2-dimensional fluorescence spectroscopy for on-line bioprocess monitoring

The technique of two-dimensional (2D-) fluorescence spectroscopy covers a w ide range of excitation and emission wavelengths. Several biogenic fluoroph ors (proteins, vitamins and coenzymes) can be detected simultaneously. The development of an optical sensor for on-line measurement of 2D-fluorescence spectra at biotechnological processes is described. This sensor is very we ll suited for in vivo measurements, because it is non-invasive and the an-l ine data can be performed in-situ using an optical light guide system. This instrumentation was used at cultivations of Saccharomyces cerevisiae to sh ow the potential and also the reliability of 2D-fluorescence spectroscopy f or bioprocess monitoring. Changes in cell metabolism (aerobicanaerobic tran sitions), cell growth, medium composition and also turbidity could be detec ted. (C) 1998 Elsevier Science S.A. All rights reserved.