Ion, Xray, UV and Neutron Microbeam Systems for Cell Irradiation A
Total Page:16
File Type:pdf, Size:1020Kb
Ion, XRay, UV And Neutron Microbeam Systems For Cell Irradiation A. W. Bigelow, G. RandersPehrson, G. Garty, C. R. Geard, Y. Xu et al. Citation: AIP Conf. Proc. 1336, 351 (2011); doi: 10.1063/1.3586118 View online: http://dx.doi.org/10.1063/1.3586118 View Table of Contents: http://proceedings.aip.org/dbt/dbt.jsp?KEY=APCPCS&Volume=1336&Issue=1 Published by the American Institute of Physics. Related Articles Design and specifications of the diagnostics for the instrumented calorimeter of Source for the Production of Ions of Deuterium Extracted from Radio frequency plasma Rev. Sci. Instrum. 83, 02B724 (2012) Charge breeding results and future prospects with electron cyclotron resonance ion source and electron beam ion source (invited) Rev. Sci. Instrum. 83, 02A913 (2012) The on-line charge breeding program at TRIUMF's Ion Trap For Atomic and Nuclear Science for precision mass measurements Rev. Sci. Instrum. 83, 02A912 (2012) Transport and emittance study for 18 GHz superconducting-ECR ion source at RCNP Rev. Sci. Instrum. 83, 02A335 (2012) First commissioning results with the Grenoble test electron cyclotron resonance ion source at iThemba LABS Rev. Sci. Instrum. 83, 02A323 (2012) Additional information on AIP Conf. Proc. Journal Homepage: http://proceedings.aip.org/ Journal Information: http://proceedings.aip.org/about/about_the_proceedings Top downloads: http://proceedings.aip.org/dbt/most_downloaded.jsp?KEY=APCPCS Information for Authors: http://proceedings.aip.org/authors/information_for_authors Downloaded 19 Mar 2012 to 129.236.252.4. Redistribution subject to AIP license or copyright; see http://proceedings.aip.org/about/rights_permissions Ion, X-Ray, UV And Neutron Microbeam Systems For Cell Irradiation A.W. Bigelow, G. Randers-Pehrson, G. Garty, C.R. Geard, Y. Xu, A.D. Harken, G. W. Johnson, and D.J. Brenner Center for Radiological Research, Columbia University 630 West 168th Street, 11th floor, New York, NY 10032 Abstract. The array of microbeam cell-irradiation systems, available to users at the Radiological Research Accelerator Facility (RARAF), Center for Radiological Research, Columbia University, is expanding. The HVE 5MV Singletron particle accelerator at the facility provides particles to two focused ion microbeam lines: the sub-micron microbeam II and the permanent magnetic microbeam (PMM). Both the electrostatic quadrupole lenses on the microbeam II system and the magnetic quadrupole lenses on the PMM system are arranged as compound lenses consisting of two quadrupole triplets with “Russian” symmetry. Also, the RARAF accelerator is a source for a proton-induced x-ray microbeam (undergoing testing) and is projected to supply protons to a neutron microbeam based on the 7Li(p,n)7Be nuclear reaction (under development). Leveraging from the multiphoton microscope technology integrated within the microbeam II endstation, a UV microspot irradiator – based on multiphoton excitation – is available for facility users. Highlights from radiation-biology demonstrations on single living mammalian cells are included in this review of microbeam systems for cell irradiation at RARAF. Keywords: Radiation biology, microbeam, x-ray, UV, neutron PACS: 87.53.-j INTRODUCTION MICROBEAM SYSTEMS AT THE RADIOLOGICAL RESEARCH Single-cell / single-particle microbeam irradiation ACCELERATOR FACILITY technology at Columbia University’s Radiological Research Accelerator Facility (RARAF) has evolved Microbeam platforms at Columbia University’s continuously starting with the user facility’s initial 1 Radiological Research Accelerator Facility (RARAF) aperture-based microbeam system installed in have evolved from an initial aperture-based February 1994. RARAF’s first microbeam system microbeam (decommissioned) to an array of micron- pioneered numerous radiobiology studies in particle- sized irradiation probes. Our microbeam platforms are: induced DNA damage and repair mechanisms. The microbeam II (electrostatic focusing system), the dominant interest among RARAF’s users is basic 2 Permanent Magnetic Microbeam (PMM), an x-ray research involving the bystander effect , where non- microbeam, the neutron microbeam (under targeted cell nuclei manifest damage similar to development), and the UV microspot. All these targeted cell nuclei. In investigating cell-signaling systems have a common irradiation protocol that pathways such as those potentially associated with the involves imaging, targeting and irradiating. In short: bystander effect, cell biologists at RARAF pursue 1) cells are imaged and their center-of-gravity fundamental understanding of low-dose effects. coordinates are registered within the control program, Highlights from radiation-biology demonstrations on 2) cells are accurately positioned at the irradiation single living mammalian cells are included in this location, 3) cells are irradiated with a prescribed review of microbeam systems for cell irradiation at radiation dose, and 4) the next cell is brought to the RARAF. irradiation location. Application of Accelerators in Research and Industry AIP Conf. Proc. 1336, 351-355 (2011); doi: 10.1063/1.3586118 © 2011 American Institute of Physics 978-0-7354-0891-3/$30.00 351 Downloaded 19 Mar 2012 to 129.236.252.4. Redistribution subject to AIP license or copyright; see http://proceedings.aip.org/about/rights_permissions Microbeam II As DNA damage occurred in the cell nucleus, XRCC1 repair protein formed foci at the damage sites. RARAF’s principal microbeam system, microbeam Immediately after the irradiation, a Z-stack of 21 wide- II, uses an electrostatic quadrupole lens system field fluorescent images was acquired using a water- capable of producing a submicron-diameter focused dipping objective (60X 1.0NA), and a step size of ΔZ beam in air3. The electrostatic lens system is a = 0.5 µm, to reveal GFP concentrations in the nucleus compound quadrupole triplet lens system designed exposed with the “NIH” pattern and in the neighboring with Russian symmetry by A. Dymnikov4. Incentives (control) cell nuclei. Autoquant software was used to for developing a microbeam system with a focused ion deblur the images in a post-processing step – result beam were: a) to overcome the penumbra or halo shown in Figure 1. artifact associated with aperture-based microbeam systems and b) to improve beam rate at target. While a Permanent Magnetic Microbeam sharp submicron beam spot is compatible with irradiating sub-cellular structures, we demonstrate the The permanent magnetic microbeam (PMM)5 horizontal-plane positioning stability of the vertical shown in figure 2 is a second focused charged-particle microbeam II ion beam in the section below. microbeam developed at RARAF. It uses permanent magnetic quadrupole lenses (STI Optronics, Inc., Microbeam II Demonstration Bellevue, WA) whose strengths are tunable by varying the insertion of permanent magnets into the shaped To demonstrate the resolution of the microbeam II yokes6. Originally designed as a stand-alone irradiator at RARAF, the letters “NIH” were irradiated microbeam with a 210Po source, the system remains onto a single live cell nucleus. The cells for this tethered to its accelerator-based test source of ions demonstration were HT1080 human Fibro Sarcoma following media attention of the 210Po-linked cell nuclei containing GFP-tagged XRCC1 (single- assassination of Alexander Litvinenko in November strand DNA repair protein). These cells were provided 20067 that led to heightened security and reduced by David Chen, UT Southwestern, Dallas, Texas; they availability of polonium. The use of an accelerator- were plated on microbeam dishes and kept under based ion source allows for higher beam rate and, due physiological conditions during the irradiation and to reduced chromatic aberrations, a smaller spot size imaging phases. A single cell nucleus was irradiated in than would be available with a 210Po source. With the an “NIH” dot-matrix stage-motion pattern with ~200 PMM fully functional as a second charged-particle 6-MeV alpha particles per spot. The pattern was microbeam line at RARAF, its design concept as a reproduced via precision stage motions to irradiation stand-alone microbeam is still valid and potentially locations. Typical spacing between points along each more economical for radiation-research laboratories letter was 1 µm. because it excludes purchase of a particle accelerator and support electronics. Contrary to electrostatic or electromagnetic lenses, the PMM requires neither high precision voltage/current supplies nor cooling. The use of permanent magnets also allows a much tighter pole- face gap, providing better optical properties compared to electromagnetic lenses. Presently, the PMM is used for cell-irradiation experiments when development projects occupy the microbeam II endstation or beamline. Also, the PMM is used for development of point & shoot technology as well as microfluidics-based flow and shoot technology (FAST). Impetus for a point & shoot device is increased throughput. Pointing the beam with electromagnetic steering coils to cellular targets within a frame of view relies on electronic switching, which is inherently faster than moving a mechanical stage. FIGURE 1. “NIH” written on a single cell nucleus with the Toward that end, a wide-field magnetic split-coil RARAF microbeam. A tribute to our primary funding deflector system (Technisches Büro Fischer, Ober agency and a demonstration of our microbeam resolution. Ramstadt, Germany) was integrated into the PMM beamline. FAST developments are in collaboration with Dr. Daniel