A new efficient and practical fluorescent probe 6-(benzo[d]thiazol-2-yl)naphthalen-2-yl-thiophene-2-carboxylate (probe
Hydrogen sulfide (H2S) has unpleasant rotten egg smell [
H2S is an important part in the processes of physiological and pathophysiological responses, and abnormal levels of H2S cause various diseases [
The methods to detect H2S include colorimetry [
The chemicals and reagents were purchased from Beijing Huaxue Shiji (Beijing, P.R. China). The reagents were all analytically pure. 1H-NMR and 13C-NMR spectra were recorded at 400 MHz and 100 MHz, respectively. Chemical shifts (
Synthesis of probe
1H NMR (300 MHz, DMSO),
Probe
1H NMR (300 MHz, DMSO),
The HPLC-grade DMSO as reagent was used to dissolved probe
Three kinds of beers and four kinds of red wines were bought from wumart supermarket (Beijing) and different concentrations of Na2S were added (Na2S is the H2S source), and the 504 nm fluorescence signals of samples were recorded.
The ready of the detection system: dimethyl sulfoxide (0.48 mL) and probe solution (0.02 mL) were mixed. And then buffer solution was added and made up to 2 mL in the cuvette. After mixing, the spectrum was tested by recording the fluorescence signals.
Fluorescence spectrophotometer parameters: excitation wavelength, 330 nm; emission wavelength, 504 nm; temperature, 37°C; voltage, 700 v; slit width, 5 nm/5 nm.
Probe
The fluorescence response of probe
(a) Time-dependent fluorescence spectra of probe
The fluorescent response of probe
(a) Fluorescent intensity of probe
The fluorescence response of probe
The solution of probe
(a) Fluorescence spectra of probe
To verify the selectivity of probe
A possible response mechanism may attribute to H2S-induced hydrolysis of thenoic acid ether moiety in probe
The mechanism for probe
As H2S negatively affects wine quality, it is an important reason to cause faulty wine. The data of probe
As shown in Table
Determination of H2S concentrations in wine.
Sample | H2S level found ( |
Added ( |
H2S level found ( |
Recovery (%) |
|
---|---|---|---|---|---|
Red wine A | 0.53 | 50 | 53.02 | 104.88 | 0.007 |
100 | 100.21 | 99.68 | 0.005 | ||
Red wine B | 0.69 | 50 | 48.90 | 96.47 | 0.001 |
100 | 98.14 | 97.33 | 0.004 | ||
Red wine C | 0.74 | 50 | 46.10 | 90.65 | 0.005 |
100 | 97.14 | 96.28 | 0.005 | ||
Red wine D | 0.49 | 50 | 47.96 | 94.99 | 0.004 |
100 | 98.12 | 97.64 | 0.006 | ||
Beer A | 0.41 | 50 | 50.71 | 100.59 | 0.004 |
100 | 100.32 | 99.91 | 0.005 | ||
Beer B | 0.28 | 50 | 49.10 | 97.65 | 0.002 |
100 | 100.34 | 100.00 | 0.006 | ||
Beer C | 0.32 | 50 | 55.36 | 110.00 | 0.001 |
100 | 105.43 | 105.09 | 0.005 |
The test was repeated 3 times.
Probe
In summary, we developed a sensitive and visible colorimetric fluorescent probe to detect H2S. The function of probe
The data used to support the findings of this study are included within the article.
The authors declare that there are no conflicts of interest regarding the publication of this article.
The authors thank the Scientific and Technological Innovation and Service Capacity Building (basic research business funding) for funding the study on the flavor of typical Chinese traditional dishes (PXM2018-014213-000033) and the Support Project of High-Level Teachers in Beijing Municipal Universities in the period of 13th Five-Year Plan (CIT&TCD201804021).
Experiment section. Figure S1: 1H NMR spectra of 6-(benzo[d]thiazol-2-yl)naphthalen-2-ol. Figure S2: 13C NMR spectra of 6-(benzo[d]thiazol-2-yl)naphthalen-2-ol. Figure S3: 1H NMR spectra of probe