Labelling Oligonucleotides with Imagable Radionuclides

Abstract

Oligonucleotides are relatively short polymers of either ribonucleic (RNA) or deoxyribonucleic (DNA) acids joined in a linear fashion through their phosphate-sugar backbone. In the single-stranded oligonucleotide, the nucleotides within are arranged in space in such a manner that their bases are uniquely positioned to bind via hydrogen bonds to complementary bases on a second single-stranded oligonucleotide. One of the purine bases will bind with a pyrimidine base, adenine with thymidine (or uracil in RNA) and guanine with cytosine. The process by which a double-stranded oligonucleotide is formed by the “zippering” of two complementary single-stranded oligonucleotides by Watson-Crick base pairing can be termed hybridization [1]. It is this property of hybridization, unique to RNA and DNA (if artificial oligomers are excluded), which is likely to render in the near future radiolabeled oligonucleotides useful as radiopharmaceuticals.