Nanopore analysis of cis-diols in fruits

Abstract

Natural fruits contain a large variety of cis-diols. However, due to the lack of a high-resolution sensor that can simultaneously identify all cis-diols without a need of complex sample pretreatment, direct and rapid analysis of fruits in a hand-held device has never been previously reported. Nanopore, a versatile single molecule sensor, can be specially engineered to perform this task. A hetero-octameric Mycobacterium smegmatis porin A (MspA) nanopore modified with a sole phenylboronic acid (PBA) adapter is prepared. This engineered MspA accurately recognizes 1,2-diphenols, alditols, α-hydroxy acids and saccharides in prune, grape, lemon, different varieties of kiwifruits and commercial juice products. Assisted with a custom machine learning program, an accuracy of 99.3% is reported and the sample pretreatment is significantly simplified. Enantiomers such as DL-malic acids can also be directly identified, enabling sensing of synthetic food additives. Though demonstrated with fruits, these results suggest wide applications of nanopore in food and drug administration uses.

Editors’ Choice—Perspective—Deciphering the Glycan Kryptos by Solid-State Nanopore Single-Molecule Sensing: A Call for Integrated Advancements Across Glyco- and Nanopore Science

“…76 A bottom-up approach for training machine learning used phenylboronic acid labelled protein nanopores to transiently interact with the readily available monomer and disaccharide glycans standards and cis-diol fruit extracts. 69,78,83 Extending this approach to monomers digested from a glycopolymer-or perhaps within an intact glycopolymer-would require appreciable further development, but the approach is nevertheless compelling and contextualizes enabling concepts and approaches. 84 Analytes transiting small nanopores are subject to nanoconfinement and interactions with the nanopore surface.…”

Nanopores Reveal the Stoichiometry of Single Oligoadenylates Produced by Type III CRISPR-Cas

“…As such, the inability of established techniques to detect single messenger molecules prohibits the resolution of rare but decisive species within a majority of other molecules. By contrast, nanopore technology offers the necessary single-molecule resolution to overcome these fundamental limitations, as previously demonstrated. − …”

“…By contrast, nanopore technology offers the necessary single-molecule resolution to overcome these fundamental limitations, as previously demonstrated. 25 − 29 …”