title: Nickel-63 microirradiators.
abstract: Here we report the fabrication of two types of microirradiators, consisting of a recessed disk and protruding wire with low-beta-energy radionuclide Ni-63 electrodeposited onto a 25 microm diameter Pt wire. Ni-63 is constricted to a small surface area of the microelectrode; hence, this tool provides a means of delivery of localized, large dose density of beta radiation to the object but a minimal dose exposure to the user. The activity levels of Ni-63 emitted from the recessed disk and protruding wire are 0.25 and 1 Bq, respectively. The corresponding beta particles flux levels emitted from the recessed disk and protruding wire are 51 and 11 kBq/cm(2), respectively. These values, measured experimentally using liquid scintillation counting, fit very well the expected values of activity for each microirradiator, calculated considering the self-absorption effect, typical for low-energy beta particles. In order to determine the optimal configuration the dose rates for varying distances from the object were calculated.
authors.affiliation: School of Chemistry and Biochemistry, Georgia Institute of Technology, 901 Atlantic Drive NW, Atlanta, Georgia 30332-0400, USA.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Steeb
authors.forename: Mira
authors.initials: M
authors.lastname: Josowicz
authors.forename: Jiri
authors.initials: J
authors.lastname: Janata
mesh_terms: D001610:Beta Particles / Q000145:classification / Q000627:therapeutic use*; D004307:Dose-Response Relationship, Radiation; D009010:Monte Carlo Method; D009532:Nickel / Q000627:therapeutic use* / Q000633:toxicity; D011829:Radiation Dosage; D011834:Radiation Monitoring; D011835:Radiation Protection; D011868:Radioisotopes / Q000627:therapeutic use* / Q000633:toxicity; D019275:Radiopharmaceuticals / Q000627:therapeutic use / Q000633:toxicity; D018570:Risk Assessment; D012588:Scintillation Counting
chemical_list: D011868:Radioisotopes; D019275:Radiopharmaceuticals; D009532:Nickel