A fluorescence ratiometric probe 1 for cysteine (Cys) and homocysteine (Hcy) has been rationally constructed based on intramolecular charge transfer (ICT) mechanism. Upon treatment with Cys/Hcy, probe 1 exhibited a fl...A fluorescence ratiometric probe 1 for cysteine (Cys) and homocysteine (Hcy) has been rationally constructed based on intramolecular charge transfer (ICT) mechanism. Upon treatment with Cys/Hcy, probe 1 exhibited a fluorescence ratiometric response, with the emission wavelength displaying a large shift (from 526 nm to 446 nm). When 90 μM Cys were added, the emission ratios (I446/I526) of the probe changed dramatically from 0.01797 to 4.65472. The detection limit was also measured to be 0.18 μM (S/N = 3). The theoretical calculations have confirmed that the ratiometric response of probe 1 to Cys/Hcy is due to the inhibition of ICT process upon the reaction of probe 1 with Cys/Hcy. Furthermore, the fluorescence imaging experiments in living cell demonstrated that probe 1 was favourable for intracellular Cys/Hcy imaging.展开更多
In the present work, Compound 1 has been synthesized as a novel fluorescence ratiometric probe for CN-. Upon treatment with CN-, Probe 1 exhibited a fluorescence ratiometric response, with the emission wavelength shif...In the present work, Compound 1 has been synthesized as a novel fluorescence ratiometric probe for CN-. Upon treatment with CN-, Probe 1 exhibited a fluorescence ratiometric response, with the emission wavelength shift from 570 nm to 608 nm. When 90 μM CN-?was introduced, the emission ratios (I570/I608) of the probe changed dramatically from 0.52156 to 4.21472. The detection limit was also measured to be 0.24 μM (S/N = 3). In addition, Probe 1 had a selective response to CN-, while other anions caused nearly no interference. The sensing reaction product of Probe 1 with CN-?was characterized by 1H NMR spectra and ESI Mass spectrometry. Furthermore, Probe 1 has been successfully applied to detect CN-?in natural water samples. The fluorescence imaging experiments in living cells also demonstrated that Probe 1 could monitor CN-?in biological samples.展开更多
Reduced graphene oxide （RGO） has been covalently functionalized with porphyrin moieties by two methods： A straightforward Prato reaction （i.e. a 1,3-dipolar cycloaddition） with sarcosine and a formyl-containing p...Reduced graphene oxide （RGO） has been covalently functionalized with porphyrin moieties by two methods： A straightforward Prato reaction （i.e. a 1,3-dipolar cycloaddition） with sarcosine and a formyl-containing porphyrin, and a stepwise method that involves a 1,3-dipolar cycloaddition to the RGO surface using 4-hydroxybenzaldehyde, followed by nucleophilic substitution with an appropriate porphyrin. The chemical bonding of porphyrins to the RGO surface has been confirmed by ultraviolet/visible absorption, fluorescence, Fourier-transform infrared, and Raman spectroscopies, X-ray powder diffraction and X-ray photoelectron specfroscop）~ transmission electron and atomic force microscopy, and thermogravimetric analysis; this chemical attachment assures efficient electron/energy transfer between RGO and the porphyrin, and affords improved optical nonlinearities compared to those of the RGO precursor and the pristine porphyrin.展开更多
文摘A fluorescence ratiometric probe 1 for cysteine (Cys) and homocysteine (Hcy) has been rationally constructed based on intramolecular charge transfer (ICT) mechanism. Upon treatment with Cys/Hcy, probe 1 exhibited a fluorescence ratiometric response, with the emission wavelength displaying a large shift (from 526 nm to 446 nm). When 90 μM Cys were added, the emission ratios (I446/I526) of the probe changed dramatically from 0.01797 to 4.65472. The detection limit was also measured to be 0.18 μM (S/N = 3). The theoretical calculations have confirmed that the ratiometric response of probe 1 to Cys/Hcy is due to the inhibition of ICT process upon the reaction of probe 1 with Cys/Hcy. Furthermore, the fluorescence imaging experiments in living cell demonstrated that probe 1 was favourable for intracellular Cys/Hcy imaging.
文摘In the present work, Compound 1 has been synthesized as a novel fluorescence ratiometric probe for CN-. Upon treatment with CN-, Probe 1 exhibited a fluorescence ratiometric response, with the emission wavelength shift from 570 nm to 608 nm. When 90 μM CN-?was introduced, the emission ratios (I570/I608) of the probe changed dramatically from 0.52156 to 4.21472. The detection limit was also measured to be 0.24 μM (S/N = 3). In addition, Probe 1 had a selective response to CN-, while other anions caused nearly no interference. The sensing reaction product of Probe 1 with CN-?was characterized by 1H NMR spectra and ESI Mass spectrometry. Furthermore, Probe 1 has been successfully applied to detect CN-?in natural water samples. The fluorescence imaging experiments in living cells also demonstrated that Probe 1 could monitor CN-?in biological samples.
基金Financial support from the National Natural Science Foundation of China （Nos. 51432006, 50925207 and 51172100）, the Ministry of Science and Technology of China for the International Science Linkages Program （Nos. 2009DFA50620 and 2011DFG52970）, the Ministry of Education of China for the Changjiang Innovation Research Team （No. IRT1064）, the Ministry of Educa- tion and the State Administration of Foreign Experts Affairs for the 111 Project （No. B13025）, and Jiangsu Innovation Research Team are gratefully acknowledged. M. G. H and M. P. C. thank the Australian Research Council （ARC） for support.
文摘Reduced graphene oxide （RGO） has been covalently functionalized with porphyrin moieties by two methods： A straightforward Prato reaction （i.e. a 1,3-dipolar cycloaddition） with sarcosine and a formyl-containing porphyrin, and a stepwise method that involves a 1,3-dipolar cycloaddition to the RGO surface using 4-hydroxybenzaldehyde, followed by nucleophilic substitution with an appropriate porphyrin. The chemical bonding of porphyrins to the RGO surface has been confirmed by ultraviolet/visible absorption, fluorescence, Fourier-transform infrared, and Raman spectroscopies, X-ray powder diffraction and X-ray photoelectron specfroscop）~ transmission electron and atomic force microscopy, and thermogravimetric analysis; this chemical attachment assures efficient electron/energy transfer between RGO and the porphyrin, and affords improved optical nonlinearities compared to those of the RGO precursor and the pristine porphyrin.
