Closo-dodecaborate(2-) as a linker for iodination of macromolecules: Aspects on conjugation chemistry and biodistribution
1999 (English)In: Bioconjugate chemistry, ISSN 1043-1802, Vol. 10, no 3, 338-45 p.Article in journal (Refereed) Published
Boron-containing compounds like closo-dodecaborate(2-) are in theory suitable for radioactive labeling with halogens. The boron-halogen bond is stronger than carbon-halogen bond and is not likely to be recognized by deiodinating enzymes in vivo. Peptides and proteins may be conjugated with various closo-dodecaborate(2-)-containing ligands, and thereafter, the conjugate can be iodinated. Since closo-dodecaborate(2-) is more avidly iodinated than tyrosine in moderately acidic media, such conjugates may be directly labeled on the boron part with radioisotopes of iodine using the standard Chloramine-T procedure. Mercapto-undecahydro-closo-dodecaborate(2-) (BSH) was reacted with the double bond of allyldextran to form a boronated dextran compound of the molecular size of about 70 kDa. This compound, in the text denoted as Dx-BS, and cesium dodecahydro-closo-dodecaborate(2-) were labeled using iodine-125. The two compounds were administered to rats in order to study their in vivo stability. The results indicate that iodinated Dx-BS is stable for about 20 h in vivo. The degradation rate, as indicated by thyroid uptake, was found low. [125I]Iodo-closo-dodecaborate(2-), which is a possible degradation product of [125I]Dx-BS-I, was rapidly excreted in urine without significant accumulation in any organ.
Place, publisher, year, edition, pages
1999. Vol. 10, no 3, 338-45 p.
Medical and Health Sciences
IdentifiersURN: urn:nbn:se:uu:diva-57199DOI: 10.1021/bc980033sPubMedID: 10346862OAI: oai:DiVA.org:uu-57199DiVA: diva2:85108