Figure 5.
The TdT reaction in TB buffer for terminal and internal modification of ODNs. To confirm the functionality, (A) oxanine, (B) biotin, (C) aminoallyl or (D) N6-propargyl group–modified ODNs were reacted each with poly-l-lysine, streptavidin, N-hydroxysuccinimide (NHS)-labeled Cy5 dye, or azide-labeled Cy5 dye, respectively. Denaturing PAGE in a 12% gel (with 7 M urea) with detection of FAM dye (excitation 495 nm, emission 520 nm) was mainly used to visualize the reaction products (adducts) ranging from 20 to 40 nt. a Residual NHS-Cy5 dye. b Artifacts present in the NHS-Cy5 solution.