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Xue J.,National Institutes for Food and Drug Control | Zhang R.,National Institutes for Food and Drug Control | Tian Y.,National Institutes for Food and Drug Control | Hu C.-Q.,National Institutes for Food and Drug Control | And 2 more authors.
Chinese Journal of New Drugs | Year: 2014

Objective: To explore the salification property of a chemical crystalline compound with new structure named cefuroxime lysine.Methods: That cefuroxime lysine sample was in salt form was proved by infrared chemical imaging technology and 13C solid nuclear magnetic resonance technology associated with powder X-ray diffraction analysis and stability study.Results: It was shown that no free L-lysine was present in cefuroxime lysine crystalline compound and the site at which cefuroxime acid was conjugated with L-lysine was related to 4-carboxyl in cefuroxime acid, and the cefuroxime lysine sample was in specific crystal form with higher chemical stability.Conclusion: The results of this research suggested that cefuroxime is linked with lysine by a chemical bond to form a salt. Source

Cui Y.,Shenyang Pharmaceutical University | Cui Y.,Shandong Luoxin Pharmaceutical Co. | Ma N.,Liaoning Academy of Chinese Medicine | Li X.,Shenyang Pharmaceutical University | And 6 more authors.
Journal of Chromatography B: Analytical Technologies in the Biomedical and Life Sciences | Year: 2014

A new, sensitive and efficient ultra fast liquid chromatography-tandem mass spectrometry (UFLC-MS/MS) method has been developed and validated for simultaneous quantification of cefazedone and etimicin in beagle dog plasma. After addition of the internal standard (IS) metronidazole, plasma samples were treated by protein precipitation procedure, and then separated on a Venusil MP C18 column (100mm×2.1mm, 3.0μm) (Venusil, China) using gradient elution with the mobile phase consisting of 0.01% heptafluorobutyric acid (HFBA) in acetonitrile and 0.01% HFBA in water at a flow rate of 0.4mLmin-1. The detection of the analytes was performed on 4000Q UFLC-MS/MS system with turbo ion spray source in the positive ion and multiple reaction-monitoring (MRM) mode. The linear range was 1.0-200μgmL-1 for cefazedone and 0.5-100μgmL-1 for etimicin, with lower limits of quantification of 1.0 and 0.5μgmL-1, respectively. Intra-day and inter-day precisions were within 7.2% and 4.3%, respectively for both analytes, and the accuracy (relative error, RE, %) was less than 10.7% and 12.7%, respectively. The mean absolute extraction recoveries of analytes and IS from beagle dog plasma were all more than 73.22%. The validated method was successfully applied to the pharmacokinetic study of cefazedone and etimicin in beagle dog after intravenous administration of cefazedone injection combined with etimicin injection and the two single injections alone, respectively. The results indicated there were not obvious differences between the pharmacokinetic behaviors between the combined group and either of the single groups. © 2014 Elsevier B.V. Source

Cui Y.,Shenyang Pharmaceutical University | Cui Y.,Shandong Luoxin Pharmaceutical Co. | Jiang Z.,Shenyang Pharmaceutical University | Sun J.,Shenyang Pharmaceutical University | And 4 more authors.
Food Chemistry | Year: 2014

A simple, efficient and general HPLC method for the determination of enantiomeric purity of a series of (L)-amino acids was developed. In order to improve the detection sensitivity, pre-column derivatization was adopted and 7-chloro-4-nitrobenzoxadiazole (NBD-Cl) was selected as derivatization reagent. NBD-amino acid enantiomers were then enantioseparated on a Pirkle-type chiral stationary phase, Sumichiral OA-2500S (250 mm x 4.6 mm, 5 μm), using a mobile phase composed of acetonitrile-methanol (50:50, v/v) containing 5 mmol L -1 citric acid at the flow rate of 0.5 mL min-1. The detection wavelength was 470 nm. All the eleven pairs of tested amino acid enantiomers were well separated, and trace amounts of (D)-amino acids (0.5%) in the presence of a large excess of corresponding (L)-enantiomers could be quantified. The proposed method was validated in terms of selectivity, precision, linearity range, LOD, LOQ and accuracy, and then successfully applied to the determination of enantiomeric purity in bulk samples of (L)-amino acids. © 2014 Elsevier Ltd. All rights reserved. Source

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