Carbon Nanodots as Dual-Mode Nanosensors for Selective Detection of Hydrogen Peroxide

Hydrogen peroxide (H(2)O(2)) is an important product of oxidase-based enzymatic reactions, such as glucose/glucose oxidase (GOD) reaction. Therefore, the probing of generated H(2)O(2) for achieving the detection of various carbohydrates and their oxidases is very significative. Herein, we report one kind of dual-emission carbon nanodots (CDs) that can serve as novel dual-mode nanosensors with both fluorometric and colorimetric output for the selective detection of H(2)O(2). The dual-model nanosensors are established only by the undecorated dual-emission CDs, where significant fluorometric and colorimetric changes are observed with the addition of different concentrations of H(2)O(2) in the CD solution, which benefit to the achievement of the naked-eye detection for H(2)O(2). The mechanism of the nanosensors can be attributed to the fact that the external chemical stimuli like hydroxyl radicals from H(2)O(2) bring about the change of surface properties and the aggregation of CDs, which dominate the emission and absorption of CDs. The constructed dual-mode nanosensors exhibit good biocompatibility and high selectivity toward H(2)O(2) with a linear detection range spanning from 0.05 to 0.5 M and allow the detection of H(2)O(2) as low as 14 mM. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s11671-017-2214-6) contains supplementary material, which is available to authorized users.