Paper-based fluorescent devices for multifunctional assays: Biomarkers detection, inhibitors screening and chiral recognition

Abstract

The development of a single analytical platform with different functions is highly desirable but remains a challenge at present. Here, a paper-based device based on fluorescent carbon dots (CDs) functionalized paper/MnO2 nanosheets (MnO2 NS) hybrid devices (PCD/NS) was proposed for single-device multi-function applications. MnO2 NS functioned as a fluorescence quencher of CDs and recognizer of H2O2 released from the oxidase catalyzed system. Fluorescence recovery would occur after the decomposition of MnO2 NS induced by H2O2, by which a simple and effective strategy could be developed for fluorescence monitoring multiplex biological events. Xanthine (XA) sensing, xanthine oxidase (XOD) inhibitors screening analysis and chiral recognition of glucose enantiomers were performed on PCD/NS to investigate the multifunctional application of the paper-based device. By means of PCD/NS, XA could be determined in the range of 0.1–40 µmol/L with a low detection of limit of 0.06 µmol/L. The IC50 value of allopurinol, the model inhibitor of XOD, was sensitively detected to be 7.4 µmol/L. Glucose enantiomers were also recognized in terms of the specific fluorescence response to d-glucose. This work firstly presented a paper-based device capable of biomarkers detection, inhibitors screening and chiral recognition, which enlightened a promising strategy for the construction of multifunctional devices and hold the great potential application in clinical diagnosis and drug discovery.