Ingersoll, Christine M. Jordan, Jeffrey D. Bright, Frank V. Accessibility of the Fluorescent Reporter Group in Native, Silica-Adsorbed, and Covalently Attached Acrylodan-Labeled Serum Albumins Fluorescence quenching techniques are used to investigate the accessibility of a model biorecognition element−reporter group system when in buffer, surface-adsorbed, and covalently attached to a silica surface. The site-selective fluorescent reporter group, 6-acryloyl(dimethylamino)naphthalene (acrylodan, Ac), is attached covalently (at cysteine-34) to bovine and human serum albumin (BSA and HSA, respectively) and serves as a surrogate recognition element−reporter group system. Molecular oxygen is used to quench the Ac fluorescence and the accessibility, in the form of bimolecular rate constants (<i>k</i><sub>q</sub>), in each model system is quantified. Although one might expect these systems to exhibit similar behavior, differences in quenching characteristics are observed, such as wavelength dependency of the Stern−Volmer quenching constant (<i>K</i><sub>SV</sub>) for the native proteins in buffer. BSA-Ac exhibits wavelength dependent <i>K</i><sub>SV</sub> values as well as a blue-shifted emission spectrum on O<sub>2</sub> addition. Physisorption of BSA-Ac onto a fused-silica optical fiber <i>lowers</i> the accessibility of Ac to O<sub>2</sub>, whereas covalent attachment of BSA-Ac to APTES/glutaraldehyde-modified silica <i>enhances</i> the accessibility of the Ac reporter group to O<sub>2</sub>. HSA;Ac reporter group;APTES;wavelength;quenching;Fluorescent Reporter Group;BSA;O 2 addition;O 2;covalently;K SV values;exhibit;accessibility;model 1996-09-15
    https://acs.figshare.com/articles/journal_contribution/Accessibility_of_the_Fluorescent_Reporter_Group_in_Native_Silica-Adsorbed_and_Covalently_Attached_Acrylodan-Labeled_Serum_Albumins/3583356
10.1021/ac960315q.s001