Glutathione-mediated release of functional plasmid DNA from positively charged quantum dots.
DNA was efficiently bound to water-soluble positively charged CdTe quantum dots (QDs) through complementary electrostatic interaction. These QDs-DNA complexes were disrupted and DNA was released by glutathione (GSH) at intracellular concentrations. Interestingly, there was almost no detectable DNA released by extracellular concentration of GSH. The formation of QDs-DNA complexes and GSH-mediated DNA release from the complexes were confirmed by dye displacement assay, electrophoretic mobility shift assay (EMSA), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) experiments. The released DNA retained transcriptional activity and expressed enhanced green fluorescent protein (EGFP) after being transfected into HEK 293 cells. The transfection efficiency measured by flow cytometry (FCM) was comparable with the positive control. The obvious difference of GSH concentration in nature between the intra- and extracellular environments as well as the GSH concentration-dependent triggered release suggests potential applications of these positively QDs in selective unpacking of payload in living cells in a visible manner.
Li
Dan
D
State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 5625 Renmin Street, Changchun, Jilin 130022, PR China.
Li
Gaiping
G
Guo
Weiwei
W
Li
Peicai
P
Wang
Erkang
E
Wang
Jin
J
D002460:Cell Line; D004247:DNA / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D024202:Electrophoretic Mobility Shift Assay; D005978:Glutathione / Q000737:chemistry* / Q000378:metabolism; D006801:Humans; D046529:Microscopy, Electron, Transmission; D008962:Models, Theoretical; D010957:Plasmids / Q000235:genetics*; D045663:Quantum Dots
D004247:DNA; D005978:Glutathione