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In recent years, various anti-tumor treatment methods have emerged in endlessly. Here in, a novel anti-tumor mechanism is designed and a special double-layer nanoparticles (CMC/MgO @ FA-CS/BODIPY NPs) were prepared. It utilizes the special acidic environment of cell lysosomes to swell violently in lysosomes, destroy lysosomes and release hydrolases. Because the number of tumor cell lysosomes is significantly more than that of normal cells, and the volume is also larger, resulting in the release of a large number of hydrolases to digest the entire tumor cell and cause it to die, while the number of normal cell lysosomes is small, and the destruction of lysosomes is not enough to kill cell. In this paper, animal experiments and the control experiments of tumor cells and normal cells prove that the designed nanoparticles have a broad-spectrum antineoplastic activities and are harmless to normal cells. At the same time, the nanoparticles are mainly composed of carboxymethyl cellulose (CMC), chitosan (CS) and other commonly used pharmaceutical excipients, which have no toxicity. Therefore, this method is a new safe and effective way to treat tumors. It has not been reported in any literature.

Polycations as one of non-viral vectors have gained increasing attentions. In this paper, polyethylenimine(PEI)-grafted polycarbonates (PMAC-g-PEIx) were synthesized as a kind of biodegradable polycations for gene delivery. Backbone polymer, poly(5-methyl-5-allyloxycarbonyl-trimethylene carbonate) (PMAC), was synthesized in bulk catalyzed by immobilized porcine pancreas lipase (IPPL). Then, PMAC-O, the allyl epoxidation product of PMAC, was further modified by PEIx with low molecular weight (x = 423, 800 and 1800). The MWs of PMAC-g-PEIx, measured by GPC-MALLS, were 81,900, 179,900 and 200,600 g/mol with polydispersities of 1.2, 1.4 and 1.7, respectively. PMAC-g-PEIx could form positively charged nano-sized particles (30-90 nm) with pDNA, and all the three PAMC-g-PEIx/DNA polyplexes had similar buffer capabilities. In vitro experiments demonstrated that the PAMC-g-PEIx showed much low cytotoxicity and enhanced transfection efficiency could be found in comparison with PEI25K in 293T cells. Furthermore, pre-incubation of PMAC-g-PEI1800 showed a weakening binding capacity with DNA. The biodegradability of PMAC-g-PEIx can facilitate the efficient release of pDNA from polyplexes and reduce cell cytotoxicity. These results suggested that PMAC-g-PEIx would be a promising non-viral biodegradable vector for gene delivery system.