A π-Extended AIE Platform for Pattern Recognition of Glycosaminoglycans

Accurate discrimination of complicated glycosaminoglycans is a challenging but meaningful task for ensuring their safe use in clinics. With the purpose of reducing the production cost of sensor arrays for glycosaminoglycans, three fluorescence turn-on sensors named TPPEBA, TPPEMe, and TPPEC7 were readily synthesized by simple alkylation of the pyridyl units of the π-extended AIEgen, namely, tetra-(4-pyridylphenyl) ethylene. The designed sensors are cross-reactive toward tested glycosaminoglycans including heparin, chondroitin sulfate, hyaluronic acid, and dextran sulfate, whose mechanism could be ascribed to the multivalent electrostatic, CH···π, and hydrophobic interactions between the sensors and different glycosaminoglycans to form corresponding fluorescent aggregates. The afforded three-component sensor array TPPE-SA is powerful for discrimination of tested glycosaminoglycans in a wide concentration range of 1-200 μg/mL. Hierarchical clustering analysis and linear discriminant analysis results indicated that the sensor array TPPE-SA can be successfully applied for accurate discrimination of different glycosaminoglycans, detecting trace glycosaminoglycan contaminants in heparin and monitoring the heparin concentration in diluted serum samples with almost 100% accuracy.