Colorimetric chiral discrimination of lysine enantiomers and configurable logic gate operation based on fluorescein-functionalized polydiacetylene vesicles

Abstract

The chiral recognition of amino acid enantiomers is of great significance owing to the fact that L-type amino acids act as the basic chiral elements of the molecular architecture of proteins. In this study, a novel and simple colorimetric chiral sensor based on fluorescein-substituted polydiacetylene (FPDA) vesicles was developed. Due to their different complexing abilities with Cu²⁺ ions, FPDA vesicles and lysine enantiomers, the above hybrid PDA vesicle sensors allow practical chiral discrimination of lysine. Moreover, with two defined stimulus conditions from each of the parameters pH, Cu²⁺ ion, D- or L-lysine, the hybrid FPDA vesicles were used to construct two basic “AND” and “OR” logic operations successfully. These logic gate operations, which are based on colorimetric conjugated polymers and can discriminate chiral enantiomers, may provide new opportunities for chiral sensing and information storage in complicated microenvironments.