A convenient technique is described for removal of sodium and other metal ion interference from sodium iodide-123 and sodium iodide-124 solutions used to label antibodies. Distillation methods have disadvantages compared to column purification techniques used to remove salt impurities that interfere in radioiodination reactions.
A remote and semi-automated system for hot cell processing of accelerator produced radioactive gases, such as123Xe,77Kr, and211Rn is described. Detailed construction plans and a listing of the mechanical and electronic components are provided.
Gel generators based on Zn, Co, Ni, Mn and Pb tungstates were prepared as potential supports for the development of188Re radiopharmaceuticals. Factors which affected either the elution efficiency of188Re or the breakthrough of188W were examined.188Re was produced as perrenate when the generators were eluted with saline (0.15M NaCl) and different organic solvents. The elution yield of188Re decreased for the various gel supports as: Zn (75%), Co (60%), Ni (37%), Mn (24%), Pb (15%). When a tandem system comprised of a chromatographic alumina column was utilized in combination with the gel generator the188W breakthrough was controlled to of the order of 10–6%.
Since the publication ofRadiochemistry of Germanium (NAS-NS-3043) in 1961, there have been significant developments on the subject. During the period from 1970 to 1980, the diagnostic utilization of the68Ge
68Ga generator system in nuclear medicine stimulated research in the field. In addition, over the past 30 years there have been many advances in the analytical chemistry of germanium (Ge), owing to the rapid increase in application of Ge in the electronics industry and, most recently, as an important component in infrared spectrometers.This fatest review has been completely rewritten. A literature search has been completed through December of 1990. Literature for selected topics has been surveyed through September 1993. The first section contains general information about germanium and its radioisotopes, and relevant nuclear data in tabulated form. In the second section, a general review of the inorganic and analytical chemistry of Ge is presented. Following these two introductory sections, subsequent sections deal with the production and preparation of germanium radioisotopes, separation and determination of Ge, of particular interest to the radiochemist, and selected procedures for its determination in or separation from various media. The section on separation chemistry has been greatly expanded.The review includes sections on hot-atom chemistry and the chemical behavior of carrier-free68Ge. A section entitled Applied Radiochemistry of Germanium deals specifically with68Ge
68Ga generator systems, the role of71Ge in the detection of solar netrinos, and the preparation of68Ge positron sources for studying dislocations in metallic lattices and calibration of Positron Emission Tomography (PET) cameras.Two other noteworthy points follow. Throughout the text, the oxidation state of a metal ion having only one stable state, such as germanium, is not explicitly indicated. Therefore, Ge typically represents Ge4+. Other ions such as arsenic and tin, however, are indicated with their appropriate oxidation states. The term carrier-free applies to radioactive preparations to which no isotopic carrier (stable isotopes) is intentionally added.
A monotypic long-lived radioactive iodine of123I or125I resulting from the123I or125Xe(EC)125I nuclear transformation, respectively, is described. The iodine species has the characteristics thought peculiar to the hydrated
halogen that participates in certain concerted termolecular halogen-halogen reactions. The reaction leading to123ICl or125ICl in gas phase substrates of Cl2, NOCl, HCl and CCl4 was studied.
New165Dy and166Ho macroaggregates(165Dy-MA,166Ho-MA) were prepared by reacting the aqueous solution of165Dy(NO3)3 and166Ho(NO3)3, respectively, with sodium borohydride solution in 0.2N NaOH.165Dy-MA and166Ho-MA are sterile suspension of macroaggregates consisted of Dy/Ho (50–56 wt.%) and boron (5–7%) in saline with mean particle size of 2.6 m (1–8 m range). Both MA could be prepared from the pre-made164Dy-MA and165Ho-MA followed by neutron irradiation. Even though the165Dy-MA and166Ho-MA suspension in saline were stored at 37°C for 24 hrs (Dy-MA), 10 days (Ho-MA) or autoclaved at 121°C for 30 minutes, there was no significant change in particle size and no leakage problem indicating the prepared165Dy-MA and166Ho-MA are sufficiently stable. The results of in-vivo retention studies using rabbits showed high retention (>99.5%) in knee joint even at 24 hrs (165Dy-MA) or at 10 days (166Ho-MA) after administration. Rabbits treated with intra-articular injections of164Dy-MA or165Ho-MA equivalent to 20–30 times the typical clinical dose showed no signs of any toxic effects at 1 month after administration. The ease with which the165Dy-MA and166Ho-MA can be made in the narrow size range and their high in-vitro and in-vivo stability make them attractive agents for radiation synovectomy.
The radiochemistry of aluminum was reviewed for the Sub-Committee on Radiochemistry, National Research Council of the United States National Academy of Sciences. The focus of the review is on nuclear and instrumental methods for analysis of Al in biological and environmental samples. Aluminum is a neurotoxin. Continuing controversy about environmental Al and Alzheimer's Disease has motivated development of ultra-sensitive and precise analysis of samples, since the first review on the radiochemistry of aluminum in 1961. Examples and selected procedures of particular interest to radiochemists are given. Selected topics include tracer applications of28Al and29Al; and AMS for determination of26Al relative to questions asked by cosmochemists and geochemists. Extensive tables provide physical data, stability constants of Al complexes, comparison of analytical methods of analysis of biological samples, and a compilation of results obtained by various techniques for Standard Reference Materials. The literature search was through August, 1995.
An improved188W-188Re gel generator based on Zr tungstate is described. The influence of synthesis parameters and pre-treatment conditions on188Re elution yields and the188W breakthrough was studied with 0.15M aqueous solution of NaCl at pH 5.3 to 7.3 as well as with some organic solvents. An elution efficiency of 80% was achieved during 3 month of explotation with 0.15M NaCl at pH=6.3. The188W breakthrough was 10–4 to 10–3%. The188W breakthrough may be decreased to 10–6% when converted into tandem generator with an alumina column. However,188Re yields are reduced by 8–12% with a tandem generator.