With Thiol-C3 (Figure 1), a 3-carbon spacer arm separates the Thiol moiety and the oligonucleotide, thereby reducing steric interactions between the Thiol and the oligo itself. metabion offers Thiol-C3 in its standard DNA portfolio and the Thiol-C3 modified oligos will be supplied as disulfides. Customer should reduce the disulfide bonds by using TCEP, DTT or other reducing agents to generate a reduced thiol group. For a short protocol, please visit our download section.
Figure 1. Structure of Thiol-C3 (R = sequence).