Trading polymeric microspheres: exchanging DNA molecules via microsphere interaction

Colloids Surf B Biointerfaces. 2015 Apr 1;128:94-99. doi: 10.1016/j.colsurfb.2015.02.014. Epub 2015 Feb 17.


A new class of artificial molecular transport system is constructed by polymeric microspheres. The microspheres are prepared by self-assembly of poly(ethylene glycol)-block-poly(3-dimethyl(methacryloyloxyethyl)ammonium propane sulfonate), PEG-b-PDMAPS, by intermolecular dipole-dipole interaction of sulfobetaine side chains in water. Below the upper critical solution temperature (UCST) of PEG-b-PDMAPS, the microspheres (∼1μm) interact with other microspheres by partial and transit fusion. In order to apply the interaction between microspheres, a 3'-TAMRA-labeled single-stranded DNA oligomer (ssDNA) is encapsulated into a PEG-b-PDMAPS microsphere by thermal treatment. The exchange of ssDNA between microspheres is confirmed by fluorescence resonance energy transfer (FRET) quenching derived from double-stranded formation with complementary 5'-BHQ-2-labeled ssDNA encapsulated in PEG-b-PDMAPS microspheres. The exchange rate of ssDNA is controllable by tuning the composition of the polymer. The contact-dependent transport of molecules can be applied in the areas of microreactors, sensor devices, etc.

Keywords: Double strand formation; Microspheres; Self-assembly; Single-stranded DNA oligomer; Zwitterionic block copolymers.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • DNA Probes / chemistry*
  • DNA, Single-Stranded / chemistry*
  • Drug Compounding
  • Facilitated Diffusion
  • Fluorescence Resonance Energy Transfer
  • Hot Temperature
  • Methacrylates / chemistry*
  • Microspheres
  • Polyethylene Glycols / chemistry*
  • Quaternary Ammonium Compounds / chemistry*
  • Temperature
  • Thermodynamics
  • Water


  • 3-dimethyl(methacryloyloxyethyl)ammonium propane sulfonate
  • DNA Probes
  • DNA, Single-Stranded
  • Methacrylates
  • Quaternary Ammonium Compounds
  • Water
  • Polyethylene Glycols