Uptake and intracellular fate of multifunctional nanoparticles: a comparison between lipoplexes and polyplexes via quantum dot mediated Förster resonance energy transfer.


Journal Article

Lipoplexes and polyplexes represent the two major nanocarrier systems for nucleic acid delivery. Previous studies examining their uptake and intracellular unpacking rely on organic fluorophores fraught with low signal intensity and photobleaching. In this work quantum dot mediated Förster resonance energy transfer (QD-FRET) was first used to study and compare the cellular uptake and the intracellular fate of oligodeoxynucelotide (ODN)-based lipoplexes and polyplexes. QD605-amine and Cy5-labeled ODN (Cy5-GTI2040) were chosen as the FRET pair. By adjusting the lipid/ODN ratio of lipoplexes and the nitrogen/phosphate (N/P) ratio of polyplexes, lipoplexes and polyplexes with comparable physical properties were produced. The biological activities of dual-labeled lipoplexes and polyplexes remained unaltered compared to their unlabeled counterparts as evidenced by their comparable antisense activities against protein R2 in KB cells. Flow cytometry and confocal microscopy revealed similar pattern of uptake for these two types of nanoparticles, although polyplexes had a higher dissociation rate than lipoplexes in KB cells. We demonstrate that QD-FRET is a sensitive tool to study the uptake and intracellular unpacking of lipoplexes and polyplexes, which may help optimize their formulations for various theranostics applications.

Full Text

Cited Authors

  • Wu, Y; Ho, Y-P; Mao, Y; Wang, X; Yu, B; Leong, KW; Lee, LJ

Published Date

  • October 2011

Published In

Volume / Issue

  • 8 / 5

Start / End Page

  • 1662 - 1668

PubMed ID

  • 21740056

Pubmed Central ID

  • 21740056

Electronic International Standard Serial Number (EISSN)

  • 1543-8392

International Standard Serial Number (ISSN)

  • 1543-8384

Digital Object Identifier (DOI)

  • 10.1021/mp100466m


  • eng