Optimazing the Illumination in Flash Photolysis
Online registration of gas discharge emission as proof of constant illumination conditions
In many cases the spectrum of an XBO flash lamp is an ideal light source for short-wave excitation of biological materials. The lamps cover continuously a wide range of wavelengths and provide enough energy already starting from 250 nm. Thus, they are more flexible and less expensive than current available lasers, when a desired wavelength is selected. An XBO flash system can be accessed in the millisecond range with repetition rates once a second. In addition to the detection of autofluorescence and to the working on light-sensitive dyes with short-term bleaching characteristics also "Caged compound experiments" can be stimulated in this way.
XBO flash module with spectrometer unit and power
supply in a 19 "rack
© A.S. & Co. GmbH
However, due to the fact that their emission is created by means of electric arcs gas discharge lamps show fluctuations in brightness within the range of about 5%, which furthermore can be accompanied by a modification of its spectral composition. Both factors vary from flash to flash. It is therefore useful to attend the modification process by an online spectrometer control, which is able to register such changes.
SpectraVision of A. S. & Co. provides individual solutions (Modules / Illumination Systems / XBO Illumination for Microscopy) for these workstations. There is the possibility for both to determine the flash frequency and to perform the online verification. If the experimental setup is targeted to the detection of spectral distributions, the oscillations can be correlated directly with a second spectrometer, to which the actual measurement task was assigned. This results in significantly more precise determination of experimental conditions and thus in lower error tolerances. This provides the option to reduce the concentration of substances needed for detecting an effect.