Joint CeNS Colloquium with SFB1032

Title: Multifunctional nanopores for single-molecule studies

Location: Faculty of Physics, Kleiner Physikhörsaal N020 and online via Zoom

Host: Dr. Amelie Heuer-Jungemann, Prof. Tim Liedl, Prof. Ralf Jungmann

Summary:

Nanopore sensors are novel single-molecule technologies increasingly used to answer fundamental questions in biology and employed in next-generation sequencing for molecular diagnostics. In this talk I will present the two types of functional nanopores, namely photonic 2D material nanopores and mechanically-adaptable DNA origami pores. In the first class of nanopores, we employ hexagonal boron nitride (hBN) as solid-state membranes that enable single-molecule DNA homopolymer translocations and discrimination. Additionally, using super-resolution imaging techniques, we investigate the spatial and spectral properties of optically-active defects in hBN membranes and engineer these ultrabright emitters as nanoprobes for fluorescence-based detection of single molecules. We furthermore demonstrate 2D and 1D confined ssDNA diffusion on pristine hBN surfaces via single-molecule localization microscopy, thereby generating a sensing platform that could achieve isolation, sorting and enrichment of biomolecules directly on-chip without the need for complex device design and fabrication. For the second class of nanopores, we combine the structural precision of DNA origami nanotechnology with machine-inspired component design to generate structurally-adaptable nanopores featuring reversible gating triggers. Using AFM, TEM and DNA PAINT we confirm the conformational changes that modulate the size of the nanopore channel. The interactions of the nanopores with lipid bilayers are tested in a cDICE (continuous droplet interface crossing encapsulation) system, where the DNA origami nanoactuators are directly integrated during liposome formation. We confirm localization of the actuators at the membrane via confocal fluorescence imaging, and demonstrate size-selective translocation of Dextran molecules of different molecular weights via dye influx assays.

These nanopore systems advance our understanding of bionanophotonics by enabling the study of the light-matter interactions in confined nanoscale volumes, and open up prospects for massively parallel biomarker detection while retaining single-molecule resolution using wide-field fluorescence microscopy. We also introduce a new class of spatially adaptable nanopores, which can be employed in the delivery of macromolecules, as well as in the development of synthetic cells.

See also CeNS Colloquium website