Experimental Therapeutics Using Alpha Particles

Abstract

Because of their limited path length and the high LET nature of the emitted radiations, alpha emitters are particularly wellsuited for selective cell destruction if appropriate carrier molecules can be identified. Among the potential carriers for alpha emitters are steroid hormones and melanin precursors. The development of rapid stereo-specific labeling and separation procedures for astatine labeled radiopharmaceuticals will play a critical role in implementing these strategies.

α‐Emitting cancer therapy using 211At‐AAMT targeting LAT1

“…211 At‐AAMT was synthesized via mercuration of AMT, as previously reported 23,24 . AMT was purchased from Watanabe Chemical Industries, Ltd., and other chemicals were purchased from the FUJIFILM Wako Pure Chemical Corporation.…”

“…211 At-AAMT was synthesized via mercuration of AMT, as previously reported. 23,24 AMT was purchased from Watanabe Chemical Industries, Ltd., and other chemicals were purchased from the Millipore; solvent: n-butanol/acetic acid/water (4/1/1)), and the radioactivity on the plate was measured using a Typhoon FLA7000 biomolecular imager (GE Healthcare). 15 To confirm the stability of 211 At-AAMT, we compared it with or without ascorbic acid by TLC.…”

Astatine Radiopharmaceuticals: Prospects and Problems

“…For this reason, in most of the astatinated compounds investigated, the astatine is attached to an unactivated aromatic carbon. Attempts to introduce astatine on a vinylic carbon and the synthesis of vinyl-substituted astatinated steroid hormones have been reported [38-40]. …”

“…In the early stages of development, aromatic astato compounds were synthesized by exchange halogenation [41-45] or by electrophilic substitution on unactivated [46] or activated aromatic rings [38, 47, 48]. Recently, a commonly used method for exchange radioiodination using copper catalysts has been adapted for astatination [49].…”

“…Visser et al synthesized astatinated estradiol and cholesterol in a carrier-added form from their mercury precursors [52]. Estradiol derivatives containing 211 At on a vinylic carbon also have been synthesized at a no-carrier-added level from tin precursors [38, 39]. The synthesis of 6-[ 211 At]astatomethyl-19-norcholest-5(10)-en-3β-ol, a potential agent presumed to target adrenal neoplasms, by the crown ether-mediated exchange halogenation has been reported [116].…”