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Threshold detection using indicator-displacement assays: an application in the analysis of malate in Pinot Noir
Anna M Piatek1, Yannick J Bomble, Sheryl L Wiskur
1Department of Chemistry and Biochemistry, The University of Texas, 1 University Station, A5300, Austin, Texas 78712, USA.
Abstract:
The mathematics for modeling indicator-displacement assay isotherms is presented and contrasted to the classical host-guest binding isotherm. It is shown that the signal response can be tuned to occur closer to 1 equiv of guest relative to a standard binding algorithm. This delay in response leads to a better triggering protocol for threshold detection schemes. The determination of malate in Pinot Noir must was calculated using this new mathematical model, which demonstrates how a color change can be tuned to occur near a desired concentration of analyte.
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