title: Detection of atomic scale changes in the free volume void size of three-dimensional colorectal cancer cell culture using positron annihilation lifetime spectroscopy.
abstract: Positron annihilation lifetime spectroscopy (PALS) provides a direct measurement of the free volume void sizes in polymers and biological systems. This free volume is critical in explaining and understanding physical and mechanical properties of polymers. Moreover, PALS has been recently proposed as a potential tool in detecting cancer at early stages, probing the differences in the subnanometer scale free volume voids between cancerous/healthy skin samples of the same patient. Despite several investigations on free volume in complex cancerous tissues, no positron annihilation studies of living cancer cell cultures have been reported. We demonstrate that PALS can be applied to the study in human living 3D cell cultures. The technique is also capable to detect atomic scale changes in the size of the free volume voids due to the biological responses to TGF-β. PALS may be developed to characterize the effect of different culture conditions in the free volume voids of cells grown in vitro.
authors.affiliation: Department of Electricity and Electronics, University of the Basque Country - UPV/EHU, Leioa, Basque Country, Spain.
authors.forename: Eneko
authors.initials: E
authors.lastname: Axpe
authors.affiliation: Immunogenetics Research Laboratory, BioCruces Research Institute, Barakaldo, Basque Country, Spain.
authors.forename: Tamara
authors.initials: T
authors.lastname: Lopez-Euba
authors.affiliation: Immunogenetics Research Laboratory, BioCruces Research Institute, Barakaldo, Basque Country, Spain ; Department of Genetics, Physical Anthropology and Animal Physiology, University of the Basque Country - UPV/EHU, Leioa, Basque Country, Spain.
authors.forename: Ainara
authors.initials: A
authors.lastname: Castellanos-Rubio
authors.affiliation: Department of Applied Physics II, University of the Basque Country - UPV/EHU, Leioa, Basque Country, Spain.
authors.forename: David
authors.initials: D
authors.lastname: Merida
authors.affiliation: Department of Applied Physics II, University of the Basque Country - UPV/EHU, Leioa, Basque Country, Spain.
authors.forename: Jose Angel
authors.initials: JA
authors.lastname: Garcia
authors.affiliation: Immunogenetics Research Laboratory, BioCruces Research Institute, Barakaldo, Basque Country, Spain ; Department of Genetics, Physical Anthropology and Animal Physiology, University of the Basque Country - UPV/EHU, Leioa, Basque Country, Spain.
authors.forename: Leticia
authors.initials: L
authors.lastname: Plaza-Izurieta
authors.affiliation: Immunogenetics Research Laboratory, BioCruces Research Institute, Barakaldo, Basque Country, Spain ; Department of Genetics, Physical Anthropology and Animal Physiology, University of the Basque Country - UPV/EHU, Leioa, Basque Country, Spain.
authors.forename: Nora
authors.initials: N
authors.lastname: Fernandez-Jimenez
authors.affiliation: Department of Electricity and Electronics, University of the Basque Country - UPV/EHU, Leioa, Basque Country, Spain.
authors.forename: Fernando
authors.initials: F
authors.lastname: Plazaola
authors.affiliation: Immunogenetics Research Laboratory, BioCruces Research Institute, Barakaldo, Basque Country, Spain ; Department of Genetics, Physical Anthropology and Animal Physiology, University of the Basque Country - UPV/EHU, Leioa, Basque Country, Spain.
authors.forename: Jose Ramon
authors.initials: JR
authors.lastname: Bilbao
mesh_terms: D018929:Cell Culture Techniques; D045744:Cell Line, Tumor; D015179:Colorectal Neoplasms / Q000473:pathology*; D006801:Humans; D008856:Microscopy, Fluorescence; D013057:Spectrum Analysis / Q000379:methods*; D018874:Spheroids, Cellular / Q000473:pathology*; D014407:Tumor Cells, Cultured