title: Ultraviolet germicidal irradiation and its effects on elemental distributions in mouse embryonic fibroblast cells in x-ray fluorescence microanalysis.
abstract: Rapidly-frozen hydrated (cryopreserved) specimens combined with cryo-scanning x-ray fluorescence microscopy provide an ideal approach for investigating elemental distributions in biological cells and tissues. However, because cryopreservation does not deactivate potentially infectious agents associated with Risk Group 2 biological materials, one must be concerned with contamination of expensive and complicated cryogenic x-ray microscopes when working with such materials. We employed ultraviolet germicidal irradiation to decontaminate previously cryopreserved cells under liquid nitrogen, and then investigated its effects on elemental distributions under both frozen hydrated and freeze dried states with x-ray fluorescence microscopy. We show that the contents and distributions of most biologically important elements remain nearly unchanged when compared with non-ultraviolet-irradiated counterparts, even after multiple cycles of ultraviolet germicidal irradiation and cryogenic x-ray imaging. This provides a potential pathway for rendering Risk Group 2 biological materials safe for handling in multiuser cryogenic x-ray microscopes without affecting the fidelity of the results.
authors.affiliation: Department of Physics & Astronomy, Northwestern University, Evanston, Illinois, USA.
authors.forename: Qiaoling
authors.initials: Q
authors.lastname: Jin
authors.affiliation: X-ray Science Division, Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois, USA.
authors.forename: Stefan
authors.initials: S
authors.lastname: Vogt
authors.affiliation: X-ray Science Division, Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois, USA.
authors.forename: Barry
authors.initials: B
authors.lastname: Lai
authors.affiliation: X-ray Science Division, Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois, USA.
authors.forename: Si
authors.initials: S
authors.lastname: Chen
authors.affiliation: X-ray Science Division, Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois, USA.
authors.forename: Lydia
authors.initials: L
authors.lastname: Finney
authors.affiliation: X-ray Science Division, Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois, USA.
authors.forename: Sophie-Charlotte
authors.initials: SC
authors.lastname: Gleber
authors.affiliation: X-ray Science Division, Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois, USA.
authors.forename: Jesse
authors.initials: J
authors.lastname: Ward
authors.affiliation: Department of Physics & Astronomy, Northwestern University, Evanston, Illinois, USA.
authors.forename: Junjing
authors.initials: J
authors.lastname: Deng
authors.affiliation: Department of Physics & Astronomy, Northwestern University, Evanston, Illinois, USA.
authors.forename: Rachel
authors.initials: R
authors.lastname: Mak
authors.affiliation: APS Engineering Support Division, Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois, USA.
authors.forename: Nena
authors.initials: N
authors.lastname: Moonier
authors.affiliation: Department of Physics & Astronomy, Northwestern University, Evanston, Illinois, USA; X-ray Science Division, Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois, USA; Chemistry of Life Processes Institute, Northwestern University, Evanston, Illinois, USA.
authors.forename: Chris
authors.initials: C
authors.lastname: Jacobsen
mesh_terms: D000818:Animals; D015925:Cryopreservation; D004577:Electron Probe Microanalysis / Q000379:methods; D053595:Embryonic Stem Cells / Q000737:chemistry / Q000528:radiation effects*; D005347:Fibroblasts / Q000737:chemistry / Q000528:radiation effects*; D051379:Mice; D008856:Microscopy, Fluorescence; D014466:Ultraviolet Rays / Q000009:adverse effects*