Method and device for measuring process parameters in liquid cultures

A method for determining process parameters using 2D fluorescence spectroscopy in liquid cultures using a device having a plurality of microreactors of at least one microtiter plate, the liquid cultures being held in the microreactors, an orbital shaker configured to agitate the liquid cultures by moving the at least one microtiter plate in an agitating motion at least until completion of cultivation in all of the microreactors, and at least one measuring device configured to record 2D fluorescence spectra of the liquid cultures during the cultivation, the at least one measuring device being decoupled from the agitating motion of the microtiter plate, the method comprising the following steps:

• 1.1 producing monochromatic excitation light, an excitation wavelength of which is modified step by step so that the excitation light is produced with different excitation wavelengths,
• 1.2 successively introducing the excitation light with different excitation wavelengths into the liquid culture in one of the microreactors,
• 1.3 guiding emission spectra from the liquid culture in the one of the microreactors to an optical element that decomposes the emission spectrum for each excitation wavelength into the different individual wavelengths and depicts the emission spectrum fanned out on a sensor matrix of the at least one measuring device with photosensitive sensors to form bands on the sensor matrix for the individual wavelengths,
• 1.4 recording, using the sensor matrix of the at least one measuring device, a 2D fluorescence spectrum by measuring an intensity of the different individual wavelengths of each emission spectrum for each excitation wavelength successively introduced in the liquid culture in the one of the microreactors, and
• 1.5 using steps 1.1-1.4 to record 2D fluorescence spectra of the liquid cultures in further microreactors of the at least one microtiter plate,
• wherein the step of guiding includes selectively modifying a position of the optical element so that a region of the emission spectrum having a wavelength less than or equal to the excitation wavelength is guided past the sensor matrix.