Effects of Quencher Charge

It appears that more positively charged viologens have either greater electron affinity or a stronger electrostatic attraction through which they can bind HPTS in a non-fluorescent quencher/dye complex, or both. That our system operates via static and not dynamic quenching was confirmed with temperature experiments and through absorbance studies, the latter of 

Glucose response of viologens with HPTS (4 x 10 M) at pH 7.4. Optimized quencher-to-dye ratios for m-WSV, /n-BBVMP, and wz-BBVBP with HPTS were, respectively, 31 1 125 1 and 125 1. 

Several additional studies were earried out exploring a wide variety of quenchers based on variously substituted bipyridinium and phenan-throlinium species. Together, with the work described above, these studies demonstrate the considerable versatility possible with respect to the reeep-tor component in this system. In the next section we describe how similar flexibility and versatility can be achieved, with respect to the fluorophore reporters, in our two-eomponent system. 

4 Variations in Fluorescent Reporters-Sulfonamide Derivatives of HPTS 

1 Glucose Sensing Across the Visible Spectrum with and Anionic Fluorescent Etyes 

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