Efficient core shell structured dual response ratiometric fluorescence probe for determination of H2O2 and glucose via etching of silver nanoprisms.

A simple and sensitive inner filter effect and charge transfer dual response ratiometric fluorescent probe (D-RFP) for sensing glucose was developed based on etching of silver nanoprisms (Ag NPRs). The D-RFP was proposed by hybridizing red emitting CdTe QDs and blue emitting CDs into core-shell structured silica nanoparticles. In this design, when mixed Ag NPRs with the D-RFP, QDs which embedded in silica nanoparticles can be quenched by Ag NPRs via inner filter effect. Ag NPRs can be effectively etched to silver ions by H2O2 which can bind with CDs and quench CDs by charge transfer. The etching of Ag NPRs leaded to the recovering the fluorescence of QDs and quenching the fluorescence of CDs. Under optimal condition, D-RFP can be exploited for H2O2 detection with detection limit of 0.28 μM and glucose sensing with detection limit of 0.64 μM. The developed approach was applied to monitor glucose levels in human serum samples with satisfactory results. Moreover, this method provided a new idea for designing D-RFP and can be extended to other detection systems based on silver nanoparticles (including Ag NPs, Ag NPRs, or Au@Ag nanorods) etching process.