Self-assembly of Dendrimer-DNA amphiphiles and their catalysis as G-quadruplex/hemin DNAzymes

Nanomaterials self-assembled by DNA amphiphiles have great potential application in catalysis, bioimaging and biomedicine. Here, we constructed two kinds of DNA-dendrimer amphiphiles including the G-quadruplex-dendrimer hybrid (G20-Den) and single-stranded DNA-dendrimer hybrid (D20-Den) as a control. Both of them self-assembled into nanofibers with a length of several micrometers in MES buffer, and the diameter of G20-Den nanofibers was smaller than that of D20-Den nanofibers due to the compact stacking of G-quadruplex formed in G20-Den hybrids. At the same time, the catalytic properties of G20-Den nanofiber/hemin, as horseradish peroxidase-mimicking DNAzymes, were investigated. Our results showed that G20-Den nanofiber/hemin, as well as the single-stranded G20/hemin system, exhibited higher catalytic peroxidation activity than D20-Den nanofiber/hemin. Furthermore, through simple ultrafiltration, the recycle of these nanofibers can be simply achieved. This research has provided a new solution for the construction of functional DNA nanomaterials.