ABSTRACT
OBJECTIVE：To develop a metho d for determining the plasma concentration of sulfasalazine （SSZ）metabolite sulfapyridine（SP）in rats ，and to investigate the effects of esomeprazole （ESOM）on the pharmacokinetic behavior of SSZ in rats. METHODS：Male SD rats were randomly divided into SSZ group and SSZ+ESOM group ，with 6 rats in each group. SSZ+ESOM group were given Esomeprazole enteric-coated tablets [ 90 mg/（kg·d）] intragastrically for 14 days. On the 15th day ，the rats in 2 groups were given Sulfasalazine enteric coated tablets （90 mg/kg）intragastrically，and blood sample was collected from the inner canthus at 0.5，1，1.5，2，3，4，6，8，10，12，24，36，48，72 h after administration. After protein precipitation with methanol ， using diazepam as internal standard ，Agilent XDR-C 18 column was adopted with methanol- 0.1％ formic acid solution （gradient elution）as mobile phase. The concentration of SSZ metabolite SP in plasma was determined by LC-MS/MS. The pharmacokinetic parameters were calculated by using DAS 3.0.1 software and compared between 2 groups. RESULTS ：The linear range of SP were 2-1 000 ng/mL. The methodology met the requirements of Chinese Pharmacopeia . There was no statistical significance in pharmacokinetic parameters of SP between 2 groups，such as AUC 0－t，tmax，t1/2z，cmax，MRT0－t（P＞0.05）. CONCLUSIONS ：The established method is simple ，rapid and sensitive ；it can be used for the concentration determination of SSZ metabolite SP in plasma. ESOM has no significant effect on the pharmacokinetic behavior of SSZ in rats.
ABSTRACT
Objective To develop a method of quantitative analysis of multi-components by single marker(QAMS) for determination of effective components of naphthopyrone glycosides and anthraquinone aglycone in Cassia tora L.Methods The separation was performed on a Sunfire C18 column (4.6 mm ×250 mm,5 μm), and column temperature 30 ℃.Aetonitrile-0.1% H3PO4 was used as the mobile phase with gradient elution.The detection wavelength was at 278 nm and 284 nm.Relative correction factor by determination of Between aurantio-obtusin and rubrofusarin-gentiobioside or chrysophanol or physcion.the method was evaluated for reproducibility, and the difference between calculated and measured values was compared. Results Rubrofusarin-gentiobioside, aurantio-obtusin, chrysophanol and physcion respectively 0.0503-1.5078, 0.3197-9.5899, 0.5070-15.2108, 0.4027-12.0814μg showed a good linear relationship, and the regression equation is Y =4.95X +2.01(R2 =0.9998),Y =1.03X +0.03(R2 =0.9999),Y=3.98X-0.12(R2 =0.9993),Y =4.81X +0.26(R2 =0.9996).The quantitative results of six batches of Cassia tora L by QAMS was basically consistent with that by external standard method.Conclusion The QAMS method was reliable and accurate, which might be used for the quality control of Cassia tora L.
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To investigate the pharmacokinetics of irinotecan hydrochloride (CPT-11) in rats and the tissue distribution of CPT-11 in mice after injection of irinotecan hydrochloride nanoparticles (CPT-11 NPs) via tail veins, separately, a LC-MS/MS method was established to determine the concentration of CPT-11 in whole blood of rats and in different tissues of mice. The pharmacokinetics and tissue distribution of CPT-11 were compared after the intravenous injection of CPT-11 NPs and CPT-11 solution. Compared with CPT-11 solution, the elimination half-life of CPT-11 was prolonged from 2.28 h to 3.95 h after the intravenous injection of CPT-11 NPs, and its AUC was 1.47 times than that of CPT-11 solution. After the injection of CPT-11 NPs in mice, the concentrations of CPT-11 loaded in CPT-11 NPs were significantly higher in the whole blood, colon and lungs than those in CPT-11 solution, but lower in the spleen, liver, kidney and heart, but the least in brain. CPT-11 NPs could improve CPT-11 's AUC, and help CPT-11 to reach long circulation activity.
ABSTRACT
OBJECTIVE:To establish a rapid and sensitive HPLC method for simultaneous determination of plasma concentrations of 6 antidepressants.METHODS:With diprozin as internal standard,the alkalized samples were extracted by liquid-liquid extraction and separated on a Phenomenex-C18 column using acetonitrile-0.05 mol?L-1 sodium dihydrogen phosphate(pH was adjusted to 2.5 by phosphoric acid) as mobile phase at a flow rate of 1.2 mL?min-1 by a gradient elution.The column temperature was set at 40℃.Venlafaxine was detected by fluorescence detection at an Ex wavelength of 276 nm and Em wavelength of 598 nm;doxepin,paroxetine,sertraline,fluoxetine and amitriptyline were detected at an UV detection wavelength of 200 nm.RESULTS:The linear ranges of venlafaxine,doxepin,paroxetine,sertraline,fluoxetine and amitriptyline were 5～1 000 ?g?L-1,40 ～200 ?g?L-1,20～800 ?g?L-1,40～1 000 ?g?L-1 and 10～400 ?g?L-1,respectively,with correlation coefficients ≥0.990 for all.Both the intra-day RSD and inter-day RSD were less than 15%;the extraction recovery rates were greater than 60% and methodological recovery were greater than 90% for all the samples.CONCLUSION:The method is simple,economical,rapid,accurate and sensitive,and it is applicable for the clinical monitoring of plasma drug concentrations as well as the analysis and pharmacokinetic study of toxic drugs.