School of Mechanical and Materials Engineering, Washington State University , Pullman, Washington 99164, United States.
Department of Analytical Chemistry, College of Chemistry, Jilin University , Changchun 130012, P. R. China.
ACS Appl Mater Interfaces. 2016 Aug 31;8(34):21990-6. doi: 10.1021/acsami.6b05465. Epub 2016 Aug 17.
Glutathione (GSH) monitoring has attracted extensive attention because it serves a vital role in human pathologies. Herein, a convenient fluorescence "turn off-on" nanosensor based on graphene quantum dots (GQDs)-manganese dioxide (MnO2) nanosheet has been designed for selective detection of GSH in living cells. The fluorescence intensity of GQDs can be quenched by MnO2 nanosheets via a fluorescence resonance energy transfer. However, GSH can reduce MnO2 nanosheets to Mn(2+) cations and release GQDs, causing sufficient recovery of fluorescent signal. The MnO2 nanosheets serve as both fluorescence nanoquencher and GSH recognizer in the sensing platform. The sensing platform displayed a sensitive response to GSH in the range of 0.5-10 μmol L(-1), with a detection limit of 150 nmol L(-1). Furthermore, the chemical response of the GQDs-MnO2 nanoprobe exhibits high selectivity toward GSH over other electrolytes and biomolecules. Most importantly, the promising platform was successfully applied in monitoring the intracellular GSH in living cells, indicating its great potential to be used in disease diagnosis. Meanwhile, this GQDs-MnO2 platform is also generalizable and can be easily expanded to the detection and imaging of other reactive species in living cells.
谷胱甘肽（GSH）监测引起了广泛关注，因为它在人类病理学中起着至关重要的作用。在此，设计了一种基于石墨烯量子点（GQDs）-二氧化锰（MnO2）纳米片的简便荧光“关闭-开启”纳米传感器，用于选择性检测活细胞中的 GSH。MnO2 纳米片可以通过荧光共振能量转移猝灭 GQDs 的荧光强度。然而，GSH 可以将 MnO2 纳米片还原为 Mn(2+)阳离子并释放 GQDs，从而充分恢复荧光信号。MnO2 纳米片在传感平台中既充当荧光纳米猝灭剂又充当 GSH 识别器。该传感平台对 GSH 的响应范围为 0.5-10 μmol L(-1)，检测限为 150 nmol L(-1)。此外，GQDs-MnO2 纳米探针的化学响应对 GSH 具有较高的选择性，超过了其他电解质和生物分子。最重要的是，该有前途的平台成功应用于监测活细胞内的细胞内 GSH，表明其在疾病诊断中的巨大应用潜力。同时，该 GQDs-MnO2 平台具有通用性，可轻松扩展到活细胞中其他活性物质的检测和成像。
