Dual-channel fluorescent probe for discriminative detection of H2S and N2H4: Exploring sensing mechanism and real-time applications

A highly efficient system incorporates the real-time visualization of the two toxic molecules (H2S and N2H4) and the recognition of corresponding transforms using a fluorescent sensor. In this paper, a dual-responsive probe (QS-DNP) based on methylquinolinium-salicyaldehyde-2,4-dinitrophenyl was developed that can simultaneously detect H2S and N2H4 at two independent fluorescent channels without signal crosstalk. QS-DNP showed excellent anti-interference, high selectivity, outstanding water solubility, low LOD values (H2S: 51 nM; N2H4: 40 nM), low cytotoxicity, and mitochondrial localization properties. The 2,4-dinitrophenyl site was sensitive to H2S, and the CC bridge was reactive to N2H4, with strong fluorescence at 680 and 488 nm, respectively. The wavelength gap between these two channels is 192 nm; verify that there is no signal crosstalk throughout detection. By this means, the probe was used to simultaneously detect H2S and N2H4 in real soil samples, food samples, and living cells. The endogenous H2S and N2H4 were monitored in HeLa cells and investigated the mitochondria organelle of living cells with a positive charge on QS-DNP. Overall, all results emphasize that the QS-DNP probe is a powerful tool for the simultaneous detection of H2S and N2H4 and presents a potential new sensing approach. A dual-responsive sensor, QS-DNP, was successfully developed to track H2S and N2H4 individually and non-invasively at their own channels endogenously in living HeLa cells. [Display omitted] •A dual-responsive probe, QS-DNP was designed to track H2S and N2H4 in its channel.•The intramolecular charge transfer as the sensing strategies was investigated.•Detection limit values of 51 and 40 nM for H2S and N2H4, respectively, are gained.•Probe exhibited water solubility, endogenous (H2S, N2H4), & mito-tracking ability.•Distinctive images in cells were observed in red (H2S) and green (N2H4) channels.