Ammonium and guanidinium dendron–carbon nanotubes by amidation and click chemistry and their use for siRNA delivery

In this work we describe a series of multi-walled carbon nanotube (MWCNT) conjugates, functionalized with different dendrons bearing positive charges at their termini (i.e. ammonium or guanidinium groups). The dendrimeric units have been anchored to the nanotube scaffolds using two orthogonal synthetic approaches, such as amidation and click reactions. The final nanohybrids were characterized by complementary analytical techniques while their ability to interact with siRNA has been investigated by means of agarose gel electrophoresis. The demonstration of the cell uptake capacity, the low cytotoxicity and the ability of these cationic conjugates to silence cytotoxic genes render them promising carriers for genetic material.