Abstract: A modified nucleoside analogue having the formula (I): P-S-B-L-R where: P is a 5? triphosphate or analogue or derivative thereof; S is a substituted or unsubstituted five- or six-membered sugar, sugar analogue or acyclo sugar analogue, but excluding a dideoxy-sugar, B is a substituted or unsubstituted nitrogenous base or base analogue or derivative thereof; L is a linker group; and R is a substituted or unsubstituted metallocene moiety or substituted or unsubstituted metal complex or substituted or unsubstituted redox-active organic moiety. The modified nucleoside is capable of enzymatic incorporation into a nucleotide chain and allows for redox labelling of nucleotides.

Abstract: The present invention relates to: An aptamer comprising a circular oligonucleotide defining one to four target binding regions; An aptamer comprising an oligonucleotide defining two, three or four thrombin binding quadruplex regions separated by at least partially duplex regions, wherein the quadruplex regions comprise a GGTMGGXGGTTGG sequence wherein M represents A or T and X represents a sequence of two to five nucleotides and/or nucleotide analogues; An aptamer represented by formula (I): 5?D1, wQxD1D2yQzD2,3?—the variables are as defined in the specification; and Aptamers selected from specific sequences.