BioXAS Fall shutdown Update

Many improvements to the storage ring and beamlines are happening during the fall shutdown at the CLS. At BioXAS, engineers and technicians are installing a new air conditioning system to keep the optical elements, detectors, and electronics operating within their optimal temperature ranges. This will increase beam stability and improve the detector signal to noise ratio. The work will be completed for the start of cycle 33 in January 2021. Pictures of the AC installation

Advanced XAS Workshop 2020 registrations are now closed

The registrations for the Advanced XAS Workshop 2020 are now closed, but you can still submit your information to be considered for the next iteration of the workshop, which will be conducted at a later date still to be decided, certainly more than a year from now.

Call for Proposal for Jan-Jul 2021 Now Open!

We are pleased to announce that our next Call for Proposals for Cycle 33, which runs from January 1 to June 30, 2021, is now open! See Applying for Beamtime for Information on how to submit Proposal to BioXAS-Spectroscopy.

Due to COVID-19 BioXAS moves to Drop-in/Mail-in mode exclusively

Due to COVID-19 CLS is now only accepting samples mailed in, or dropped in, and no external users are allowed on-site. The measurements will be conducted by the staff, but soon it will be possible for users to control the experiments remotely. Details on the Mail-in program can be found at Contact the Beamline staff for more details if necessary.

BioXAS Spectroscopy Beamlines

There are two Hight-Sensitivity Spectroscopy Beamlines at BioXAS: Main and Side. They were specially designed to measure the XAS spectra of transition elements in bulk Biological samples with very diluted concentrations. In practice, this means the photon flux is usable from 5 to 32 keV (it peaks at ~12 keV), and that they have very sensitive fluoresce detectors. These makes the beamlines also very capable for Material and Environmental Science studies as well, where the concentration of the elements of interest are typically higher than in biological samples, so they are easier to measure.



  • x-ray absorption near edge structure (XANES)
  • Extended X-ray absorption fine structure (EXAFS)


Example Research Areas 

  • Chemical forms of trace elements, metals, and metalloids in purified metalloproteins isolated from various biological tissues; for example, human disease specimens, plants, toxic wastes
  • Speciation of toxic elements in mine impacted environment
  • Speciation and crystal structure investigation of materials with applications as semiconductors, memory shape alloys, and catalyzers, among others. 

Due to COVID-19, all experiments at CLS as of now can be only conducted by the staff or by remote access, after mailing-in or dropping-in the samples at our facilities. If you get beamtime talk to the staff to coordinate.