Signal-on bimodal sensing glucose based on enzyme product-etching MnO_2 nanosheets for detachment of MoS_2 quantum dots

The sensitive and rapid detection of blood glucose is very important for monitoring and managing diabetes. Herein, a fluorescent/magnetic bimodal sensing strategy is proposed for glucose detection using a multifunction-responsive nanocomposite (MoS₂ QDs-MnO₂ NS). MoS₂ QDs act as fluorescent probes, and MnO₂ nanosheets are used as both quenchers and recognizers in this sensing platform. In the presence of glucose-mediated enzyme product (H₂O₂), MnO₂ nanosheet is etched, thus releasing MoS₂ QDs and Mn²⁺ ions, which causes the significantly enhancement of fluorescent and magnetic signals. Furthermore, MoS₂ QDs-MnO₂ NS-based fluorescent test paper is constructed for H₂O₂ sensing with the naked eyes. Under optimal conditions, the dual linear ranges of 20?300 μmol/L and 40?250 μmol/L toward glucose detection are obtained for the fluorescent and magnetic mode, respectively. Furthermore, this bimodal assay exhibits good reproducibility and acceptable accuracy in glucose detection of clinical samples, demonstrating great versatility and flexibility of multifunctional probes in glucose detection.