Microspectrophotometer
Overview
The CryoBench microspectrophotometer allows to record UV/vis absorption, fluorescence, or Raman spectra of a protein crystal which is mounted on a goniometer head installed at the center of three objectives.
Through these objectives, light sources like deuterium or halogen lamps or lasers can be focussed onto a sample, and the transmitted or scattered light from the sample is lead to a UV/vis absorption spectrometer or photomultiplier for analysis. Two of these objectives are oriented in transmission geometry (180°), while the third one is at 90° for fluorescence experiments. Transmission of light to and from these objectives happens through optical fibers.
Typically, the sample is frozen at 100 K by a cryostream (Oxford Cryosystem 700), but measurements at room temperature are also possible.
Experimental setup
Microspectrophotometer: three objectives, a Raman head, a video microscope, and a cryostream are arranged around a sample mounted on a central goniometer.
Goniometer
The goniometer is controlled via a joystick device on the optical table.
Cryostream
Usually, the cryostream device is set to operate at a constant temperature of 100 K. However, it is also possible to run defined ramping programs, either by programming the controller manually or through a LabView application.