Sugar-Substituted Poly(p-phenyleneethynylene)s : Sensitivity Enhancement toward Lectins and Bacteria

The synthesis of two novel, water-soluble, sugar-substituted poly(p-phenyleneethynylene)s and their interactions with concanavalin A (Con A) and bacteria (Escherichia coli) are reported, and the issue of sensitivity enhancement is investigated. Both sugar-substituted PPEs (P5 and P7) exhibited strong interactions with Con A with K SV values exceeding 10 8 M -1 . The binding constants between the sugar-substituted polymers and Con A were also quantitatively calculated using isothermal titration calorimetry (ITC) resulting in association constants as high as 10 6 M -1 . P5 and P7 strongly interact with mannose-binding E. coli, which led to their aggregation.