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PubMed · 10556882

The ion channel switch biosensor.

G Woodhouse·L King·L Wieczorek·P Osman·B Cornell
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Abstract

A biosensor technology is described which provides a direct measurement for functional molecular interactions, at the surface of a tethered bilayer membrane, through the electrical transduction of chemically modified ion-channels. High sensitivity of analyte detection is achieved due to the large flux of ions transmitted through the ion channel. The biomimetic sensor surface allows the molecular recognition to be measured in complex biological matrices (such as blood and sera) without compromising sensitivity. We have used the sensor for activity and concentration measurements for a range of analytes, which include bacteria, DNA, proteins and drugs. We have a quantitative model for the biosensor performance which is described by three-dimensional molecular interactions with the membrane surface and two-dimensional molecular interactions within the tethered bilayer.

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Biosensing TechniquesDigoxinGramicidinImmunoglobulin Fab FragmentsIon ChannelsLipid BilayersJournal ArticleResearch Support, Non-U.S. Gov't

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G Woodhouse, L King, L Wieczorek, P Osman, B Cornell. The ion channel switch biosensor.. https://doi.org/10.1002/(sici)1099-1352(199909%2F10)12%3A5%3C328%3A%3Aaid-jmr474%3E3.0.co%3B2-5

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