Cationic micellar nanoparticles for DNA and doxorubicin co-delivery

•A new kind of cationic nanoparticles for drugs and gene co-delivery were prepared.•These self-assembling cationic nanoparticles are based on PZLL and PAMAM（PZLL-D3）.•pEGFP-N1 and doxorubicin could be transfer to 293T and Hela cells by these micelle.

Cationic micellar nanoparticles for chemotherapeutic drugs and therapeutic gene co-delivery were prepared based on a poly-(N-ε-carbobenzyloxy-l-lysine) (PZLL) and dendritic polyamidoamine (PAMAM) block copolymer (PZLL-D3). PZLL-D3 was synthesized by a copper-catalyzed azide alkyne cyclization (click) reaction between α-alkyne-PZLL and azide focal point PAMAM dendrons. Its structure was characterized by 1H NMR and FTIR, and its buffering capability was determined by acid–base titration. MTT, agarose gel electrophoresis and flow cytometry studies showed that PZLL-D3 revealed low in vitro cytotoxicity, strong pDNA condensation ability, protection of pDNA against deoxyribonuclease I degradation and high gene transfection efficiency in 293T and HeLa cells. In addition, the micellar nanoparticles delivered pDNA and anticancer drug doxorubicin (DOX) simultaneously and efficiently to tumor cells, and the DOX loaded nanoparticles showed sustained in vitro release at pH = 7.4 and 5.8.