Pteridines are naturally occurring, highly fluorescent compounds that are structurally similar to purines and that were first isolated from butterfly wings in 1889. The pteridines developed by Hawkins and co-workers are incorporated into DNA through a deoxyribose moiety identical to that of native DNA with no “linker-arm” attachment involved.
Amino-modified oligonucleotides have been routinely employed in solid support and label (or functionality) attachment chemistries. The 5′-terminus of the oligonucleotide is normally the target end for modification because of the ease of incorporation as the last step in automated synthesis.
A disulfide thiol modifier is available for 5′-end modification. A variety of tether lengths holding the thiol moiety can be varied to space the oligonucleotide away at a defined distance.
We also offer 2′- thiol modified oligonucleotides. A reporter molecule or reactive group can be spaced from a probe oligonucleotide through tethers of varying lengths to determine all feasible possibilities for the docking of two or more domains.
We also offer 2′-amino modified oligonucleotides through the use of our SUC/MOX precursor strategy. By using this methodology we can incorporate amino-modifiers internally (currently at pyrimidine nucleosides – C and U analogs) within the oligonucleotide.
Complex probes can be made to suit your assay design. A combination of two or more different fluorescent dyes and other reporter groups can be incorporated on the oligonucleotide. Please contact us for more details, or to request a quote.
Biotin is widely used for DNA/RNA detection/isolation due to the extremely high affinity of the biotin-streptavidin interaction (association constant 1015/M). Biotin moieties can be incorporated within the oligo at any position and multiple times if desired. We have long and super-long tethering arms for improved binding kinetics, increased binding capacity of large DNA fragments, and for accessibility to enzymatic events occurring at the solid-phase surface.
High purity RNA can be synthesized using standard monomers with established 2′-O-TOM protecting groups. Custom RNA has successfully been used in antisense and RNA interference technologies. Furthermore, we can modify the RNA at the 5′- or 3′-ends and within the oligo at the 2′-position of C and U if desired. Please contact us for more details or to request a quote.