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The redox homeostasis between glutathione (GSH) and peroxynitrite (ONOO-) is essential for maintaining normal physiological functions in biological system, and the imbalance of GSH and ONOO- is closely related to the pathogenesis of diverse diseases. Herein, we presented a dual-fluorophore and dual-site probe for the simultaneous detection of mitochondrial GSH and ONOO- via the integrated mechanism of ICT and FRET. The probe exhibited favorable response performance toward GSH and ONOO- at pH 7.4 including high sensitivity, fast response and superior selectivity. Especially, there was no interfering fluorescent signals of ONOO- (or GSH) during the detection of GSH (or ONOO-) alone, while significant fluorescence variation was observed during detecting ONOO- (or GSH) in the presence of GSH (or ONOO-). Therefore, the probe could monitor the coexistence of GSH and ONOO- not just the separate existence of GSH or ONOO-. Given these advantages, Mito-CM-CD has been successfully utilized for real-time visualization of GSH and ONOO- in normal HepG2 cells and drug-induced HepG2 cells. Importantly, it has been found that depletion of GSH and indirect formation of ONOO- are associated with the APAP-induced liver injury which can be effectively relieved by supplementing GSH. We anticipated that this research will promote to understand the interrelation of GSH and ONOO- under different physiological and pathological settings. [Display omitted] • Mito-CM-CD exhibited rapid response, high selectivity and low LOD to ONOO- and GSH. • The probe displayed quenched signal to ONOO- but enhanced signal to GSH at 640 nm under single-wavelength excitation. • Mito-CM-CD could sense ONOO- (or GSH) with enhanced blue but decreased red fluorescence in the presence of GSH (or ONOO-). • Confocal microscopy experiments indicated that Mito-CM-CD can be used for visualizing GSH and ONOO- in living cells. [ABSTRACT FROM AUTHOR]

• The top silicon of the SOI substrate was used as the thermistor's supporting layer. • The dead volume of the μTCD was as small as about 200 nL. • The detection level of the μTCD was as low as 5 ppm. In this paper, a micro thermal conductivity detector (TCD) with suspended thermistors based on a Silicon-On-Insulator (SOI) substrate was successfully fabricated by using a MEMS technique. The top layer of silicon of the SOI substrate was utilized as the supporting layer of the thermistor, which possessed excellent mechanical strength. The buried SiO 2 was utilized as the etch stop layer of deep reactive ion etching in the thermistor release process, which precisely defined the channels with a high depth-to-width ratio and acquired an ultra-small dead volume (∼200 nL). The micro TCD showed sensitive detection at levels as low as 5 ppm of n-alkanes C14-C16 mixtures. Besides, the micro TCD demonstrated excellent universal detection to gas mixtures, which detected all thirteen analytes in the standard sample of n-alkanes C8-C20 mixtures and all eight analytes in the standard sample of VOCs (volatile organic compounds). [ABSTRACT FROM AUTHOR]