کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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6836 | 520 | 2012 | 10 صفحه PDF | دانلود رایگان |
Polyethylenimine (PEI) functionalized carbon dots (CD-PEI) were fabricated by one-step microwave assisted pyrolysis of glycerol and branched PEI25k mixture where the formation of carbon nanoparticles and the surface passivation were accomplished simultaneously. In this hybrid C-dot, PEI molecule played two key roles in the system − as a nitrogen-rich compound to passivate surface to enhance the fluorescence and as a polyelectrolyte to condense DNA. This CD-PEI was shown to be water soluble and emit stable bright multicolor fluorescence relying on excitation wavelength. The DNA condensation capability and cytotoxicity of CD-PEI could be regulated by pyrolysis time possibly due to the somewhat destruction of PEI during the formation of carbon dots. CD-PEI obtained at an appropriate pyrolysis time exhibited lower toxicity, higher or comparable gene expression of plasmid DNA in COS-7 cells and HepG2 cells relative to control PEI25k. Intriguingly, the CD-PEIs internalized into cells displayed tunable fluorescent emission under varying excitation wavelength, suggesting the potential application of CD-PEI in gene delivery and bioimaging.
Journal: Biomaterials - Volume 33, Issue 13, May 2012, Pages 3604–3613