Ionic liquid decorated AIE luminogen for selective detection of HSA in biofluids and early disease screening

The precise evaluation of human serum albumin (HSA) contents in biofluids is critical due to its important physiological functions. A fluorescent luminogen TPE-IL is facilely fabricated in present study by decorating the aggregation induced emission (AIE) dye E-1,2-bis(4-hydroxyphenyl)-1,2-diphenylethylene (TPE-OH) with ionic liquid (IL) HOOCMIMBr. The hydrophobic and hydrogen-bond interactions between the amino acid residues of HSA and TPE-IL lead to the spontaneous and energetically favorable docking of TPE-IL molecules in the hydrophobic subdomain of HSA, inducing the significant fluorescence enhancement of this sensor. Highly sensitive and selective detection of HSA is accomplished in the linear range of 0.02-10 μg/mL, with a detection limit of 0.007 μg/mL. The practicability of this sensor is validated by the accurate detection of HSA contents in human serum and urine samples. A glass slide-based visual sensing platform is also constructed to offer simple and fast HSA content evaluation in serum for early disease screening.