Simultaneous quantification of loureirin A and loureirin B in rat urine, feces, and bile by HPLC-MS/MS method and its application to excretion study

2011 ◽  
Vol 400 (4) ◽  
pp. 1181-1187 ◽  
Author(s):  
Yushi Zhang ◽  
Yongzhi Li ◽  
Bo Chen ◽  
Yulin Deng ◽  
Yujuan Li
2019 ◽  
Vol 15 (3) ◽  
pp. 266-272
Author(s):  
Jialin Sun ◽  
Wen Xu ◽  
Junke Song ◽  
Xiao Li ◽  
Qie Guo ◽  
...  

Background: Salvianolic acid A (SAA) is a polyphenolic acid extracted from Salvia miltiorrhiza Bunge. It showed protective effect against diabetic complications after oral administration with a low bioavailability of 1.42%. Attempts have been made to develop it into a new medication. Intracorporal process of SAA is indistinct and no report regarding the excretion is available. Our preliminary experiment revealed that previous reported methods were unsuitable for the excretion study due to the serious matrix effect. Methods: To better clarify its pharmacokinetics and avoid the interference of complex endogenous substances, a sensitive UPLC-MS/MS method with a better resolution was developed for the excretion study of SAA for the first time. The analytes were separated by reversed-phase chromatography with acetonitrile-water (containing 0.1% formic acid) gradient elution. The mass spectrometer was operated in the negative ESI mode and multiple reaction monitoring mode. Results: This method was linear over the concentration range of 2.5-100, 5-100 and 5-100 ng/mL in urine, feces and bile, respectively. The accuracy, precision, stability, recovery and matrix effect were satisfactory in all matrices examined. The validated method was successfully applied to an excretion study in rats. After oral administration of 20 mg/kg, the average accumulated excretion amount of SAA in urine, feces and bile were 99.80, 32046.30 and 161.03 ng, respectively. Conclusion: A quick but low elimination was observed. The date is useful for the clinical trial design of SAA.


2020 ◽  
Vol 21 ◽  
Author(s):  
Zedong Xiang ◽  
Shaoping Wang ◽  
Haoran Li ◽  
Pingping Dong ◽  
Fan Dong ◽  
...  

Background:: Catalpol, an iridoid glycoside, is one of the richest bioactive components present in Rehmannia glutinosa. More and more metabolites of drugs have exhibit various pharmacological effects, thus providing guidance for clinical application. However, few researches have paid attention on the metabolism of catalpol. Objective:: This study aimed to establish a rapid and effective method to identify catalpol metabolites and evaluate the biotransformation pathways of catalpol in rats. Methods:: In this study, catalpol metabolites in rat urine, plasma and faeces were analyzed by UHPLC-Q-Exactive MS for the characterization of metabolism of catalpol. Based on high-resolution extracted ion chromatograms (HREICs) and parallel reaction monitoring mode (PRM), metabolites of catalpol were identified by comparing the diagnostic product ions (DPIs), chromatographic retention times, neutral loss fragments (NLFs) and accurate mass measurement with those of catalpol reference standard. Results: A total of 29 catalpol metabolites were detected and identified in both negative and positive ion modes. Nine metabolic reactions including deglycosylation, hydroxylation, dihydroxylation, hydrogenation, dehydrogenation, oxidation of methylene to ketone, glucuronidation, glycine conjugation and cysteine conjugation were proposed. Conclusion:: A rapid and effective method based on UHPLC-Q-Exactive MS was developed to mine the metabolism information of catalpol. Results of metabolites and biotransformation pathways of catalpol suggested that when orally administrated, catalpol was firstly metabolized into catalpol aglycone, after which phase Ⅰ and phase Ⅱ reactions occurred. However, hydrophilic chromatography-mass spectrometry still needed to further find the polar metabolites of catalpol.


2020 ◽  
Vol 16 (3) ◽  
pp. 328-334
Author(s):  
Jie Ge ◽  
Jin-Wen Wang ◽  
Qi-Yan Guo ◽  
Ai-Dong Wen

Objective: A validated liquid chromatography-tandem mass spectrometry method (LCMS/ MS) was established to simultaneously determine the concentration of triflusal and its main metabolite 2-hydroxy-4-trifluoromethyl benzoic acid(HTB) in human urine. Methods: The separation was performed on a Dikma C18 column using isocratic elution with acetonitrile-4 mmol/L ammonium acetate aqueous solution containing 0.3 % formic acid water (78: 28, V/V). The method involved extraction with methanol using protein precipitation. The precursor-toproduct ion transitions with multiple reaction monitoring was m/z 247.1→161.1, 204.8→106.7and 136.9→93.0 for triflusal, HTB and salicylic acid(IS), respectively. The method showed good linear relationships over the ranges of 0.08 to 48 μg/mL and0.5 to 50 μg/mL. Results: It was the first time that a urinary excretion study of triflusal capsule as oral. The cumulative urinary recovery showed 8.5% and 2.7% for triflusal and HTB, respectively. Conclusion: This method was successfully used for evaluating the pharmacokinetic properties of triflusal and HTB in urine in Chinese healthy subjects.


2018 ◽  
Vol 15 (1) ◽  
pp. 17-23
Author(s):  
Vulli Srinandan ◽  
Krishnaveni Nagappan ◽  
Sonam Patel ◽  
Karthik Yamjala ◽  
Gowramma Byran ◽  
...  

Background: Pantoprazole (PTZ) and Levosulpiride (LS) were proven as effective agents for the treatment of Gastro-Esophageal Reflux Disease (GERD). It is a complex motor disorder that results in regurgitation of the gastric contents into the lower esophagus with consequent symptoms such as heart burn, retrosternal pain, dysphagia and belching. Methods: A rapid, sensitive, selective and specific liquid chromatography- electro spray ionization tandem mass spectrometry (LC-MS/MS) method was developed for the simultaneous quantification of Pantoprazole (PTZ) and Levosulpiride (LS) in spiked Human Plasma. The method utilized SPE as sample preparation technique and the analysis was carried out on a HPLC system utilizing electro spray ionization as interface and triple quadrupole mass analyzer for quantification in MRM possitive mode. Iloperidone was used as internal standard (IS). Chromatographic separation was performed on a Phenomenex C-18 Column (4.6 mm x 50 mm, 5µ) with an isocratic elution mode utilizing a mobile phase composition of Solution containing a mixture of 70 volumes of acetonitrile: 30 volumes of methanol and 10mM ammonium formate (pH 4.0) at the ratio of 80:20 % v/v. The flow rate was maintained at 0.3 mL/min. Results: PTZ, LS and IS were detected and quantified with proton adducts at m/z 383.37→200.00, m/z 341.42→112.15 and 426.48→261.00 respectively. The linearity and range was established by fortifying blank plasma samples in the concentration range of 3.5-2000 ng/mL for PTZ and 3.0-2400 ng/mL for LS. The correlation coefficient (r2) was found to be ≥ 0.993 for PTZ and (r2) ≥ 0.990 for LS. The lower limit of quantification for PTZ was 3.5 ng/mL and LS was 3.0 ng/mL. The intra and inter day precision and accuracy for PTZ and LS were within the limits fulfilling the international acceptance criteria. PTZ and LS were found to be stable throughout three freeze-thaw cycles, bench top and short term stability studies. Conclusion: The proposed validated LC-MS/MS method offers a sensitive quantification of PTZ and LS in spiked human plasma and can be utilized for the quantification of PTZ and LS in real-time samples.


1966 ◽  
Vol 211 (4) ◽  
pp. 975-980 ◽  
Author(s):  
WT Beraldo ◽  
RL Araujo ◽  
M Mares-Guia
Keyword(s):  

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