Using Nucleobase Pairing as Supermolecule Linker to Assemble the Bionic Copolymer Nanoparticles with Small Size

The specificity hydrogen bonds of nucleobase pairs are the main linker in DNA and RNA. Compared with conventional covalent-linking polymer to prepare nanoparticles (NPs), nucleobase pairs as supermolecule linker to assemble the bionic copolymer NPs may be an innovative way. Adenine (A) modified poly(e-caprolactone) and thymine (T) modified poly(ethylene glycol) are prepared to assemble multiple hydrogen bonds linked NPs in situ. The introduction of multiple hydrogen bonds into NPs results in a unique method to prepare NPs replacing the conventional assemble method. These NPs exhibit narrow size distribution with the average diameter of 45 nm under pH 7.4. The chemical shift of T NH proton moves from 11.30 to 11.05 ppm with increasing temperature from 25 to 80 °C, and the same phenomenon also appears in A NH2 proton resonance, which demonstrate the existence of hydrogen bonds. The low cytotoxicity of NPs is confirmed by MTT assay using MCF7 tumor cells. Collectively, the novel method opens the possibilities to combine bionics in assembling small size nanoparticles.