The mercury species in the ocean(MeHg,Hg^(2+))will be enriched in marine organisms and threaten human health through the food chain.While the excessive H_(2)O_(2)in the metabolic process will produce hydroxyl radicals...The mercury species in the ocean(MeHg,Hg^(2+))will be enriched in marine organisms and threaten human health through the food chain.While the excessive H_(2)O_(2)in the metabolic process will produce hydroxyl radicals and accelerate the aging of human cells,causing a series of diseases.Hence,the cost-effective and rapid detection of mercury and H_(2)O_(2)is of urgent requirement and significance.Here,we synthesized emerging graphitic carbon nitride quantum dots(g-CNQDs)with high fluorescence quantum yield(FLQY)of 42.69%via a bottom-up strategy by a facile one-step hydrothermal method.The g-CNQDs can detect the H_(2)O_(2)and Hg^(2+)through the fluorescence quenching effect between g-CNQDs and detected substances.With the presence of KI,g-CNQDs show concentration-dependent fluorescence toward H_(2)O_(2),with a wide detection range of 1–1000μmolL^(-1)and a low detection limit of 0.23μmolL^(-1).The g-CNQDs also show sensitivity toward Hg^(2+)with a detection range of 0–0.1μmolL^(-1)and a detection limit of 0.038μmolL^(-1).This dual-function detection of g-CNQDs has better practical application capability compared to other quantum dot detection.This study may provide a new strategy for g-CNQDs preparation and construct a fluorescence probe that can be used in various systems involving H_(2)O_(2)and Hg^(2+),providing better support for future bifunctional or multifunction studies.展开更多
We have developed a simple method for the preparation of highly fluorescent and stable, water-soluble CdTe quantum dots in sol-gel-derived composite silica spheres which were coated with calix[6]arene. The resulting n...We have developed a simple method for the preparation of highly fluorescent and stable, water-soluble CdTe quantum dots in sol-gel-derived composite silica spheres which were coated with calix[6]arene. The resulting nanoparticles (NPs) were characterized in terms of UV, fluorescence and FT-IR spectroscopy and TEM. The results show that the new NPs display more intense fluorescence intensity and are more stable than its precursors of the type SiO2/CdTe. Under the optimum, the novel NPs exhibit a higher selectivity and ultrasensitive fluorescence probes for the determination of gly-phosate over other pesticides, the fluorescence intensity increase with the concentration of glyphosate in the range from 1.0 to 25.0 nmol/L and the detection limit is low to 0.0725 nmol/L. A mechanism is suggested to explain the inclusion process by a Langmuir binding isotherm.展开更多
Three sulfhydryl-reactive fluorescent probes, which contain 2-（1H-benzoimidazol-2-yl）-phenol and maleimide group, were synthesized and their structures were characterized by IR and ^1H NMR. Their photo-physical prop...Three sulfhydryl-reactive fluorescent probes, which contain 2-（1H-benzoimidazol-2-yl）-phenol and maleimide group, were synthesized and their structures were characterized by IR and ^1H NMR. Their photo-physical properties and the specificity to sulfhydryl group in the 2-mercapto-ethanol as well as the L-cysteine adducts were indicated by fluorescence intensity. Preliminary tests revealed that the probes could react selectively with the cysteine molecules, suggesting that these probes might be generally useful in biomedical researches.展开更多
A new near-infrared fluorophore 2-(2-Aminoethyl) pyridine-tricarbocyanine (1) was rationally designed and synthe-sized as a fluorescent probe for detection of Cu2+ with high selectivity. The response of Probe 1 is bas...A new near-infrared fluorophore 2-(2-Aminoethyl) pyridine-tricarbocyanine (1) was rationally designed and synthe-sized as a fluorescent probe for detection of Cu2+ with high selectivity. The response of Probe 1 is based on the fluorescence quenching upon binding to Cu2+. The sensing performance of the proposed Cu2+-sensitive Probe 1 was then investigated. The probe can be applied to the quantification detection of Cu2+ with a linear concentration range covering from 4.8 × 10-7 to 1.6 × 10-4 mol/L and a detection limit of 9.3 × 10-8 mol/L. The experimental results showed that the response of 1 to Cu2+ was independent of pH in medium condition (pH 6.0-8.0), and exhibited excellent selectivity towards Cu2+ over other common metal cations.展开更多
The global pandemic caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)virus has necessitated rapid,easy-to-use,and accurate diagnostic methods to monitor the virus infection.Herein,a ratiometric flu...The global pandemic caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)virus has necessitated rapid,easy-to-use,and accurate diagnostic methods to monitor the virus infection.Herein,a ratiometric fluorescence enzyme-linked immunosorbent assay(ELISA)was developed using Si-fluorescein isothiocyanate nanoparticles(FITC NPs)for detecting SARSCoV-2 nucleocapsid(N)protein.Si-FITC NPs were prepared by a one-pot hydrothermal method using 3-aminopropyl triethoxysilane(APTES)-FITC as the Si source.This method did not need post-modification and avoided the reduction in quantum yield and stability.The p-nitrophenyl(pNP)produced by the alkaline phosphatase(ALP)-mediated hydrolysis of pnitrophenyl phosphate(pNPP)could quench Si fluorescence in Si-FITC NPs via the inner filter effect.In ELISA,an immunocomplex was formed by the recognition of capture antibody/N protein/reporter antibody.ALP-linked secondary antibody bound to the reporter antibody and induced pNPP hydrolysis to specifically quench Si fluorescence in Si-FITC NPs.The change in fluorescence intensity ratio could be used for detecting N protein,with a wide linearity range(0.01-10.0 and 50-300 ng/mL)and low detection limit(0.002 ng/mL).The concentration of spiked SARS-CoV-2 N protein could be determined accurately in human serum.Moreover,this proposed method can accurately distinguish coronavirus disease 2019(COVID-19)and non-COVID-19 patient samples.Therefore,this simple,sensitive,and accurate method can be applied for the early diagnosis of SARS-CoV-2 virus infection.展开更多
基金support from the Natural Science Foundation of Shandong Province(No.ZR2021 MB075)National Natural Science Foundation of China(No.51602297)the Opening Fund of State Key Laboratory of High-Efficiency Utilization of Coal and Green Chemical Engineering(No.2021-K53).
文摘The mercury species in the ocean(MeHg,Hg^(2+))will be enriched in marine organisms and threaten human health through the food chain.While the excessive H_(2)O_(2)in the metabolic process will produce hydroxyl radicals and accelerate the aging of human cells,causing a series of diseases.Hence,the cost-effective and rapid detection of mercury and H_(2)O_(2)is of urgent requirement and significance.Here,we synthesized emerging graphitic carbon nitride quantum dots(g-CNQDs)with high fluorescence quantum yield(FLQY)of 42.69%via a bottom-up strategy by a facile one-step hydrothermal method.The g-CNQDs can detect the H_(2)O_(2)and Hg^(2+)through the fluorescence quenching effect between g-CNQDs and detected substances.With the presence of KI,g-CNQDs show concentration-dependent fluorescence toward H_(2)O_(2),with a wide detection range of 1–1000μmolL^(-1)and a low detection limit of 0.23μmolL^(-1).The g-CNQDs also show sensitivity toward Hg^(2+)with a detection range of 0–0.1μmolL^(-1)and a detection limit of 0.038μmolL^(-1).This dual-function detection of g-CNQDs has better practical application capability compared to other quantum dot detection.This study may provide a new strategy for g-CNQDs preparation and construct a fluorescence probe that can be used in various systems involving H_(2)O_(2)and Hg^(2+),providing better support for future bifunctional or multifunction studies.
文摘We have developed a simple method for the preparation of highly fluorescent and stable, water-soluble CdTe quantum dots in sol-gel-derived composite silica spheres which were coated with calix[6]arene. The resulting nanoparticles (NPs) were characterized in terms of UV, fluorescence and FT-IR spectroscopy and TEM. The results show that the new NPs display more intense fluorescence intensity and are more stable than its precursors of the type SiO2/CdTe. Under the optimum, the novel NPs exhibit a higher selectivity and ultrasensitive fluorescence probes for the determination of gly-phosate over other pesticides, the fluorescence intensity increase with the concentration of glyphosate in the range from 1.0 to 25.0 nmol/L and the detection limit is low to 0.0725 nmol/L. A mechanism is suggested to explain the inclusion process by a Langmuir binding isotherm.
基金Supported by the National Natural Science Foundation of China(No.20771082)the Natural Science Foundation of Tianjin Municipality, China(No.09JCYBJC05800)the Educational Commission of Tianjin Municipality, China (No.20080509)
文摘Three sulfhydryl-reactive fluorescent probes, which contain 2-（1H-benzoimidazol-2-yl）-phenol and maleimide group, were synthesized and their structures were characterized by IR and ^1H NMR. Their photo-physical properties and the specificity to sulfhydryl group in the 2-mercapto-ethanol as well as the L-cysteine adducts were indicated by fluorescence intensity. Preliminary tests revealed that the probes could react selectively with the cysteine molecules, suggesting that these probes might be generally useful in biomedical researches.
文摘A new near-infrared fluorophore 2-(2-Aminoethyl) pyridine-tricarbocyanine (1) was rationally designed and synthe-sized as a fluorescent probe for detection of Cu2+ with high selectivity. The response of Probe 1 is based on the fluorescence quenching upon binding to Cu2+. The sensing performance of the proposed Cu2+-sensitive Probe 1 was then investigated. The probe can be applied to the quantification detection of Cu2+ with a linear concentration range covering from 4.8 × 10-7 to 1.6 × 10-4 mol/L and a detection limit of 9.3 × 10-8 mol/L. The experimental results showed that the response of 1 to Cu2+ was independent of pH in medium condition (pH 6.0-8.0), and exhibited excellent selectivity towards Cu2+ over other common metal cations.
基金supported by the National Key Research and Development Program of China(No.2021YFA0910900)the National Natural Science Foundation(No.22104147)+4 种基金Youth Innovation Promotion Association CAS(No.2021359)the Natural Science Foundation of Guangdong(Nos.2018B030306046 and 2020A1515111130)Guangdong Provincial Key Laboratory of Synthetic Genomics(No.2019B030301006)Shenzhen Science and Technology Program(No.KQTD20180413181837372)Shenzhen Outstanding Talents Training Fund.
文摘The global pandemic caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)virus has necessitated rapid,easy-to-use,and accurate diagnostic methods to monitor the virus infection.Herein,a ratiometric fluorescence enzyme-linked immunosorbent assay(ELISA)was developed using Si-fluorescein isothiocyanate nanoparticles(FITC NPs)for detecting SARSCoV-2 nucleocapsid(N)protein.Si-FITC NPs were prepared by a one-pot hydrothermal method using 3-aminopropyl triethoxysilane(APTES)-FITC as the Si source.This method did not need post-modification and avoided the reduction in quantum yield and stability.The p-nitrophenyl(pNP)produced by the alkaline phosphatase(ALP)-mediated hydrolysis of pnitrophenyl phosphate(pNPP)could quench Si fluorescence in Si-FITC NPs via the inner filter effect.In ELISA,an immunocomplex was formed by the recognition of capture antibody/N protein/reporter antibody.ALP-linked secondary antibody bound to the reporter antibody and induced pNPP hydrolysis to specifically quench Si fluorescence in Si-FITC NPs.The change in fluorescence intensity ratio could be used for detecting N protein,with a wide linearity range(0.01-10.0 and 50-300 ng/mL)and low detection limit(0.002 ng/mL).The concentration of spiked SARS-CoV-2 N protein could be determined accurately in human serum.Moreover,this proposed method can accurately distinguish coronavirus disease 2019(COVID-19)and non-COVID-19 patient samples.Therefore,this simple,sensitive,and accurate method can be applied for the early diagnosis of SARS-CoV-2 virus infection.
