Super-resolution imaging with nanopipettes

Uncovering structural information of biological systems at the nanoscale is vital for understanding their dynamics and function. Nanoscale imaging techniques that obtain structural information down to the single-molecule level under physiologically relevant conditions and without affecting the fragile structure of biomaterials are limited. Thus, the realization of such techniques is highly attractive, especially within the biological sciences. Nanopipette-based imaging using scanning ion conductance microscopy (SICM) fulfills these requirements, but resolution limitations and artefact formation hinder obtaining accurate structural information on the scale comparable to the pipette tip. Here, we present a novel technique, super-resolution SICM (SR-SICM), based on image deconvolution using simulated pipette point-spread functions. The technique is demonstrated on different types of nanostructures, where it surpasses the lateral resolution limit of SICM and mitigates imaging artefacts considerably. SR-SICM is applicable to any SICM dataset through user-friendly downloadable software promoting the possibility of single-molecule studies on a routine basis.