Check out this paper in the American Chemical Society’s ACS Nano journal, resulting from Fabio Marcuccio’s current virtual secondment with The Edwards Lab at the University of Arkansas. It’s a fascinating insight into the better salts for enhancing signal outputs in nanopores.
Nanopore systems have emerged as a leading platform for the analysis of biomolecular complexes with single-molecule resolution. The conformation of biomolecules, such as RNA, is highly dependent on the electrolyte composition, but solid-state nanopore systems often require high salt concentration to operate, precluding analysis of macromolecular conformations under physiologically relevant conditions. Here, Fabio reports the implementation of a polymer–electrolyte solid-state nanopore system based on alkali metal halide salts dissolved in 50% w/v poly(ethylene) glycol (PEG) to augment the performance of our system. He and his co-authors show that polymer–electrolyte bath governs the translocation dynamics of the analyte which correlates with the physical properties of the salt used in the bath. This allowed them to identify CsBr as the optimal salt to complement PEG to generate the largest signal enhancement. Harnessing the effects of the polymer–electrolyte, they probed the conformations of the Chikungunya virus (CHIKV) RNA genome fragments under physiologically relevant conditions. Their system was able to fingerprint CHIKV RNA fragments ranging from ∼300 to ∼2000 nt length and subsequently distinguish conformations between the co-transcriptionally folded and the natively refolded ∼2000 nt CHIKV RNA.
Fabio expects that the polymer–electrolyte solid-state nanopore system will further enable structural and conformational analyses of individual biomolecules under physiologically relevant conditions.
A great development from your ongoing virtual secondment, Fabio!