Scanning electrochemical probe microscopies (SEPMs) have played a key role in advancing small-scale electrochemistry. SEPMs use an electrochemical probe (micro/nanoelectrode or pipet) to quantify and map local interfacial fluxes of electroactive species and have found increasingly wide applications. Our contribution to the Fundamental and Applied Reviews in Analytical Chemistry 2019 discussed how advances in SEPMs converged towards nanoscale electrochemical mapping. This inflection in experimental capability has opened up myriad opportunities for SEPMs in many types of systems, from material and energy sciences to the life sciences. The enhancement in the spatial resolution of imaging techniques, and instrumental developments, have resulted in significant increases in the size of electrochemical datasets from a typical experiment and served to speed up measurement throughput. Next generation nanoelectrochemistry will thus see an emphasis on “big data”, its analysis, storage and curation, high throughput analysis and parallelization, “intelligent” instruments and experiments, active control of nanoscale systems, and the integration of nanoelectrochemistry and nanoscale micro(spectro)scopy. For this review article, we focus on recent advances in frontier nanoscale electrochemistry, analysis and imaging techniques that are already addressing some of these key targets, and are well-placed to embrace other aspects in the near future. Our goal is to provide an overview of the present state-of-the-art in high throughput nanoelectrochemistry and imaging, and signpost promising new avenues for nanoscale electrochemical methods.
DNA nanotechnology has paved the way for new generations of programmable nanomaterials. Utilising the DNA origami technique, various DNA constructs can be designed, ranging from single tiles to the self-assembly of large-scale complex multi-tile arrays. These DNA nanostructures have enabled new applications in biosensing, drug delivery and other multifunctional materials. In this study, we demonstrate real-time, non-destructive and label-free fingerprinting of higher-order assemblies of DNA origami nanostructures using solid-state nanopores. Using this approach, we quantify the assembly yields for each DNA origami nanostructure with single-entity resolution using the nanostructure-induced charge introduced in the nanopore as a discriminant. We compare the assembly yield of the supramolecular DNA nanostructures obtained with the nanopore with agarose gel electrophoresis and AFM imaging and demonstrate that the nanopore system can provide enhanced information about the nanostructures. We envision that this nanopore detection platform can be applied to a range of nanomaterial designs and enable the analysis and manipulation of large DNA assemblies in real-time with single-molecule resolution.STATEMENT OF SIGNIFICANCEWe demonstrate a single molecule high-throughput approach for the analysis of higher-order DNA origami assemblies with a crowded nanopore. The technique enables the characterisation of DNA origami nanostructures at statistically relevant numbers in real-time and at single-molecule resolution while being non-destructive and label-free, and without the requirement of lengthy sample preparations or use of expensive reagents. We exemplify the technique by demonstrating the quantification of the assembly yield of DNA origami nanostructures based on their equivalent charge surplus computed from the ion current signals recorded. Compared to the standard analysis methods of AFM and agarose gel electrophoresis, the nanopore measurements provides enhanced information about the nanostructures.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.