ACS Sensors
ACS Sensors
4 years ago

Single Molecule Nanopore Spectrometry for Peptide Detection

Single Molecule Nanopore Spectrometry for Peptide Detection
Sensing and characterization of water-soluble peptides is of critical importance in a wide variety of bioapplications. Single molecule nanopore spectrometry (SMNS) is based on the idea that one can use biological protein nanopores to resolve different sized molecules down to limits set by the blockade duration and noise. Previous work has shown that this enables discrimination between polyethylene glycol (PEG) molecules that differ by a single monomer unit. This paper describes efforts to extend SMNS to a variety of biologically relevant, water-soluble peptides. We describe the use of Au25(SG)18 clusters, previously shown to improve PEG detection, to increase the on- and off-rate of peptides to the pore. In addition, we study the role that fluctuations play in the single molecule nanopore spectrometry (SMNS) methodology and show that modifying solution conditions to increase peptide flexibility (via pH or chaotropic salt) leads to a nearly 2-fold reduction in the current blockade fluctuations and a corresponding narrowing of the peaks in the blockade distributions. Finally, a model is presented that connects the current blockade depths to the mass of the peptides, which shows that our enhanced SMNS detection improves the mass resolution of the nanopore sensor more than 2-fold for the largest cationic peptides studied.

Publisher URL: http://dx.doi.org/10.1021/acssensors.7b00362

DOI: 10.1021/acssensors.7b00362

You might also like
Discover & Discuss Important Research

Keeping up-to-date with research can feel impossible, with papers being published faster than you'll ever be able to read them. That's where Researcher comes in: we're simplifying discovery and making important discussions happen. With over 19,000 sources, including peer-reviewed journals, preprints, blogs, universities, podcasts and Live events across 10 research areas, you'll never miss what's important to you. It's like social media, but better. Oh, and we should mention - it's free.

  • Download from Google Play
  • Download from App Store
  • Download from AppInChina

Researcher displays publicly available abstracts and doesn’t host any full article content. If the content is open access, we will direct clicks from the abstracts to the publisher website and display the PDF copy on our platform. Clicks to view the full text will be directed to the publisher website, where only users with subscriptions or access through their institution are able to view the full article.