No-carrier-added meta-[123I]iodobenzylguanidine: synthesis and preliminary evaluation.
No-carrier-added [123I]MIBG was prepared from 3-(trimethylsilyl)benzylguanidine in 80-90% yield. Binding of this tracer to SK-N-SH human neuroblastoma cells maintained a constant level of > 50% over 2-3 log activity range. In comparison, the binding of [123I]MIBG prepared by isotopic exchange steadily decreased with dose. Biodistribution studies in normal mice demonstrated maximal concentrations in heart and adrenals for both preparations. In heart, significant 1.5-3.0 times higher levels (P < 0.05) were seen for the no-carrier-added preparation. Radiation dosimetry calculations suggest that the no-carrier-added preparation would increase the dose received by several tissues, most notably the heart where a 91% increase in dose is predicted.
Vaidyanathan
G
G
Department of Radiology, Duke University Medical Center, Durham, NC 27710, USA.
Zalutsky
M R
MR
D019797:3-Iodobenzylguanidine; D000818:Animals; D000970:Antineoplastic Agents / Q000138:chemical synthesis*; D002460:Cell Line; D006801:Humans; D007457:Iodine Radioisotopes; D007462:Iodobenzenes / Q000138:chemical synthesis* / Q000493:pharmacokinetics; D051379:Mice; D008807:Mice, Inbred BALB C; D011829:Radiation Dosage; D014018:Tissue Distribution; D014407:Tumor Cells, Cultured
D000970:Antineoplastic Agents; D007457:Iodine Radioisotopes; D007462:Iodobenzenes; D019797:3-Iodobenzylguanidine