Linkers leaving group stability

By using a multistep procedure, DNA molecules have been covalently attached to SWNTs. First, the purified SWNTs were oxidized to form carboxylic acid groups at the ends and sidewalls, followed by reaction with thionyl chloride and ethylenediamine to produce amine-terminated sites. The amines were then reacted with the heterobifunctional cross-linker succinimi-dyl 4-(iV-maleimidomethyl)cyclohexane-l-carboxylate (SMCC), leaving the surface terminated with maleimide groups. Finally, thiol-terminated DNA reacted with these groups to produce DNA-modified SWNTs [161]. AAHien DNA is covalently attached to SWNTs, a better stability, accessibility and selectivity are expected during competitive hybridization. 

---