Sc and Zn were introduced into O3-NaMn_(0.5)Ni_(0.5)O_(2)(NaMN)using the combination of solution combustion and solid-state method.The effect of Sc and Zn dual-substitution on Na^(+) diffusion dynamics and structural ...Sc and Zn were introduced into O3-NaMn_(0.5)Ni_(0.5)O_(2)(NaMN)using the combination of solution combustion and solid-state method.The effect of Sc and Zn dual-substitution on Na^(+) diffusion dynamics and structural stability of NaMN was investigated.The physicochemical characterizations suggest that the introduction of Sc and Zn broaden Na^(+) diffusion channels and weaken the Na—O bonds,thereby facilitating the diffusion of sodium ions.Simulations indicate that the Sc and Zn dual-substitution decreases the diffusion barrier of Na-ions and improves the conductivity of the material.The dual-substituted NaMn_(0.5)Ni_(0.4)Sc_(0.04)Zn_(0.04)O_(2)(Na MNSZ44)cathode delivers impressive cycle stability with capacity retention of 71.2%after 200 cycles at 1C and 54.8%after 400 cycles at 5C.Additionally,the full cell paired with hard carbon anode exhibits a remarkable long-term cycling stability,showing capacity retention of 64.1%after 250 cycles at 1C.These results demonstrate that Sc and Zn dual-substitution is an effective strategy to improve the Na^(+) diffusion dynamics and structural stability of NaMN.展开更多
Biapenem, a new parenteral carbapenem, has been widely used for treating bacterial infections. A simple, effective and accurate method based on solid-phase extraction （SPE） and HPLC was developed for the quantitativ...Biapenem, a new parenteral carbapenem, has been widely used for treating bacterial infections. A simple, effective and accurate method based on solid-phase extraction （SPE） and HPLC was developed for the quantitative determination of biapenem in human plasma. Stability and feasibility of the method was validated through a series of experiments. Using Vitamin B6 as an internal standard, analyte was separated on a Capcell Pak C18 column after SPE on Oasis hydrophilic-lipophilic balance （HLB） cartridge. The mobile phase was comprised of 0.05 mol/L NaH2PO4 （pH 5.7） and methanol （98：2, v/v） at a flow rate of 1.0 mL/min. Ultraviolet absorbance was measured at 300 nm. The calibration curve was linear in the concentration range of 0.04-50.00 μg/mL, and the lower limit of quantification was as low as 0.04 μg/mL. Recovery rates of biapenem at 0.10, 5.00, and 25.00 μg/mL were about 70%. The validated method has been successfully applied for quantifying biapenem in human samples and a pharmacokinetic study of 12 healthy volunteers who received three different doses （150, 300 and 600 mg） of biapenem by intravenous infusion. Our method has featured good accuracy and precision, and the processed sample was stable. Therefore, it can be propagated for clinical use.展开更多
A new HPLC-UV method was developed and validated for the quantitative determination of epidermal growth factor receptor inhibitor erlotinib in the plasma of tumor bearing BALB/c nude mice.Erlotinib and its internal st...A new HPLC-UV method was developed and validated for the quantitative determination of epidermal growth factor receptor inhibitor erlotinib in the plasma of tumor bearing BALB/c nude mice.Erlotinib and its internal standard l-（3-（（6,7-bis（2- methoxyethoxy）quinazolin-4-yl）amino）phenyl）ethanone were extracted from mice plasma samples using liquid-liquid extraction with a mixed solvent of methyl t-butyl ether and ethyl acetate（9：1,v/v）.Chromatographic separation was performed on a Luna C｜_（18）column（4.6 mm×250 mm,5μm）with acetonitrile：5 mM potassium phosphate buffer pH=5.2（41：59,v/v）as the mobile phase.UV detector was set at the wavelength of 345 nm,and the flow rate was 1.0 mL/min.The calibration curve was linear over the range of 20-10 000 ng/mL with acceptable intra-and inter-day precision and accuracy.The intra-day and inter-day precisions were within the range of 1.69%—5.66%,and the accuracies of intra-and inter-day assays were within the range of 105%—113%. The mean recoveries were 85.2%and 96.1%for erlotinib and IS,respectively.This method was successfully applied to a pharmacokinetic study in tumor bearing BALB/c nude mice following single oral administration at the dose of 12.5 mg/kg. The main pharmacokinetic parameters were as follows：C_（max）was 4.67μg/mL,T_（max）was 1.0 h,T_（1/2）was 2.78 h,and AUC_（0-24h）was 18.0μg/mL·h.展开更多
基金financial support from the National Natural Science Foundation of China(No.52377220)the Natural Science Foundation of Hunan Province,China(No.kq2208265)。
文摘Sc and Zn were introduced into O3-NaMn_(0.5)Ni_(0.5)O_(2)(NaMN)using the combination of solution combustion and solid-state method.The effect of Sc and Zn dual-substitution on Na^(+) diffusion dynamics and structural stability of NaMN was investigated.The physicochemical characterizations suggest that the introduction of Sc and Zn broaden Na^(+) diffusion channels and weaken the Na—O bonds,thereby facilitating the diffusion of sodium ions.Simulations indicate that the Sc and Zn dual-substitution decreases the diffusion barrier of Na-ions and improves the conductivity of the material.The dual-substituted NaMn_(0.5)Ni_(0.4)Sc_(0.04)Zn_(0.04)O_(2)(Na MNSZ44)cathode delivers impressive cycle stability with capacity retention of 71.2%after 200 cycles at 1C and 54.8%after 400 cycles at 5C.Additionally,the full cell paired with hard carbon anode exhibits a remarkable long-term cycling stability,showing capacity retention of 64.1%after 250 cycles at 1C.These results demonstrate that Sc and Zn dual-substitution is an effective strategy to improve the Na^(+) diffusion dynamics and structural stability of NaMN.
基金National Natural Science Foundation of China (Grant No.30973597)
文摘Biapenem, a new parenteral carbapenem, has been widely used for treating bacterial infections. A simple, effective and accurate method based on solid-phase extraction （SPE） and HPLC was developed for the quantitative determination of biapenem in human plasma. Stability and feasibility of the method was validated through a series of experiments. Using Vitamin B6 as an internal standard, analyte was separated on a Capcell Pak C18 column after SPE on Oasis hydrophilic-lipophilic balance （HLB） cartridge. The mobile phase was comprised of 0.05 mol/L NaH2PO4 （pH 5.7） and methanol （98：2, v/v） at a flow rate of 1.0 mL/min. Ultraviolet absorbance was measured at 300 nm. The calibration curve was linear in the concentration range of 0.04-50.00 μg/mL, and the lower limit of quantification was as low as 0.04 μg/mL. Recovery rates of biapenem at 0.10, 5.00, and 25.00 μg/mL were about 70%. The validated method has been successfully applied for quantifying biapenem in human samples and a pharmacokinetic study of 12 healthy volunteers who received three different doses （150, 300 and 600 mg） of biapenem by intravenous infusion. Our method has featured good accuracy and precision, and the processed sample was stable. Therefore, it can be propagated for clinical use.
基金National Integrity Innovational Technology Platform of New Drug and Development(Grant No.2009ZX09301- 010).
文摘A new HPLC-UV method was developed and validated for the quantitative determination of epidermal growth factor receptor inhibitor erlotinib in the plasma of tumor bearing BALB/c nude mice.Erlotinib and its internal standard l-（3-（（6,7-bis（2- methoxyethoxy）quinazolin-4-yl）amino）phenyl）ethanone were extracted from mice plasma samples using liquid-liquid extraction with a mixed solvent of methyl t-butyl ether and ethyl acetate（9：1,v/v）.Chromatographic separation was performed on a Luna C｜_（18）column（4.6 mm×250 mm,5μm）with acetonitrile：5 mM potassium phosphate buffer pH=5.2（41：59,v/v）as the mobile phase.UV detector was set at the wavelength of 345 nm,and the flow rate was 1.0 mL/min.The calibration curve was linear over the range of 20-10 000 ng/mL with acceptable intra-and inter-day precision and accuracy.The intra-day and inter-day precisions were within the range of 1.69%—5.66%,and the accuracies of intra-and inter-day assays were within the range of 105%—113%. The mean recoveries were 85.2%and 96.1%for erlotinib and IS,respectively.This method was successfully applied to a pharmacokinetic study in tumor bearing BALB/c nude mice following single oral administration at the dose of 12.5 mg/kg. The main pharmacokinetic parameters were as follows：C_（max）was 4.67μg/mL,T_（max）was 1.0 h,T_（1/2）was 2.78 h,and AUC_（0-24h）was 18.0μg/mL·h.
