A comparative study of assembly and disassembly process of dimeric and monomeric cyanine dyes with DNA templates

Cyanine dyes have attracted more and more interest due to their controllable assembly and disassembly process with biomolecular templates. The self-assembly of cyanine dye not only depend on the environment, but also on their structures. Here, we report assembly and disassembly of two cyanine dyes, a dimeric cyaine dye (TC-P4) and its corresponding monomer (TC). In PBS, these dyes could form aggregates. The parallel c-myc G-quadruplex as a template causes the transformation of TC-P4 from H-aggregates to dimer and monomer; while duplex and single-stranded DNAs could not. The interaction between these DNAs motifs and TC could all induce the appearance of monomer band. Parallel c-myc G-quadruplex could enhance the fluorescence intensity of TC-P4 and TC. The self-assembly and disassembly of TC and TC-P4 could be regulated and used as probes for G-quadruplex recognition from duplex and single-stranded DNAs in solution.