Rapid and direct determination of tryptophan in water using synchronous fluorescence spectroscopy

Reynolds, Darren M.

Abstract

Water samples from lakes situated in and around the area of Tsukuba Science City, Ibaraki Prefecture, Japan, were analysed using synchronous fluorescence spectroscopy and HPLC. The spectra revealed a major emission peak (λemm) at 340nm corresponding to an excitation wavelength (λexc) position of 280nm and a Stoke's shift, Δλ=60nm. The fluorescence intensities at these wavelengths were normalised with respect to the water Raman peak, where the λexc was 397nm and the λemm was 453nm, and corrections were introduced to take into account absorption/re-absorption effects of the fluorescing signals caused by the sample matrix. Normalised fluorescence values correlate well with levels of tryptophan present in the samples determined by HPLC analysis (R2=0.99). The relationship of the observed tryptophan-like fluorescence in the water samples to the presence of free tryptophan is discussed. © 2003 Elsevier Science Ltd. All rights reserved.

• Journal Article Type: Article
• Publication Date: Jan 1, 2003
• Journal: Water Research
• Print ISSN: 0043-1354
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 37
• Issue: 13
• Pages: 3055-3060
• DOI: https://doi.org/10.1016/S0043-1354%2803%2900153-2
• Keywords: synchronous fluorescence, tryptophan, lake and drinking water
• Public URL: https://uwe-repository.worktribe.com/output/1069067
• Publisher URL: http://dx.doi.org/10.1016/S0043-1354(03)00153-2
• Additional Information: Additional Information : The work presented in this paper was made possible by a Royal Society Small Equipment Grant entitled Non-invasive monitoring of water. This paper is significant as it one of the first papers to report on the contribution of free tryptophan in surface waters to the observed natural fluorescence properties.