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bioRxiv · 10.1101/2024.10.15.618413

Targeted, high-resolution sensing of volatile organic compounds by covalent nanopore detection

Abstract

Volatile organic compounds are choice analytes in a variety of contexts. For example, humans release over 4000 volatile organic compounds, many of which are diagnostic of life-threatening medical conditions. A combination of a large number of potential analytes requires the application of costly, cumbersome technology. Here, we show that covalent nanopore sensing can be used for the targeted detection of a reduced set of analytes in a mixture: in this case aldehydes, which constitute [~]5% of human volatiles. Further, nanopore engineering permits high-resolution detection, which allows closely related aldehydes including isomers to be distinguished. Differential sensing of other chemical classes, such as alcohols, is demonstrated by leveraging their enzymatic conversion to aldehydes. Our approach is compatible with the use of cheap, portable, user-friendly diagnostic devices applicable to a wide variety of objectives, including pollutant monitoring, food and beverage testing and the quality control of pharmaceuticals, as well as disease diagnostics.

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McGivern, L. E., Lim, Z. H., Yuan, Y., Bo, Z., Bayley, H., Qing, Y.. 2024-10-18. Targeted, high-resolution sensing of volatile organic compounds by covalent nanopore detection. https://doi.org/10.1101/2024.10.15.618413

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