The interactions of antibiotic with living cells were studied by lectin conjugated gold nanoparticles（GNPs） based colorimetric assay. Because of the high affinity of lectin for saccharides, the lectin conjugated GNP...The interactions of antibiotic with living cells were studied by lectin conjugated gold nanoparticles（GNPs） based colorimetric assay. Because of the high affinity of lectin for saccharides, the lectin conjugated GNPs are able to employ as indicators for monitoring the antibiotic induced changes of glycosyl complexes. The interactions of a well known antibiotic, tunicamycin, with two different cell lines, HeLa and SHG-44, were selected to establish this assay. In the presence of tunicamycin, the dose- and time-dependence on the decreasing of binding affinity of lectin conjugated GNPs with living cells were demonstrated by conventional microscopic and UV-Vis spectroscopic studies. The experimental result demonstrates that our approach can be used to identify antibiotic induced expression difference of glycosyl complexes on different cellular surfaces and determine drug activity quantitatively. For further confirming the capability of the GNP-based assay, the system was also studied by confocal laser scanning microscopy（CLSM） and classic flow cytometry（FCM） assay, and satisfactory results were obtained.展开更多
A general functionalization strategy was reported,which enables one to conjugate saccharide（SA） on gold nanoparticle（GNP） surface without affecting SA properties.First,disulfide phenylboronic acid（Bor） functiona...A general functionalization strategy was reported,which enables one to conjugate saccharide（SA） on gold nanoparticle（GNP） surface without affecting SA properties.First,disulfide phenylboronic acid（Bor） functionalized GNPs（Bor@GNPs） were synthesized by the reaction of citrate stabilized GNPs of 13 nm in diameter with the mixture of Bor and pentapeptide（Cys-Ala-Leu-Asn-Asn,CALNN）.Subsequently,the SA-GNP conjugates（SA@GNPs） were prepared by coupling SA to the GNP surface via the reaction of phenylboronic acid（PBA） with the cis-diol configuration in SA.The interactions of three SA@GNPs with three lectins have been analyzed by UV-visible spectroscopic and transmission electronic microscopic（TEM） techniques,respectively.The experimental results demonstrate that SA@GNPs can efficiently bind to lectins and show a great promise as optical probes for monitoring specific affinities of lectins for SA,and detecting lectins with high sensitivity.展开更多
The authors presented a simple colorimetric assay for the detection of toxic heavy metal lead（Ⅱ） ion（Pb2＋） Pentapeptide, cysteine-alanine-leacine-asparagine-asparagine（CALNN）, functionalized gold nanoparticles...The authors presented a simple colorimetric assay for the detection of toxic heavy metal lead（Ⅱ） ion（Pb2＋） Pentapeptide, cysteine-alanine-leacine-asparagine-asparagine（CALNN）, functionalized gold nanoparticles（GNPs） were aggregated in the presence of the divalent metal ion in solution by an ion-templated chelation process, which caused an easily measurable change in the absorption spectrum of the particles. Typically, mono-dispersing GNPs exhibit an absorption band at 522 nm, corresponding to a red color solution, while aggregated GNPs have it at longer wavelengths, corresponding to a purple or blue color solution. The chelation/aggregation process is reversible via the addition of a strong metal ion chelator such as EDTA. Highly selective and sensitive detection of Pb^2＋ in aqueous solution is thus provided. A detection limit of 0.1 μmol/L of Pb^2＋ was demonstrated.展开更多
We present a newly designed colorimetric sensor sensitive to pH value based on a gold nanocomposite composed of gold nanoparticles and pH-sensitive polymer{dodecylthioether end functionalized poly[2-（diethylamino） e...We present a newly designed colorimetric sensor sensitive to pH value based on a gold nanocomposite composed of gold nanoparticles and pH-sensitive polymer{dodecylthioether end functionalized poly[2-（diethylamino） ethyl methacrylate], poly（DEAEMA）-DDT}. We have shown that this design can produce stable GNP precipitate under weakly basic condition（pH=7.5） and this precipitate can be dispersed in acidic solution（pH=4.0）, due to the 2-（diethylamino） ethyl methacrylate protonated by H＋. The precipitation-dispersion process is reversible and accompanied by distinct color change that are clearly visible to the naked eye. This development may have application in the controlled fabrication of reversible pH-sensitive nanostructures and/or devices.展开更多
Backgroud Fluorine-18-fluorodeoxyglucose （18F-FDG） positron emission tomography imaging can be used to assess the treatment efficacy of chemotherapy and prognosis.The aim of this study was to determine the uptake ra...Backgroud Fluorine-18-fluorodeoxyglucose （18F-FDG） positron emission tomography imaging can be used to assess the treatment efficacy of chemotherapy and prognosis.The aim of this study was to determine the uptake rate of 18F-FDG in colon cancer HCT-116 cells,and to evaluate the treatment efficacy of chemotherapy,hyperthermia and thermo-chemotherapy through the uptake inhibition rate of 18F-FDG.Methods The uptake rate of 18F-FDG in HCT-116 ceils was determined at various experimental conditions.The inhibition rate of cell growth,uptake rate of 18F-FDG and uptake inhibition rate of l8F-FDG in HCT-116 cells treated with 5-fluorouracil （5-FU） at various concentrations were determined.In HCT-116 cells subjected to chemotherapy （5-FU,100 μg/ml）,hyperthermia （43℃,40 minutes） and thermo-chemotherapy for 24 hours,the inhibition rate of cell growth and uptake inhibition rate of 18F-FDG were determined; early apoptosis,the morphology and ultrastructure of HCT-116 cells were examined; and the contents of glucose and lactate dehydrogenase （LDH） in the cell culture medium of HCT-116 cells were determined.One-way analysis of variance （ANOVA） and correlation analyses were conducted by using SPSS 16.0 software.Results The uptake rate of 18F-FDG in HCT-116 cells was （44.25±2.19）%.Under the condition of adding 5-FU at various concentrations for 24 hours,the uptake rate of 18F-FDG was negatively correlated with 5-FU dosage （r=-0.879,P 〈0.01）; the inhibition rate of cell growth revealed a positive correlation with the uptake inhibition rate of 18F-FDG （r=0.831,P 〈0.01）.In HCT-116 cells subjected to hyperthermia,chemotherapy,and thermo-chemotherapy for 24 hours,the uptake inhibition rates of 18F-FDG were （12.94±2.80）%,（28.25±4.59）%,and （21.60±3.68）%,respectively.The early apoptotic rates of HCT-116 cells were （9.80±0.16）%,（19.80±2.40）%,and （15.70±1.80）%,respectively.Moreover,the contents of glucose and LDH in cell culture medium of HCT-116 cells after treatments were higher than those before treatment.Conclusion The uptake inhibition rate of 18F-FDG can be used for early evaluation of hyperthermia and 5-FU treatment efficacy on cancer cells although hyperthermia （43℃,40 minutes） does not reveal the synergistic effect on 5-FU at the low dosage.展开更多
基金Supported by the National Natural Science Foundation of China(No.20875087)the Fund of Chinese Academy of Sciences (No.KJCX2-YW-H11)
文摘The interactions of antibiotic with living cells were studied by lectin conjugated gold nanoparticles（GNPs） based colorimetric assay. Because of the high affinity of lectin for saccharides, the lectin conjugated GNPs are able to employ as indicators for monitoring the antibiotic induced changes of glycosyl complexes. The interactions of a well known antibiotic, tunicamycin, with two different cell lines, HeLa and SHG-44, were selected to establish this assay. In the presence of tunicamycin, the dose- and time-dependence on the decreasing of binding affinity of lectin conjugated GNPs with living cells were demonstrated by conventional microscopic and UV-Vis spectroscopic studies. The experimental result demonstrates that our approach can be used to identify antibiotic induced expression difference of glycosyl complexes on different cellular surfaces and determine drug activity quantitatively. For further confirming the capability of the GNP-based assay, the system was also studied by confocal laser scanning microscopy（CLSM） and classic flow cytometry（FCM） assay, and satisfactory results were obtained.
基金Supported by the National Basic Research Program of China(No.2011CB935800)the Project of the Jilin Provincial Science and Technology Department,China(No.20100701)
文摘A general functionalization strategy was reported,which enables one to conjugate saccharide（SA） on gold nanoparticle（GNP） surface without affecting SA properties.First,disulfide phenylboronic acid（Bor） functionalized GNPs（Bor@GNPs） were synthesized by the reaction of citrate stabilized GNPs of 13 nm in diameter with the mixture of Bor and pentapeptide（Cys-Ala-Leu-Asn-Asn,CALNN）.Subsequently,the SA-GNP conjugates（SA@GNPs） were prepared by coupling SA to the GNP surface via the reaction of phenylboronic acid（PBA） with the cis-diol configuration in SA.The interactions of three SA@GNPs with three lectins have been analyzed by UV-visible spectroscopic and transmission electronic microscopic（TEM） techniques,respectively.The experimental results demonstrate that SA@GNPs can efficiently bind to lectins and show a great promise as optical probes for monitoring specific affinities of lectins for SA,and detecting lectins with high sensitivity.
基金Supported by the National Natural Science Foundation of China(No.20675080)the Program of Chinese Academy of Sciences Hundred Talents(No.KJCX2-YW-H11)
文摘The authors presented a simple colorimetric assay for the detection of toxic heavy metal lead（Ⅱ） ion（Pb2＋） Pentapeptide, cysteine-alanine-leacine-asparagine-asparagine（CALNN）, functionalized gold nanoparticles（GNPs） were aggregated in the presence of the divalent metal ion in solution by an ion-templated chelation process, which caused an easily measurable change in the absorption spectrum of the particles. Typically, mono-dispersing GNPs exhibit an absorption band at 522 nm, corresponding to a red color solution, while aggregated GNPs have it at longer wavelengths, corresponding to a purple or blue color solution. The chelation/aggregation process is reversible via the addition of a strong metal ion chelator such as EDTA. Highly selective and sensitive detection of Pb^2＋ in aqueous solution is thus provided. A detection limit of 0.1 μmol/L of Pb^2＋ was demonstrated.
基金the National Natural Science Foundation of China(No.20675080)Chinese Academy of Sciences (No.KJCX2-YW-H11).
文摘We present a newly designed colorimetric sensor sensitive to pH value based on a gold nanocomposite composed of gold nanoparticles and pH-sensitive polymer{dodecylthioether end functionalized poly[2-（diethylamino） ethyl methacrylate], poly（DEAEMA）-DDT}. We have shown that this design can produce stable GNP precipitate under weakly basic condition（pH=7.5） and this precipitate can be dispersed in acidic solution（pH=4.0）, due to the 2-（diethylamino） ethyl methacrylate protonated by H＋. The precipitation-dispersion process is reversible and accompanied by distinct color change that are clearly visible to the naked eye. This development may have application in the controlled fabrication of reversible pH-sensitive nanostructures and/or devices.
文摘Backgroud Fluorine-18-fluorodeoxyglucose （18F-FDG） positron emission tomography imaging can be used to assess the treatment efficacy of chemotherapy and prognosis.The aim of this study was to determine the uptake rate of 18F-FDG in colon cancer HCT-116 cells,and to evaluate the treatment efficacy of chemotherapy,hyperthermia and thermo-chemotherapy through the uptake inhibition rate of 18F-FDG.Methods The uptake rate of 18F-FDG in HCT-116 ceils was determined at various experimental conditions.The inhibition rate of cell growth,uptake rate of 18F-FDG and uptake inhibition rate of l8F-FDG in HCT-116 cells treated with 5-fluorouracil （5-FU） at various concentrations were determined.In HCT-116 cells subjected to chemotherapy （5-FU,100 μg/ml）,hyperthermia （43℃,40 minutes） and thermo-chemotherapy for 24 hours,the inhibition rate of cell growth and uptake inhibition rate of 18F-FDG were determined; early apoptosis,the morphology and ultrastructure of HCT-116 cells were examined; and the contents of glucose and lactate dehydrogenase （LDH） in the cell culture medium of HCT-116 cells were determined.One-way analysis of variance （ANOVA） and correlation analyses were conducted by using SPSS 16.0 software.Results The uptake rate of 18F-FDG in HCT-116 cells was （44.25±2.19）%.Under the condition of adding 5-FU at various concentrations for 24 hours,the uptake rate of 18F-FDG was negatively correlated with 5-FU dosage （r=-0.879,P 〈0.01）; the inhibition rate of cell growth revealed a positive correlation with the uptake inhibition rate of 18F-FDG （r=0.831,P 〈0.01）.In HCT-116 cells subjected to hyperthermia,chemotherapy,and thermo-chemotherapy for 24 hours,the uptake inhibition rates of 18F-FDG were （12.94±2.80）%,（28.25±4.59）%,and （21.60±3.68）%,respectively.The early apoptotic rates of HCT-116 cells were （9.80±0.16）%,（19.80±2.40）%,and （15.70±1.80）%,respectively.Moreover,the contents of glucose and LDH in cell culture medium of HCT-116 cells after treatments were higher than those before treatment.Conclusion The uptake inhibition rate of 18F-FDG can be used for early evaluation of hyperthermia and 5-FU treatment efficacy on cancer cells although hyperthermia （43℃,40 minutes） does not reveal the synergistic effect on 5-FU at the low dosage.
