CL, we identified the acceleration role of GO played in the electron-transfer processes and efficient catalysis on the decomposition of H2O2, generating a high yield of 1O2 on the surface of GO. The resulted 1O2 then reacted with luminol, producing an endoperoxide, which decomposed to the excited-state 3-aminophthalate anions (3-APA*), giving rise to light emission with the maximum wavelength at 440 nm. As a result, this 1O2 -induced luminol CL, owing to the catalysis by GO, could have six-fold enhancement compared with that in the absence of GO. These investigations could be further extended to the use of GO as an amplified label for the CL determinations of H2O2 and glucose. The significant features of this GO-catalyzed luminol CL may open up new opportunities for its potential applications in a wide range of fields.