On demand delivery and analysis of single molecules on a programmable nanopore-optofluidic device.

Nanopore-based single nanoparticle detection has recently emerged as a vibrant research field with numerous high-impact applications. Here, we introduce a programmable optofluidic chip for nanopore-based particle analysis: feedback-controlled selective delivery of a desired number of biomolecules and integration of optical detection techniques on nanopore-selected particles. We demonstrate the feedback-controlled introduction of individual biomolecules, including 70S ribosomes, DNAs and proteins into a fluidic channel where the voltage across the nanopore is turned off after a user-defined number of single molecular insertions. Delivery rates of hundreds/min with programmable off-times of the pore are demonstrated using individual 70S ribosomes. We then use real-time analysis of the translocation signal for selective voltage gating of specific particles from a mixture, enabling selection of DNAs from a DNA-ribosome mixture. Furthermore, we report optical detection of nanopore-selected DNA molecules. These capabilities point the way towards a powerful research tool for high-throughput single-molecule analysis on a chip.

Optical trapping assisted detection rate enhancement of single molecules on a nanopore optofluidic chip.

We use optical trapping to deliver molecular targets to the vicinity of a nanopore for high-throughput single molecule analysis on an optofluidic chip. DNA detection rates increase over 80× to enable detection at attomolar concentrations.