Search

The development of reliable bioanalytical probes for sensitive and specific detection of hydrogen sulfide (H 2 S) plays important role for better understanding the roles of this biomolecule in living cells and organisms. Taking advantages of unique photophysical properties of ruthenium(II) (Ru(II)) complex, this work presents the development of a responsive Ru(II) complex probe, Ru-PNBD , for colorimetric and luminescent analysis of H 2 S in living cells and organisms. In aqueous solution, Ru-PNBD is yellow color and non-luminescent because of the photoinduced electron transfer (PET) process from Ru(II) complex luminophore to NBD moiety. The H 2 S-triggered specific nucleophilic substitution reaction with Ru-PNBD cleaves the NBD moiety to form pink NBD-SH and highly luminescent Ru-PH. The color of the solution thus changes from yellow to pink for colorimetric analysis and the emission intensity is about 65-fold increased for luminescent analysis. Ru-PNBD has high sensitivity and selectivity for H 2 S detection, low cytotoxicity and good permeability to cell membrane, which allow the application of this probe for H 2 S imaging in living cells, Daphnia magna , and larval zebrafish. Collectively, this work provides a useful tool for H 2 S analysis and expands the scope of transition metal complex probes. We present the development of a responsive ruthenium(II) complex probe, Ru-PNBD , for colorimetric and luminescent detection of hydrogen sulfide in living cells and organisms. Image 1 • A responsive ruthenium(II) complex, Ru-PNBD , is developed as the luminescence probe for hydrogen sulfide detection. • The Ru-PNBD can sensitively and selectively respond to H 2 S and give color change and luminescence enhancement. • Mechanisms of response reaction and luminescence "OFF-ON" response are investigated. • The application of Ru-PNBD for the detection of H 2 S in living cells and organisms is demonstrated. [ABSTRACT FROM AUTHOR]

In this work, a "two birds with one stone" ruthenium(II) complex probe, Ru‐NBD, is proposed as an effective tool for biothiols detection and discrimination in vitro and in vivo. Ru‐NBD is nonluminescent due to the quenching of Ru(II) complex emission by photoinduced electron transfer (PET) from Ru(II) center to NBD and the quenching of NBD emission through 4‐substitution with "O" ether bond. Ru‐NBD is capable of reacting with Cys/Hcy to form long‐lived red‐emitting Ru‐OH and short‐lived green‐emitting NBD‐NR, while reacting with GSH to produce Ru‐OH and nonemissive NBD‐SR. The long lifetime emission of Ru(II) complex allows elimination of short lifetime background and NBD‐NR fluorescence for total biothiols detection ("bird" one) by time‐gated luminescence (TGL) analysis, and the remarkable difference in luminescence color response allows discrimination GSH and Cys/Hcy ("bird" two) through steady‐state luminescence analysis. Ru‐NBD features high sensitivity and selectivity, rapid luminescence response, and low cytotoxicity, which enables it to be used as the probe for luminescence and background‐free TGL detection and visualization of biothiols in live cells, zebrafish, and mice. The successful development of this probe is anticipated to contribute to the future biological studies of biothiols roles in various diseases. [ABSTRACT FROM AUTHOR]

Sensitive and selective quantification of specific analytes is of great significance in analytical and environmental sciences, as well as in the food industry. Herein, we report the design, synthesis, characterization, and application of a responsive ruthenium(II) complex probe, Ru-azo, for phosphorescence and time-gated luminescence (TGL) detection of bisulfite, an important additive in the food industry. Upon a specific nucleophilic addition reaction between bisulfite and the azo group of Ru-azo, a new ruthenium(II) complex, Ru-SO3, was obtained, which resulted in a remarkable increase in phosphorescence intensity, allowing the bisulfite detection to be achieved. In addition, long-lived emissions of Ru-azo (τ = 258 ns) and Ru-SO3 (τ = 261 ns) also enabled the TGL detection of bisulfite in autofluorescence-rich food samples. Through theoretical computations, the photoinduced electron transfer (PET) process within the ruthenium(II) complex was validated, which unveiled the rationality of the luminescence "off-on" response of Ru-azo to bisulfite. The probe showed advantages of good water solubility, and high sensitivity, selectivity and accuracy for responding to bisulfite, facilitating its application in phosphorescence and TGL detection of bisulfite in aqueous and food samples. [ABSTRACT FROM AUTHOR]