Construction of novel multifunctional luminescent nanoparticles based on DNA bridging and their inhibitory effect on tumor growth†
Cyclic RGD peptide was introduced onto the surface of silver nanoparticle (AgNP)-single strand DNA (ssDNA)-graphene quantum dots (GQDs) (ADG) after coating with a hybrid phospholipid material (ADG-DDPC) to be used for antitumor treatment. The Ag and ssDNA content was quantified. The morphology and properties of the nanoparticles were characterized by ultraviolet-visible absorption spectroscopy (UV-VIS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and atomic force microscopy (AFM). The etching effect of H2O2 on the AgNPs and the cleavage of DNA was observed. The cytotoxicity of the ADG-DDPC was investigated using the cell viability and LDH content. The cell uptake was evaluated by using the fluorescence recovery of the GQDs in the ADG-DDPC. The antitumor effects of ADG-DDPC were also evaluated. The content of the ssDNA was 15.3 μg mL−1. The content of the silver element in AgNPs was 3.75 μg mL−1 and 20.43 μg mL−1 in ADG-DDPC. ADG were distributed uniformly with the GQDs on the surface. After coating with hybrid phospholipid membranes containing DSPE-PEG2000-cRGD, ADG-DDPC was detected with an average size of 25.2 nm with a low IC50 of 209.68 ng mL−1 and showed LDH activity on HeLa cells. A better cellular uptake of ADG-DDPC was observed in HeLa cells, compared with cRGD-unmodified ADG nanoparticles (ADG-DDP), up to 6 and 12 h using the fluorescence recovery of GQDs as a measurement. Compared with ADG-DDP (3.6 mg of silver equivalent per kg body weight), ADG-DDPC at the same dose significantly halted 50.9% of tumor growth with little change to body weights when compared with a PTX Injection (10 mg kg−1). The novel nanoparticles, ADG-DDPC, could target tumor sites to exhibit multifunctional inhibition on tumor growth with little toxicity.