Tuning DNA Binding Kinetics in an Optical Trap

15.07.2013

Our Letter on the “Tuning DNA binding kinetics in an optical trap by plasmonic nanoparticle heating” is published in NanoLetters. In this work, we demonstrate a novel application of optically trapped plasmonic nanoparticles. We show that plasmonic heating of individual nanoparticle dimers in an optical trap enables the tuning of the hybridization kinetics of complementary DNA molecules attached to the nanoparticles. DNA hybridization events are detected optically by the change in the plasmon resonance frequency due to plasmonic coupling of the nanoparticles. We find that at larger trapping powers (i.e. larger temperatures and stiffer traps), the hybridization of complementary DNA strands slows down. This effect is the result of higher temperatures preventing the formation of dimers with lower binding energies. Our results demonstrate that plasmonic heating can be used to fine-tune the kinetics of biomolecular binding events.