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Cite this: Chem. Commun., 2014, 50, 1485 Received 30th October 2013, Accepted 28th November 2013
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Hydrazine detection in the gas state and aqueous solution based on the Gabriel mechanism and its imaging in living cells† Lei Cui,*ab Zhixing Peng,a Chunfei Ji,a Junhai Huang,c Dongting Huang,a Jie Ma,a Shuping Zhang,*a Xuhong Qianb and Yufang Xu*b
DOI: 10.1039/c3cc48304e www.rsc.org/chemcomm
A new probe based on the Gabriel mechanism was designed and first used for hydrazine detection with high selectivity against other amines in aqueous solution. Importantly, the probe could be used for gas-state discrimination of hydrazine with different concentrations. Additionally, probe 1 could also be applied for the imaging of hydrazine in living cells.
As an important chemical reagent, hydrazine is widely used in pharmaceuticals, pesticides, photography chemicals, emulsifiers, dyes, corrosion inhibitors and textile dyes in various chemical industries.1 Because of its high enthalpy of combustion, hydrazine is also well applied in missile and rocket propulsion systems as a propellant.2 On the other hand, hydrazine is highly toxic and could be readily absorbed during manufacture, usage, transport and disposal. The U.S. Environmental Protection Agency (EPA) has identified hydrazine as a probable human carcinogen with a low threshold limit value (TLV) of 10 ppb. Animal experiments have also shown that hydrazine is mutagenic and carcinogenic and could cause severe damage to the liver, lungs, kidneys and human central nervous system.3 Various methods for hydrazine detection are available, including chromatography mass spectrometric4 and electrochemical methods.5 However, only a few papers are concerned with fluorescence methods for the detection of hydrazine.6 Fluorescence based techniques have some obvious advantages, such as non-invasiveness, high sensitivity, and spatiotemporal resolution, and have been viewed as a powerful and versatile toolbox in the field of environmental monitoring, life sciences and disease diagnosis.7
Herein, we describe a novel OFF–ON fluorescent probe 1 based on Gabriel synthesis. Gabriel synthesis is named after the German chemist Siegmund Gabriel.8 Traditionally, this chemical reaction transforms primary alkyl halides into primary amines using potassium phthalimide, and then liberates the amine from the phthalimide upon hydrazinolysis or acidic hydrolysis. Typically, because of the high reaction activity, hydrazinolysis provides better results, faster response and more moderate reaction conditions. Here, we induced the fluorophore 4-amino-1,8-naphthalimide 2 to the phthalimide part and designed probe 1 for the detection of hydrazine. Upon reduction, the amino group of 4-amino-1,8-naphthalimide will be released and the fluorescence will be restored. Both probe 1 and the hydrazinolysis product were efficiently synthesized (Scheme 1) and well characterized. The detailed synthetic procedures (Scheme S1, ESI†) and related spectra are described in the ESI.† Next, we studied their spectral characteristics in chemical and cell media. Spectroscopic evaluation of 1 and 2 was carried out at room temperature in water and DMSO (4 : 6, v/v) after 2 min of mixing (Fig. S1, ESI†). The absorption spectra of 1 and 2 have an intersection at the wavelength of 375 nm. Here, we chose 380 nm as the excitation wavelength. The pH titration showed that the fluorescent intensity is stable enough in a large pH range from 2 to 12 (Fig. S2, ESI†).
a
College of Science, School of Environment and Architecture, University of Shanghai for Science and Technology, (USST), Shanghai, China. E-mail: [email protected] b Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China University of Science and Technology, (ECUST), Shanghai 200237, China. E-mail: [email protected]; Fax: +86-21-64252603; Tel: +86-21-64252603 c Shanghai Institute of Pharmaceutical Industry, Shanghai, China † Electronic supplementary information (ESI) available: Experimental, synthetic, spectroscopic, and bioassay details. See DOI: 10.1039/c3cc48304e
This journal is © The Royal Society of Chemistry 2014
Scheme 1 The synthetic route for preparation of probe 1 and the proposed hydrazinolysis mechanism.
Chem. Commun., 2014, 50, 1485--1487 | 1485
View Article Online
Published on 29 November 2013. Downloaded by The University of Manchester Library on 27/10/2014 00:25:30.
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We then tested the hydrazinolysis sensitivity of the designed probe 1. Titration experiments were carried out by gradually adding hydrazine to the probe and collecting the absorption and fluorescence emission spectra. We found that there was a dramatic change in the absorption and fluorescence signals after addition of trace amounts of hydrazine. The UV-vis spectra of 1 exhibited a maximum absorption at 340 nm. Upon addition of hydrazine, the absorption at 340 nm evidently decreased, whereas a new absorption peak appeared at 440 nm, which is characteristic of 2, with an isosbestic point at 380 nm. The color of the solution clearly changed from colorless to yellow, enabling good colorimetric detection of hydrazine by naked eyes. Accordingly, upon excitation at 420 nm, a new emission peak at 540 nm appeared, which gradually increased in intensity with increased hydrazine concentration (Fig. 1). These changes in the fluorescence spectra stopped when the amount of added hydrazine reached 1.5 equivalents of the probe. The fluorescence intensity increased about 100 times after the hydrazine was added and the color of the fluorescence changed from colourless to yellow. Probe 1 exhibited an ‘OFF–ON’ signal change for hydrazine detection. A linear relationship was observed between I540 and [N2H4] in the range of 1–50 mM (Fig. S3, ESI†). The relationship between emission at 540 nm and hydrazine concentration is: y = 5.681 + 13.726 x, where y is the fluorescence intensity under the emission at 540 nm and x is the concentration of hydrazine. The linear range of the method was found to be at least 0.1–70 mM hydrazine with a correlation coefficient of R2 = 0.9908. The detection limit, based on the definition of IUPAC (CDL = 3 Sbm 1),9 was found to be 8.8 10 9 M (0.3 ppb), which is lower enough than the TLV (10 ppb). The relative standard deviation (RSD) for three repeated measurements of 2.5 10 7 M hydrazine was 5.2%. Probe 1 with a high sensitivity and the linear response to the concentration of hydrazine is potentially used for the detection of trace concentrations of hydrazine in practical samples. The response time was then investigated, as shown in Fig. S4 (ESI†). The reaction could be completed in 100 s after the addition of hydrazine (10 equiv.) to probe 1. Because the leaving group 4-amine1,8-naphthalimide is a stronger electron-withdrawing group (with low pKa) than the primary amine, the reactivity increase is obvious. This is consistent with a typical nucleophilic substitution reaction which has been proved before.10 To the best of our knowledge, probe 1 showed the fastest response to hydrazine among all reported probes.
Fig. 1 UV-vis (left) and fluorescence emission (right) spectra of probe 1 (50 mM) of hydrazine in H2O with DMSO (4 : 6, v/v).
1486 | Chem. Commun., 2014, 50, 1485--1487
ChemComm
Fig. 2 Fluorescence responses of probe 1 (50 mM) to hydrazine and other species. Each spectrum was recorded after 2 min of reaction in a mixture of water and DMSO (4 : 6, v/v) at r.t. to various representative species and primary amines (50 mM): (1) blank; (2) hydrazine; (3) n-butylamine; (4) ethylenediamine; (5) ammonia; (6) cysteine; (7) lysine; (8) glutamine; (9) urea; (10) hydroxylamine; (11) thiourea; (12) triethylamine; (13) acetaldehyde; (14) mixture.
As a first reported recognition mechanism toward hydrazine, the selectivity of probe 1 was also tested in our present work (Fig. 2). It was found that primary amines, such as ammonia, n-butylamine and ethylenediamine, could cause the increase of fluorescent intensity by about 12% of that caused by hydrazine at a low concentration (100 mM) (Fig. S5, ESI†). The selectivity of probe 1 to other species was also tested (Fig. S6, ESI†). Almost no fluorescence intensity changes were observed in emission spectra with Hg2+, Co2+, Cr3+, Cd2+, Fe3+, Ni2+, Zn2+, Cu2+, Al3+, Mg2+, Ca2+ and Ag+. Furthermore, under identical conditions, the metal cations cause no change to the fluorescence emission spectra of 1, so probe 1 can respond to hydrazine in the presence of these metal cations (50 equiv.). Similar test results were observed on the selectivity to anion detection (Cl , Br , I , SO42 , SO32 , ClO4 , HCO3 , SCN and HPO42 ) (Fig. S6, ESI†). Thus probe 1 showed excellent selectivity to hydrazine. Most importantly, probe 1 could be applied for the detection of gas-state hydrazine which can further discriminate hydrazine aqueous solutions of different concentrations. To make the detection experiments easy to perform and practical, a TLC plate was used. Prior to detection, a glass TLC plate was firstly immersed into a methanol solution of 1 (5 mM) and dried, then the probe-loaded TLC plate was covered on the top of a jar containing hydrazine solution for 10 min at r.t. before it was ready to observe. As shown in Fig. 3, the change in the color of the fluorescence from colorless to yellow was observed using a hand-held UV lamp with excitation at 365 nm. The gas state hydrazine detection limit of probe 1 is 111.7 mg m 3 which is well below the half lethal dose of hydrazine gas for mice (330 mg m 3).11 Moreover, the fluorescence intensity of the probe on the TLC plate was dependent on the concentration of hydrazine in aqueous solution and was easy to distinguish by naked eyes. Hydrazine in gaseous form often threatens human life, so our designed probe has more application potential. To further demonstrate the application potential of probe 1 in living cells, the probe was applied in Hela cells for fluorescence
This journal is © The Royal Society of Chemistry 2014
View Article Online
Published on 29 November 2013. Downloaded by The University of Manchester Library on 27/10/2014 00:25:30.
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Fig. 3 Visual and fluorescence color changes of probe 1 (5.0 mM)-coated TLC plates after exposure to the different concentration of hydrazine aqueous solution. The fluorescence color changes were observed using a hand-held UV lamp with an excitation at 365 nm.
Communication
for the discrimination of different concentrations of gas-state hydrazine with the detection limit of 111.7 mg m 3, with an easy and practical method, which provided a convenient way for hydrazine detection. Finally, the living cell imaging of hydrazine further proved the great potential of the probe for practical utilization. This work is financially supported by the National Natural Science Foundation of China (21236002, 21202097), the National Basic Research Program of China (973 Program, 2010CB126100), the National High Technology Research and Development Program of China (863 Program 2011AA10A207), and the Fundamental Research Funds for the Central Universities.
Notes and references
Fig. 4 Fluorescence images of HeLa cells. Cells were incubated with probe 1 (10 mM) for 30 min (a–c); image of cells after treatment with probe 1 (10 mM) for 30 min and subsequent treatment of the cells with 50 mM hydrazine for 20 min (d–f). (a and d) Bright-field images of the HeLa cells in samples; (b and e) images were taken between 540–580 nm (green); and (c and f) is the overlap of brightfield and fluorescence. Scare bar: 20 mm.
imaging of hydrazine. Hela cells incubated with 1 (10 mM) for 20 min at 37 1C in PBS buffer with 0.5% DMSO showed nearly no intracellular fluorescence. When hydrazine (50 mM) was added and then incubated for further 10 min, a strong fluorescence signal was observed and collected in the green channel from 520 nm to 560 nm with 1/5 s exposure time (Fig. 4). These cell experiments indicated that probe 1 could provide a sensitive and fast response to hydrazine in cells. In summary, we have first developed a selective fluorescent probe 1 for hydrazine detection based on Gabriel synthesis. The probe could selectively react with hydrazine, resulting in an OFF–ON fluorescence signal change at 540 nm and the colour changes from colourless to yellow at room temperature within 2 minutes. The solution detection limit of 1 was found to be 0.3 ppb, which is far below the 10 ppb limit for hydrazine exposure set by the U.S. EPA. Importantly, probe 1 was successfully applied
This journal is © The Royal Society of Chemistry 2014
1 S. D. Zelnick, D. R. Mattie and P. C. Stepaniak, Aviat., Space Environ. Med., 2003, 74, 1285–1291; I. C. Vieira, K. O. Lupetti and O. Fatibello-Filho, Anal. Lett., 2002, 35, 2221–2231. 2 Hydrazine and Its Derivatives, in Kirk-Othmer Encyclopedia of Chemical Technology, ed. J. I. Kroschwitz and A. Seidel, Wiley, New York, 5th edn, 2005, vol. 13, pp. 562–607. 3 S. Garrod, M. E. Bollard, A. W. Nicholls, S. C. Connor, J. Connelly, J. K. Nicholson and E. Holmes, Chem. Res. Toxicol., 2005, 18, 115–122; C. A. Reilly, Chem. Res. Toxicol., 1997, 10, 328–334. 4 Y.-Y. Liu, I. Schmeltz and D. Hoffmann, Anal. Chem., 1974, 46, 885–889; J.-A. Oh, J.-H. Park and H.-S. Shin, Anal. Chim. Acta, 2013, 769, 79–83. 5 A. Umar, M. M. Rahman, S. H. Kim and Y.-B. Hahn, Chem. Commun., 2008, 166–168; J. Liu, Y. Li, J. Jiang and X. Huang, Dalton Trans., 2010, 39, 8693–8697. 6 M. H. Lee, B. Yoon, J. S. Kim and J. L. Sessler, Chem. Sci., 2013, 4, 4121–4126; C. Hu, W. Sun, J. Cao, P. Gao, J. Wang, J. Fan, F. Song, S. Sun and X. Peng, Org. Lett., 2013, 15, 4022–4025; M. G. Choi, J. O. Moon, J. Bae, J. W. Lee and S. K. Chang, Org. Biomol. Chem., 2013, 11, 2961–2965; J. Fan, W. Sun, M. Hu, J. Cao, G. Cheng, H. Dong, K. Song, Y. Liu, S. Sun and X. Peng, Chem. Commun., 2012, 48, 8117–8119; M. G. Choi, J. Hwang, J. O. Moon, J. Sung and S. K. Chang, Org. Lett., 2011, 13, 5260–5263; Y.-D. Lin and T. J. Chow, RSC Adv., 2013; K. Li, H.-R. Xu, K.-K. Yu, J.-T. Hou and X.-Q. Yu, Anal. Methods, 2013, 5, 2653–2656. 7 K. Wang, X. He, X. Yang and H. Shi, Acc. Chem. Res., 2013, 46, 1367–1376; L. Yuan, W. Lin, K. Zheng and S. Zhu, Acc. Chem. Res., 2013, 46, 1462–1473; L. Yuan, W. Lin, K. Zheng, L. He and W. Huang, Chem. Soc. Rev., 2013, 42, 622–661; H. Li, J. Fan and X. Peng, Chem. Soc. Rev., 2013, 42, 7943–7962. 8 M. S. Gibson and R. W. Bradshaw, Angew. Chem., Int. Ed. Engl., 1968, 7, 919–930. 9 H. M. N. H. Irving, H. Freiser and T. S. West, IUPAC Compendium of Analytical Nomenclature, Definitive Rules, Pergamon Press, Oxford, 1981. 10 M. R. Crampton, T. A. Emokpae and C. Isanbor, J. Phys. Org. Chem., 2006, 19, 75–80; M. B. Smith, in March’s Advanced Organic Chemistry, ed. J. March, New York, John Wiley, 5th edn, 2001, p. 860; R. Ormazabal-Toledo, R. Contreras, R. A. Tapia and P. R. Campodonico, Org. Biomol. Chem., 2013, 11, 2302–2309. 11 U.S. Department of Health and Human Services. Registry of Toxic Effects of Chemical Substances (RTECS, online database). National Toxicology Information Program, National Library of Medicine, Bethesda, MD, 1993.
Chem. Commun., 2014, 50, 1485--1487 | 1487
COMMUNICATION
Cite this: Chem. Commun., 2014, 50, 1485 Received 30th October 2013, Accepted 28th November 2013
View Article Online View Journal | View Issue
Hydrazine detection in the gas state and aqueous solution based on the Gabriel mechanism and its imaging in living cells† Lei Cui,*ab Zhixing Peng,a Chunfei Ji,a Junhai Huang,c Dongting Huang,a Jie Ma,a Shuping Zhang,*a Xuhong Qianb and Yufang Xu*b
DOI: 10.1039/c3cc48304e www.rsc.org/chemcomm
A new probe based on the Gabriel mechanism was designed and first used for hydrazine detection with high selectivity against other amines in aqueous solution. Importantly, the probe could be used for gas-state discrimination of hydrazine with different concentrations. Additionally, probe 1 could also be applied for the imaging of hydrazine in living cells.
As an important chemical reagent, hydrazine is widely used in pharmaceuticals, pesticides, photography chemicals, emulsifiers, dyes, corrosion inhibitors and textile dyes in various chemical industries.1 Because of its high enthalpy of combustion, hydrazine is also well applied in missile and rocket propulsion systems as a propellant.2 On the other hand, hydrazine is highly toxic and could be readily absorbed during manufacture, usage, transport and disposal. The U.S. Environmental Protection Agency (EPA) has identified hydrazine as a probable human carcinogen with a low threshold limit value (TLV) of 10 ppb. Animal experiments have also shown that hydrazine is mutagenic and carcinogenic and could cause severe damage to the liver, lungs, kidneys and human central nervous system.3 Various methods for hydrazine detection are available, including chromatography mass spectrometric4 and electrochemical methods.5 However, only a few papers are concerned with fluorescence methods for the detection of hydrazine.6 Fluorescence based techniques have some obvious advantages, such as non-invasiveness, high sensitivity, and spatiotemporal resolution, and have been viewed as a powerful and versatile toolbox in the field of environmental monitoring, life sciences and disease diagnosis.7
Herein, we describe a novel OFF–ON fluorescent probe 1 based on Gabriel synthesis. Gabriel synthesis is named after the German chemist Siegmund Gabriel.8 Traditionally, this chemical reaction transforms primary alkyl halides into primary amines using potassium phthalimide, and then liberates the amine from the phthalimide upon hydrazinolysis or acidic hydrolysis. Typically, because of the high reaction activity, hydrazinolysis provides better results, faster response and more moderate reaction conditions. Here, we induced the fluorophore 4-amino-1,8-naphthalimide 2 to the phthalimide part and designed probe 1 for the detection of hydrazine. Upon reduction, the amino group of 4-amino-1,8-naphthalimide will be released and the fluorescence will be restored. Both probe 1 and the hydrazinolysis product were efficiently synthesized (Scheme 1) and well characterized. The detailed synthetic procedures (Scheme S1, ESI†) and related spectra are described in the ESI.† Next, we studied their spectral characteristics in chemical and cell media. Spectroscopic evaluation of 1 and 2 was carried out at room temperature in water and DMSO (4 : 6, v/v) after 2 min of mixing (Fig. S1, ESI†). The absorption spectra of 1 and 2 have an intersection at the wavelength of 375 nm. Here, we chose 380 nm as the excitation wavelength. The pH titration showed that the fluorescent intensity is stable enough in a large pH range from 2 to 12 (Fig. S2, ESI†).
a
College of Science, School of Environment and Architecture, University of Shanghai for Science and Technology, (USST), Shanghai, China. E-mail: [email protected] b Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China University of Science and Technology, (ECUST), Shanghai 200237, China. E-mail: [email protected]; Fax: +86-21-64252603; Tel: +86-21-64252603 c Shanghai Institute of Pharmaceutical Industry, Shanghai, China † Electronic supplementary information (ESI) available: Experimental, synthetic, spectroscopic, and bioassay details. See DOI: 10.1039/c3cc48304e
This journal is © The Royal Society of Chemistry 2014
Scheme 1 The synthetic route for preparation of probe 1 and the proposed hydrazinolysis mechanism.
Chem. Commun., 2014, 50, 1485--1487 | 1485
View Article Online
Published on 29 November 2013. Downloaded by The University of Manchester Library on 27/10/2014 00:25:30.
Communication
We then tested the hydrazinolysis sensitivity of the designed probe 1. Titration experiments were carried out by gradually adding hydrazine to the probe and collecting the absorption and fluorescence emission spectra. We found that there was a dramatic change in the absorption and fluorescence signals after addition of trace amounts of hydrazine. The UV-vis spectra of 1 exhibited a maximum absorption at 340 nm. Upon addition of hydrazine, the absorption at 340 nm evidently decreased, whereas a new absorption peak appeared at 440 nm, which is characteristic of 2, with an isosbestic point at 380 nm. The color of the solution clearly changed from colorless to yellow, enabling good colorimetric detection of hydrazine by naked eyes. Accordingly, upon excitation at 420 nm, a new emission peak at 540 nm appeared, which gradually increased in intensity with increased hydrazine concentration (Fig. 1). These changes in the fluorescence spectra stopped when the amount of added hydrazine reached 1.5 equivalents of the probe. The fluorescence intensity increased about 100 times after the hydrazine was added and the color of the fluorescence changed from colourless to yellow. Probe 1 exhibited an ‘OFF–ON’ signal change for hydrazine detection. A linear relationship was observed between I540 and [N2H4] in the range of 1–50 mM (Fig. S3, ESI†). The relationship between emission at 540 nm and hydrazine concentration is: y = 5.681 + 13.726 x, where y is the fluorescence intensity under the emission at 540 nm and x is the concentration of hydrazine. The linear range of the method was found to be at least 0.1–70 mM hydrazine with a correlation coefficient of R2 = 0.9908. The detection limit, based on the definition of IUPAC (CDL = 3 Sbm 1),9 was found to be 8.8 10 9 M (0.3 ppb), which is lower enough than the TLV (10 ppb). The relative standard deviation (RSD) for three repeated measurements of 2.5 10 7 M hydrazine was 5.2%. Probe 1 with a high sensitivity and the linear response to the concentration of hydrazine is potentially used for the detection of trace concentrations of hydrazine in practical samples. The response time was then investigated, as shown in Fig. S4 (ESI†). The reaction could be completed in 100 s after the addition of hydrazine (10 equiv.) to probe 1. Because the leaving group 4-amine1,8-naphthalimide is a stronger electron-withdrawing group (with low pKa) than the primary amine, the reactivity increase is obvious. This is consistent with a typical nucleophilic substitution reaction which has been proved before.10 To the best of our knowledge, probe 1 showed the fastest response to hydrazine among all reported probes.
Fig. 1 UV-vis (left) and fluorescence emission (right) spectra of probe 1 (50 mM) of hydrazine in H2O with DMSO (4 : 6, v/v).
1486 | Chem. Commun., 2014, 50, 1485--1487
ChemComm
Fig. 2 Fluorescence responses of probe 1 (50 mM) to hydrazine and other species. Each spectrum was recorded after 2 min of reaction in a mixture of water and DMSO (4 : 6, v/v) at r.t. to various representative species and primary amines (50 mM): (1) blank; (2) hydrazine; (3) n-butylamine; (4) ethylenediamine; (5) ammonia; (6) cysteine; (7) lysine; (8) glutamine; (9) urea; (10) hydroxylamine; (11) thiourea; (12) triethylamine; (13) acetaldehyde; (14) mixture.
As a first reported recognition mechanism toward hydrazine, the selectivity of probe 1 was also tested in our present work (Fig. 2). It was found that primary amines, such as ammonia, n-butylamine and ethylenediamine, could cause the increase of fluorescent intensity by about 12% of that caused by hydrazine at a low concentration (100 mM) (Fig. S5, ESI†). The selectivity of probe 1 to other species was also tested (Fig. S6, ESI†). Almost no fluorescence intensity changes were observed in emission spectra with Hg2+, Co2+, Cr3+, Cd2+, Fe3+, Ni2+, Zn2+, Cu2+, Al3+, Mg2+, Ca2+ and Ag+. Furthermore, under identical conditions, the metal cations cause no change to the fluorescence emission spectra of 1, so probe 1 can respond to hydrazine in the presence of these metal cations (50 equiv.). Similar test results were observed on the selectivity to anion detection (Cl , Br , I , SO42 , SO32 , ClO4 , HCO3 , SCN and HPO42 ) (Fig. S6, ESI†). Thus probe 1 showed excellent selectivity to hydrazine. Most importantly, probe 1 could be applied for the detection of gas-state hydrazine which can further discriminate hydrazine aqueous solutions of different concentrations. To make the detection experiments easy to perform and practical, a TLC plate was used. Prior to detection, a glass TLC plate was firstly immersed into a methanol solution of 1 (5 mM) and dried, then the probe-loaded TLC plate was covered on the top of a jar containing hydrazine solution for 10 min at r.t. before it was ready to observe. As shown in Fig. 3, the change in the color of the fluorescence from colorless to yellow was observed using a hand-held UV lamp with excitation at 365 nm. The gas state hydrazine detection limit of probe 1 is 111.7 mg m 3 which is well below the half lethal dose of hydrazine gas for mice (330 mg m 3).11 Moreover, the fluorescence intensity of the probe on the TLC plate was dependent on the concentration of hydrazine in aqueous solution and was easy to distinguish by naked eyes. Hydrazine in gaseous form often threatens human life, so our designed probe has more application potential. To further demonstrate the application potential of probe 1 in living cells, the probe was applied in Hela cells for fluorescence
This journal is © The Royal Society of Chemistry 2014
View Article Online
Published on 29 November 2013. Downloaded by The University of Manchester Library on 27/10/2014 00:25:30.
ChemComm
Fig. 3 Visual and fluorescence color changes of probe 1 (5.0 mM)-coated TLC plates after exposure to the different concentration of hydrazine aqueous solution. The fluorescence color changes were observed using a hand-held UV lamp with an excitation at 365 nm.
Communication
for the discrimination of different concentrations of gas-state hydrazine with the detection limit of 111.7 mg m 3, with an easy and practical method, which provided a convenient way for hydrazine detection. Finally, the living cell imaging of hydrazine further proved the great potential of the probe for practical utilization. This work is financially supported by the National Natural Science Foundation of China (21236002, 21202097), the National Basic Research Program of China (973 Program, 2010CB126100), the National High Technology Research and Development Program of China (863 Program 2011AA10A207), and the Fundamental Research Funds for the Central Universities.
Notes and references
Fig. 4 Fluorescence images of HeLa cells. Cells were incubated with probe 1 (10 mM) for 30 min (a–c); image of cells after treatment with probe 1 (10 mM) for 30 min and subsequent treatment of the cells with 50 mM hydrazine for 20 min (d–f). (a and d) Bright-field images of the HeLa cells in samples; (b and e) images were taken between 540–580 nm (green); and (c and f) is the overlap of brightfield and fluorescence. Scare bar: 20 mm.
imaging of hydrazine. Hela cells incubated with 1 (10 mM) for 20 min at 37 1C in PBS buffer with 0.5% DMSO showed nearly no intracellular fluorescence. When hydrazine (50 mM) was added and then incubated for further 10 min, a strong fluorescence signal was observed and collected in the green channel from 520 nm to 560 nm with 1/5 s exposure time (Fig. 4). These cell experiments indicated that probe 1 could provide a sensitive and fast response to hydrazine in cells. In summary, we have first developed a selective fluorescent probe 1 for hydrazine detection based on Gabriel synthesis. The probe could selectively react with hydrazine, resulting in an OFF–ON fluorescence signal change at 540 nm and the colour changes from colourless to yellow at room temperature within 2 minutes. The solution detection limit of 1 was found to be 0.3 ppb, which is far below the 10 ppb limit for hydrazine exposure set by the U.S. EPA. Importantly, probe 1 was successfully applied
This journal is © The Royal Society of Chemistry 2014
1 S. D. Zelnick, D. R. Mattie and P. C. Stepaniak, Aviat., Space Environ. Med., 2003, 74, 1285–1291; I. C. Vieira, K. O. Lupetti and O. Fatibello-Filho, Anal. Lett., 2002, 35, 2221–2231. 2 Hydrazine and Its Derivatives, in Kirk-Othmer Encyclopedia of Chemical Technology, ed. J. I. Kroschwitz and A. Seidel, Wiley, New York, 5th edn, 2005, vol. 13, pp. 562–607. 3 S. Garrod, M. E. Bollard, A. W. Nicholls, S. C. Connor, J. Connelly, J. K. Nicholson and E. Holmes, Chem. Res. Toxicol., 2005, 18, 115–122; C. A. Reilly, Chem. Res. Toxicol., 1997, 10, 328–334. 4 Y.-Y. Liu, I. Schmeltz and D. Hoffmann, Anal. Chem., 1974, 46, 885–889; J.-A. Oh, J.-H. Park and H.-S. Shin, Anal. Chim. Acta, 2013, 769, 79–83. 5 A. Umar, M. M. Rahman, S. H. Kim and Y.-B. Hahn, Chem. Commun., 2008, 166–168; J. Liu, Y. Li, J. Jiang and X. Huang, Dalton Trans., 2010, 39, 8693–8697. 6 M. H. Lee, B. Yoon, J. S. Kim and J. L. Sessler, Chem. Sci., 2013, 4, 4121–4126; C. Hu, W. Sun, J. Cao, P. Gao, J. Wang, J. Fan, F. Song, S. Sun and X. Peng, Org. Lett., 2013, 15, 4022–4025; M. G. Choi, J. O. Moon, J. Bae, J. W. Lee and S. K. Chang, Org. Biomol. Chem., 2013, 11, 2961–2965; J. Fan, W. Sun, M. Hu, J. Cao, G. Cheng, H. Dong, K. Song, Y. Liu, S. Sun and X. Peng, Chem. Commun., 2012, 48, 8117–8119; M. G. Choi, J. Hwang, J. O. Moon, J. Sung and S. K. Chang, Org. Lett., 2011, 13, 5260–5263; Y.-D. Lin and T. J. Chow, RSC Adv., 2013; K. Li, H.-R. Xu, K.-K. Yu, J.-T. Hou and X.-Q. Yu, Anal. Methods, 2013, 5, 2653–2656. 7 K. Wang, X. He, X. Yang and H. Shi, Acc. Chem. Res., 2013, 46, 1367–1376; L. Yuan, W. Lin, K. Zheng and S. Zhu, Acc. Chem. Res., 2013, 46, 1462–1473; L. Yuan, W. Lin, K. Zheng, L. He and W. Huang, Chem. Soc. Rev., 2013, 42, 622–661; H. Li, J. Fan and X. Peng, Chem. Soc. Rev., 2013, 42, 7943–7962. 8 M. S. Gibson and R. W. Bradshaw, Angew. Chem., Int. Ed. Engl., 1968, 7, 919–930. 9 H. M. N. H. Irving, H. Freiser and T. S. West, IUPAC Compendium of Analytical Nomenclature, Definitive Rules, Pergamon Press, Oxford, 1981. 10 M. R. Crampton, T. A. Emokpae and C. Isanbor, J. Phys. Org. Chem., 2006, 19, 75–80; M. B. Smith, in March’s Advanced Organic Chemistry, ed. J. March, New York, John Wiley, 5th edn, 2001, p. 860; R. Ormazabal-Toledo, R. Contreras, R. A. Tapia and P. R. Campodonico, Org. Biomol. Chem., 2013, 11, 2302–2309. 11 U.S. Department of Health and Human Services. Registry of Toxic Effects of Chemical Substances (RTECS, online database). National Toxicology Information Program, National Library of Medicine, Bethesda, MD, 1993.
Chem. Commun., 2014, 50, 1485--1487 | 1487
