Bell's group uses DNA nanotechnology and advanced optical microscopy for single-molecule biosensing. Research directions: (1) DNA-based biosensing — DNA origami structures as programmable biosensing platforms; using structural switching of DNA nanodevices to sense specific biomolecules with single-molecule sensitivity; (2) Super-resolution microscopy with DNA — DNA-PAINT and FRET-based single-molecule localization for mapping molecular architectures in cells; (3) Solid-state nanopores — DNA-threaded through nanopores as a precision biosensor for protein identification and force measurement; (4) Multiplexed single-molecule detection — combining DNA-based sensors with optical readout for parallel biomolecule profiling. New group established at UCL, strong biosensing focus.