Bismuth-213 is a radionuclide of interest for targeted alpha therapy and is supplied via a radiochemical generator system through the decay of 225Ac. Radionuclide generators employ longer lived \"parent\" radionuclides to routinely supply shorter-lived \"daughter\" radionuclides. The traditional 225Ac/213Bi radiochemical generator relies on an organic cation exchange resin where 225Ac binds to the resin and 213Bi is routinely eluted. These resins degrade when they absorb large doses of ionizing radiation (>1 × 106 Gy/mg), which has been observed when the loading activity of 225Ac exceeds 2.59*109 Bq (70 mCi). Herein we report the development of an electrochemical generator for the supply of 213Bi that has the potential to overcome this limitation. Bismuth-213 spontaneously electrodeposits onto nickel foils in 0.1 M hydrochloric acid at 70 °C. Using this method, we were able to plate an average of 73 ± 4 % of the 213Bi in solution and obtain a final 213Bi recovery of 65 ± 8 % in 0.1 M citrate pH 4.5 via reverse electrolysis using titanium as the cathode. The recovered 213Bi had an average radiochemical purity of >99.8 % and was successfully used to radiolabel DOTATATE with an average radiochemical yield of 85.1 % (not optimized).

The quest to improve the quality of nuclear data, such as half-lives, transition yields, and reaction cross-sections, is a shared endeavor among various areas of nuclear science. 48V is a vanadium isotope for which experimental data on neutron reaction cross-sections is needed. However, traditional isotope production techniques cannot produce 48V with high enough isotopic purity for some of these measurements. \"Isotope harvesting\" at the Facility for Rare Isotope Beams (FRIB) is a new isotope production technique that could potentially yield 48V with the necessary purity for such studies. In this case, 48Cr would be collected and allowed to generate 48V that can be separated from undecayed 48Cr to yield highly pure 48V. Thus, any protocol for producing pure 48V via isotope harvesting would involve utilizing a separation technique that can effectively separate 48Cr and 48V. In this study, the radiotracers 51Cr and 48V were used to develop possible radiochemical separation methodologies, which can be translated to obtain high purity 48V via this novel isotope production method. The developed protocols utilize either ion exchange or extraction chromatographic resins. Separations of 51Cr and 48V with AG 1-X8 anion exchange resin respectively resulted in recoveries of 95.6(26)% and 96.2(12)% with radionuclidic purities of 92(2)% and 99(1)%. An even more effective Cr and V separation was obtained with an extraction chromatographic resin (TRU resin) and 10 M HNO3 loading solution. Here, 51Cr and 48V respectively had recoveries of 94.1(28)% and 96.2(13)% with high radionuclidic purities (100(2)% and 100(1)%) in small volumes (8.81(8) mL and 5.39(16) mL). This study suggests that, to maximize the yield and isotopic purity of 48V, the best production protocol would involve utilizing two separations with TRU resin and 10 M HNO3 to isolate 48Cr and purify the generated 48V.

A radionuclide generator of the short-lived alpha emitter 226Th was proposed. An original scheme consisting of two in-series chromatographic columns was developed for rapidly producing a neutral citric-buffered eluate of high purity 226Th. The first column filled with TEVA resin retained the parent 230U, while 226Th was eluted with 7 M HCl solution to be immediately adsorbed on the second column containing DGA resin or UTEVA resin. Having substituted the strongly acidic medium of second column with neutral salt solution, 226Th was desorbed with diluted citric buffer solution. One cycle of generator milking took 5-7 min and produced >90% of 226Th in 1.5 mL of eluate (pH 4.5-5.0) appropriate for direct use in radiopharmaceutical synthesis. The 230U impurity in 226Th eluate was less than 0.01%. The proposed two-column 230U/226Th generator was tested over 2 months including a second loading of 230U additionally accumulated from 230Pa.

Radiotracer techniques are extensively used for troubleshooting, measuring hydrodynamic parameters and process visualization in industrial systems because of their many advantages over conventional tracer techniques. Most of these techniques are well established, and are routinely used in the industry around the world. This review discusses the general principles of the radiotracer methodology, commonly used applications of radiotracer in the industry, recent advances in the area, and the economic benefits accrued. Each application is illustrated with recently published case studies.

Over the last decade, targeted alpha therapy has demonstrated its high effectiveness in treating various oncological diseases. Lead-212, with a convenient half-life of 10.64 h, and daughter alpha-emitter short-lived 212Bi (T1/2 = 1 h), provides the possibility for the synthesis and purification of complex radiopharmaceuticals with minimum loss of radioactivity during preparation. As a benefit for clinical implementation, it can be milked from a radionuclide generator in different ways. The main approaches applied for these purposes are considered and described in this review, including chromatographic, solution, and other techniques to isolate 212Pb from its parent radionuclide. Furthermore, molecules used for lead\'s binding and radiochemical features of preparation and stability of compounds labeled with 212Pb are discussed. The results of preclinical studies with an estimation of therapeutic and tolerant doses as well as recently initiated clinical trials of targeted radiopharmaceuticals are presented.

The application of diagnostic and therapeutic radionuclides in nuclear medicine has grown significantly and has translated into the increased interest in radionuclide generators and their development. 224Ra and its shorter-lived daughters, 212Pb and 212Bi, are very interesting radionuclides from Targeted Alpha Therapy point of view for treatment of small cancers or metastatic forms. The purpose of the present work was to develop a simple generator for rapid elution of carrier-free 224Ra from 232U or 228Th sources by radiochemical separation based on extraction chromatography with the utilization of a home-made material. The bis(2-ethylhexyl) hydrogen phosphate (HDEHP) extractant was immobilized on polytetrafluroethylene (PTFE) grains and its ability to selectively adsorb 232U and 228Th, with simultaneous high elution recovery of 224Ra, was checked over few years. The 224Ra was quantitatively eluted with small volume (3-5 mL) of 0.1 M HNO3 with low breakthrough (<0.005%) and was used for further milking of 212Bi and 212Pb from DOWEX 50WX12 by 0.75 M and 2.0 M HCl, respectively. The elaborated here methods allowed high recovery of 224Ra, 212Pb and 212Bi radionuclides and their application in radiolabeling of various biomolecules.

Auger electron therapy is an attractive modality for targeting microscopic tumors. Rhodium-103 m (103mRh, T½ = 56.1 min) is a promising Auger electron emitter that can be obtained as the decay product of palladium-103 (103Pd, T½ = 16.99 days). 103Pd was chelated in a lipophilic derivative of the 16aneS4 macrocycle and the complex was trapped on a C18 cartridge. Elution with dilute hydrochloric acid gave radiochemically pure 103mRh. We hypothesize this to be through a combination of the Szilard-Chalmers effect and transient ionization.

An anion exchange method was developed to separate selenium and arsenic for potential utility in a (72)Se/(72)As generator. The separation of the daughter (72)As from the (72)Se parent is based on the relative acid-base behavior of the two oxo-anions in their highest oxidation states. At pH 1.5, selenate is retained on strongly basic anion exchange resin as HSeO4(-) and SeO4(2-), while neutral arsenic acid, H3AsO4, is eluted.