A highly sensitive SPE-liquid/liquid extraction RPLC method has been developed for the analysis of 6β-hydroxycortisol and cortisol in the urine of cancer patients. Methods: After SPE column purification and liquid-l...A highly sensitive SPE-liquid/liquid extraction RPLC method has been developed for the analysis of 6β-hydroxycortisol and cortisol in the urine of cancer patients. Methods: After SPE column purification and liquid-liquid extraction, the sample test solutions were analyzed with RPLC using a C18 analytical column. This improved analytical method has been validated for linearity, accuracy (recovery from urine), repeatability (within-day and between-day precision), specificity, sensitivity, and stability. This SPE-liquid/liquid extraction-RPLC is rapid, simple, accurate and reproducible. The technique is particularly useful for monitoring the CYP3A activity of cancer patients in clinical settings. The results are expressed as the ratio of 6β-hydroxycortisol to cortisol. Results: The CYP3A activity from a total of 153 samples was measured using this improved method. Considerable variation in the CYP3A activity of different cancer patients has been documented. Thus, personalized medical treatment based on the individual metabolic enzyme activity level is necessary. Conclusion: This new analytical method facilitates such individualized medical treatments.展开更多
Phytoremediation effectiveness and remediation costs are driving factors of this project. Full utilization of plant resources after their being used for phytoremediation is an unsolved problem. GC/MS technique was use...Phytoremediation effectiveness and remediation costs are driving factors of this project. Full utilization of plant resources after their being used for phytoremediation is an unsolved problem. GC/MS technique was used to investigate the volatiles of the flowers from Elsholtzia argyi (PFE1: Purple Flower Elsholtzia) and their variation (WFE: White Flower Elsholtzia),naturally growing in Pb/Zn mined area, and Elsholtzia argyi (PFE2: Purple Flower Elsholtzia), naturally growing in Jiuxi uncontaminated agriculture soil. Seventeen compounds constituting 86.88% of total essential oils were identified in PFE1, with 2,6-octadienoic acid,3,7-dimethyl-methyl ester being the main constituent (63.30%). Sixteen compounds accounting for 95.32% of total essential oils were identified in WFE, with caryophyllene being the main component (55.02%). Compared to PFE1, PFE2 contained lower level of 2,6-octadienoic acid,3,7-dimethyl-methyl ester (31.76%), which was the main constituent in the total essential oils of PFE2. Caryophyllene is the main ingredient of flavor. Elsholtzia ketone was identified in all the three Elsholtzia plants. It can be concluded that the selected Elsholtzia argyi plants can be exploited on their versatile uses as fragrances and antiseptics due to the perfume ingredient and antibacterial components existing in their essential oils.展开更多
Based on chromatographic theory, the moment method and the time-domain fitting analysis were applied to measure and evaluate the adsorption equilibrium constant and mass transfer properties (axial dispersion coefficie...Based on chromatographic theory, the moment method and the time-domain fitting analysis were applied to measure and evaluate the adsorption equilibrium constant and mass transfer properties (axial dispersion coefficient and effective intra-particle diffusivity) for toluene and p-dichlorobenzene on silica gel adsorbent in the subcritical and supercritical CO2. An apparatus based on supercritical fluid chromatography was established and the experiments were performed at temperatures of 298.15-318.15 K and pressures of 7.5-17.8 MPa. The two methods have been compared. The results show that for the systems studied here the moment method can give reasonable values for both adsorption equilibrium constant and mass transfer properties, but the time-domain analysis only can obtain the adsorption equilibrium constant. The dependence of adsorption equilibrium constant and mass transfer properties on temperature and pressure was investigated.展开更多
Ion-induced charge-transfer states in conjugated polyelectrolytes were experimentally investigated by Justin M.Hodgkiss and his co-workers [J Am Chem Soc,2009,131(25):8913].In this work,charged and neutral conjugated ...Ion-induced charge-transfer states in conjugated polyelectrolytes were experimentally investigated by Justin M.Hodgkiss and his co-workers [J Am Chem Soc,2009,131(25):8913].In this work,charged and neutral conjugated polyelectrolytes were further studied with quantum chemistry methods.The calculation result shows that the absorption spectra are roughly in visible and ultraviolet light regions,and the two absorption peaks are located in the wavelength span 300-400 nm for charged polyelectrolytes.However,in neutral conjugated polyelectrolytes,the peaks of the absorption spectra showed a blue shift compared with those of the charged polyelectrolytes.Charge transfer (CT) properties of the studied compounds were also investigated with both the three-dimensional real-space analysis method of transition and charge difference densities,and the two-dimensional real-space analysis method of transition density matrices based on the simulated absorption spectra.The calculation results revealed the charge transfer in conjugated polyelectrolytes on the excitation states.展开更多
In this article, we present a facile, direct, synthetic approach of preparing monodisperse [Au2s(SePh)ls]- nanoclusters in high yield. In this synthetic approach, two-phase Brust-Schiffrin method is used. Both PhSeH...In this article, we present a facile, direct, synthetic approach of preparing monodisperse [Au2s(SePh)ls]- nanoclusters in high yield. In this synthetic approach, two-phase Brust-Schiffrin method is used. Both PhSeH and NaBH4 should be added drop-wise to the solution of Au (III) at the same time. The formula and molecular purity of [Au25(SePh)ls] TOA+ clusters are characterized by MALDI-TOF mass spectrometry, NMR and TGA analysis. Furthermore, some critical parameters to obtain pure [Au25(SePh)18]-TOA+ are identified, including the NaBH4-to-Au ratio, the selenolate-to-Au ratio and the temperature. The facile, direct, high yield synthetic method can be widely applied in the theoretical research of Au clusters protected by selenol.展开更多
基金supported by the Shanghai Pharmaceutical Association
文摘A highly sensitive SPE-liquid/liquid extraction RPLC method has been developed for the analysis of 6β-hydroxycortisol and cortisol in the urine of cancer patients. Methods: After SPE column purification and liquid-liquid extraction, the sample test solutions were analyzed with RPLC using a C18 analytical column. This improved analytical method has been validated for linearity, accuracy (recovery from urine), repeatability (within-day and between-day precision), specificity, sensitivity, and stability. This SPE-liquid/liquid extraction-RPLC is rapid, simple, accurate and reproducible. The technique is particularly useful for monitoring the CYP3A activity of cancer patients in clinical settings. The results are expressed as the ratio of 6β-hydroxycortisol to cortisol. Results: The CYP3A activity from a total of 153 samples was measured using this improved method. Considerable variation in the CYP3A activity of different cancer patients has been documented. Thus, personalized medical treatment based on the individual metabolic enzyme activity level is necessary. Conclusion: This new analytical method facilitates such individualized medical treatments.
文摘Phytoremediation effectiveness and remediation costs are driving factors of this project. Full utilization of plant resources after their being used for phytoremediation is an unsolved problem. GC/MS technique was used to investigate the volatiles of the flowers from Elsholtzia argyi (PFE1: Purple Flower Elsholtzia) and their variation (WFE: White Flower Elsholtzia),naturally growing in Pb/Zn mined area, and Elsholtzia argyi (PFE2: Purple Flower Elsholtzia), naturally growing in Jiuxi uncontaminated agriculture soil. Seventeen compounds constituting 86.88% of total essential oils were identified in PFE1, with 2,6-octadienoic acid,3,7-dimethyl-methyl ester being the main constituent (63.30%). Sixteen compounds accounting for 95.32% of total essential oils were identified in WFE, with caryophyllene being the main component (55.02%). Compared to PFE1, PFE2 contained lower level of 2,6-octadienoic acid,3,7-dimethyl-methyl ester (31.76%), which was the main constituent in the total essential oils of PFE2. Caryophyllene is the main ingredient of flavor. Elsholtzia ketone was identified in all the three Elsholtzia plants. It can be concluded that the selected Elsholtzia argyi plants can be exploited on their versatile uses as fragrances and antiseptics due to the perfume ingredient and antibacterial components existing in their essential oils.
基金Supported by research grant 02KJB530002 from Jiangsu Provincial Committee of Education.
文摘Based on chromatographic theory, the moment method and the time-domain fitting analysis were applied to measure and evaluate the adsorption equilibrium constant and mass transfer properties (axial dispersion coefficient and effective intra-particle diffusivity) for toluene and p-dichlorobenzene on silica gel adsorbent in the subcritical and supercritical CO2. An apparatus based on supercritical fluid chromatography was established and the experiments were performed at temperatures of 298.15-318.15 K and pressures of 7.5-17.8 MPa. The two methods have been compared. The results show that for the systems studied here the moment method can give reasonable values for both adsorption equilibrium constant and mass transfer properties, but the time-domain analysis only can obtain the adsorption equilibrium constant. The dependence of adsorption equilibrium constant and mass transfer properties on temperature and pressure was investigated.
基金supported by the National Natural Science Foundation of China (Grant Nos.11074210 and 20703032)the National Basic Research Project of China (Grant No.2009CB930703)
文摘Ion-induced charge-transfer states in conjugated polyelectrolytes were experimentally investigated by Justin M.Hodgkiss and his co-workers [J Am Chem Soc,2009,131(25):8913].In this work,charged and neutral conjugated polyelectrolytes were further studied with quantum chemistry methods.The calculation result shows that the absorption spectra are roughly in visible and ultraviolet light regions,and the two absorption peaks are located in the wavelength span 300-400 nm for charged polyelectrolytes.However,in neutral conjugated polyelectrolytes,the peaks of the absorption spectra showed a blue shift compared with those of the charged polyelectrolytes.Charge transfer (CT) properties of the studied compounds were also investigated with both the three-dimensional real-space analysis method of transition and charge difference densities,and the two-dimensional real-space analysis method of transition density matrices based on the simulated absorption spectra.The calculation results revealed the charge transfer in conjugated polyelectrolytes on the excitation states.
基金the financial support by the National Natural Science Foundation of China (20871112, 21072001, 21372006)Changjiang Scholars Program+1 种基金the Scientific Research Foundation for Returning Overseas Chinese Scholars, State Education Ministry, Ministry of Human Resources and Social Security, Anhui Province International Scientific and Technological Cooperation Project211 Project of Anhui University
文摘In this article, we present a facile, direct, synthetic approach of preparing monodisperse [Au2s(SePh)ls]- nanoclusters in high yield. In this synthetic approach, two-phase Brust-Schiffrin method is used. Both PhSeH and NaBH4 should be added drop-wise to the solution of Au (III) at the same time. The formula and molecular purity of [Au25(SePh)ls] TOA+ clusters are characterized by MALDI-TOF mass spectrometry, NMR and TGA analysis. Furthermore, some critical parameters to obtain pure [Au25(SePh)18]-TOA+ are identified, including the NaBH4-to-Au ratio, the selenolate-to-Au ratio and the temperature. The facile, direct, high yield synthetic method can be widely applied in the theoretical research of Au clusters protected by selenol.