Conjugated polymer-enhanced enantioselectivity in fluorescent sensing

A new strategy to use conjugated polymers to conduct fluorescent enhancement sensing has been developed. Chiral 1,1′-bi-2-naphthol-based binding sites are linked by p-phenylene units to construct a conjugated polymer whose fluorescence is quenched by the aldehyde groups introduced at each binding site. Interaction of this polymer with chiral amino alcohols in the presence of Zn(ii) leads to highly enantioselective fluorescent enhancement. It is found that the chiral conjugated polymer shows greatly enhanced enantioselectivity over the corresponding small molecular sensor under the same conditions. This work provides the first example that a conjugated polymer is used to greatly increase the enantioselectivity of a small molecular sensor in chiral recognition. Simultaneous determination of the concentration and enantiomeric composition of chiral substrates by a fluorescent measurement has been achieved by combining the polymer with salicylaldehyde in the assay.