Attachment of cyclodextrin acids to PEGA resin and study of binding with fluorescence microscopy.

Three different cyclodextrin acids, 6,6-di-O-(prop-2-carboxy-1,3-dienyl)-α-cyclodextrin (1), 6-deoxy-β-cyclodextrin-6-carboxylic acid (2), 6-deoxy-β-cyclodextrin-6-ethylenecarboxylic acid (3), were prepared and attached to amino PEGA resin as amides using coupling conditions with COMU and NEM. Host-guest binding to the resins was studied by fluorescence microscopy using 8-anilinoaphtalene-1-sulfonic acid (ANS) as guest, and was found to follow the equation I = I*[ANS]/([ANS] + K) where F, F and K are the fluorescence, maximum fluorescence and K the dissociation constant for the ANS-cyclodextrin complex, respectively. K was 4.