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 pi-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<middle dot><middle dot><middle dot>pi, 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 mu g/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.