title: Spatial distribution of Auger electrons emitted from internalised radionuclides in cancer cells: the photoresist autoradiography (PAR) method.
abstract: Microdosimetric evaluation of Auger electron-emitting radionuclides involves a detailed evaluation of energy deposition at a nanometre scale. To perform Monte Carlo modelling of such energy deposition, accurate information regarding the spatial distribution of the radionuclide is required. A recent addition to the methods for determining the spatial distribution of cellular internalised radionuclides is based on detection in a polymer photoresist (e.g. polymethyl methacralate), followed by atomic force microscopy analysis of the resultant 3D pattern. In comparison with present practice, the method offers greater spatial resolution and improved quantification. The volume of the pattern is proportional to the total dose, thereby permitting assessment of variability of accumulated activity, while the variation in depth across the pattern reflects the lateral spatial distribution in the local fluence per unit area. An added advantage is the similarity in response to ionising radiation of an organic polymer compared to that of biological material. A pattern in the resist from radiation emitted by a radionuclide treated cell gives additional spatial information about the energy deposited in the resist.
authors.affiliation: Cancer Research UK and Medical Research Council Oxford Institute for Radiation Oncology, University of Oxford, Oxford, UK.
authors.forename: G
authors.initials: G
authors.lastname: Royle
authors.affiliation: Department of Material Science, University of Oxford, Oxford, UK.
authors.forename: S
authors.initials: S
authors.lastname: Myhra
authors.affiliation: Department of Material Science, University of Oxford, Oxford, UK.
authors.forename: R
authors.initials: R
authors.lastname: Chakalova
authors.affiliation: Cancer Research UK and Medical Research Council Oxford Institute for Radiation Oncology, University of Oxford, Oxford, UK.
authors.forename: K A
authors.initials: KA
authors.lastname: Vallis
authors.affiliation: Cancer Research UK and Medical Research Council Oxford Institute for Radiation Oncology, University of Oxford, Oxford, UK Department of Biomedical Science, Tshwane University of Technology, Pretoria, South Africa nadia.falzone@oncology.ox.ac.uk.
authors.forename: N
authors.initials: N
authors.lastname: Falzone
mesh_terms: D001345:Autoradiography; D002294:Carcinoma, Squamous Cell / Q000000981:diagnostic imaging*; D004583:Electrons; D006258:Head and Neck Neoplasms / Q000000981:diagnostic imaging*; D006801:Humans; D007205:Indium Radioisotopes / Q000378:metabolism*; D018625:Microscopy, Atomic Force / Q000379:methods*; D019904:Polymethyl Methacrylate / Q000737:chemistry / Q000528:radiation effects; D011877:Radionuclide Imaging; D014407:Tumor Cells, Cultured
chemical_list: D007205:Indium Radioisotopes; D019904:Polymethyl Methacrylate