Simultaneous detection of hydrogen peroxide and glucose in human serum with upconversion luminescence

In this paper, a green upconversion photoluminescence (UCPL) system for the highly sensitive and selective detection of H2O2 and glucose in human sera was developed by utilizing the excellent optical properties of NaYF4:Yb3+/Er3+ upconversion nanoparticles (UCNPs). In the presence of H2O2, the colorless 3,3′,5,5′-tetramethylbenzidine (TMB) was oxidized into blue oxidized TMB (oxTMB) by assistance of horseradish peroxidase (HRP). And the green UCPL of UCNPs was quenched by the oxTMB linearly over the range of 100 nM-4.0 μM with a low limit of detection (LOD) of 45.0 nM for H2O2. Based on the transformation of glucose into H2O2 by means of glucose oxidase, the TMB-UCNPs-HRP system was further exploited for the highly sensitive detection of glucose in the range of 0.1-5.0 μM with a LOD of 64.0 nM in human sera independent of preconcentration and purification. The results are in good agreement with the clinical data, suggesting that this UCPL nanosensor is highly practical.