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Patrinia scabiosaefolia Fisch. (PSF), a well-known traditional Chinese medicine, has been demonstrated to show therapeutic effects on inflammatory bowel disease. In this study, a rapid and sensitive method using ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UPLC/Q-TOF-MS) was developed for identification of the major constituents in PSF. The separation analysis was performed on Waters Acquity UPLC system, and the accurate mass of molecules and their fragment ions were determined by Q-TOF-MS. Thirty-one constituents, including triterpenoids, iridoids, flavonoids, and organic acids were detected and tentatively deduced on the basis of their element compositions, tandem mass spectrometry (MS/MS) data, and relevant literatures. Twelve constituents were discovered for the first time in PSF. The results demonstrated that hederagenin-type and oleanolic acid-type saponins were the main constituents of PSF. Our work provides a certain foundation for further quantitation of major chemical constituents and in vivo pharmacokinetic studies of PSF. Moreover, the analytical approach developed herein has proven to be generally applicable for profiling the chemical constituents in traditional Chinese medicines (TCMs) and other complicated mixtures.

Open access

A rapid method has been used for simultaneous identification of both hydrophilic and lipophilic compounds from Radix Salviae Miltiorrhizae (RSM, the root of Salvia miltiorrhiza BGE.) by ultra-performance liquid chromatography/quadrupole time-offlight mass spectrometry (UPLC/Q-TOF-MS). A total of 58 compounds extracted by methanol were detected and tentatively identified within 20 min, including hydrophilic phenolics, lipophilic diterpenoids, a verbascose, and several organic acids. These compounds were separated on an Acquity UPLC BEH C18 column and identified based on tandem mass spectrometry (MS/MS) fragmentation patterns under the positive and negative ion modes, respectively. Among them, micranthin B and 9-oxo-10E,12Zoctadecadienoic acid were reported in RSM for the first time. Their fragmentation patterns in electrospray ionization (ESI)—MS/MS spectra were first investigated by matching their accurate molecular masses. This contribution presented one of the first reports on the analysis of hydrophilic phenolics and lipophilic diterpenoids from Radix Salviae Miltiorrhizae using UPLC/Q-TOF-MS. The results demonstrated that UPLC/Q-TOF-MS method could be applied to rapidly and expediently describe and provide comprehensive chemical information for simultaneous analysis of two different polar components in RSM.

Open access

A fast, reliable, inexpensive, and practical method with a low determination limit and high recovery has been developed for the determination of the marijuana metabolite in routine analysis. THC-COOH in urine was validated using liquid chromatography—tandem mass spectrometry (LC—MS/MS). Before an easy single-step extraction with Toxi-Tubes, basic hydrolysis was performed at 60 °C for 30 min. LC—MS/MS analysis takes 2.5 min for each sample, and the retention time of the analyte is 1.75 min. Specificity, linearity, limit of detection (LOD), limit of quantification (LOQ), accuracy, repeatability, and intermediate precision (inter-day) system suitability parameters were determined in the validation study. The recovery of the extraction method was 88.67 (±5.91). LOD and LOQ values were 1.41 and 5.00 ng mL−1, respectively. The method showed linear response between the values 5.00 and 500.00 ng mL−1. The repeatability was 9.64% (relative standard deviation, RSD%), and the intermediate precisions (RSDR%) were 10.73%, 13.74%, and 8.11% at 10.00, 100.00, and 200.00 ng mL−1 concentration levels, respectively. No statistically significant difference was found in ANOVA analysis, between three consecutive days in intermediate precision study, for 90% confidence level. HorRat values were between 0.34 and 0.61. The method was applied to CEDIA positive samples, obtained from the Trabzon Group Presidency of Turkish Council of Forensic Medicine, successfully.

Open access

In the present study, the degradation behavior of Fenofibrate under different International Conference on Harmonization (ICH) suggested conditions was studied. Characterization of degradation products by liquid chromatography–tandem mass spectrometry (LC–MS/MS) studies in solution form was done, and the possible mechanism for the formation of degradants is discussed. Fenofibrate was subjected to different hydrolytic stress conditions and thermal stress condition (in solid form). Successful separation of drug from degradants was achieved on a C18 column using water–acetonitrile (25:75 v/v) as the mobile phase. Other high-performance liquid chromatography (HPLC) parameters were: flow rate, 1 mL min−1; detection wavelength, 286 nm; column temperature, 25 °C; and injection volume, 20 μL. The method was validated for linearity, precision, accuracy, robustness, and specificity and was stability-indicating one, based on the specificity studies. The drug degraded under acidic, basic, and oxidative hydrolytic stress while it was relatively stable towards neutral hydrolysis and thermal stress. The stressed samples were subjected to LC–MS/MS analysis. On the basis of spectral data, the structures of four degradation products and one interaction product were suggested. Degradation products were characterized to be isopropyl acetate, 2-[4-(4-chlorobenzoyl)phenoxy]-2-methyl propanoic acid, 4-hydroxy benzoic acid, and benzoic acid. The structure of one interaction product was proposed as methyl 2-[4-(4-chlorobenzoyl)phenoxy]-2-methylpropanoate.

Open access

Abstract

Palmatine is a compound with good water solubility extracted from Coptis chinensis, Fibraurea recisa Pierre, Cortex Phellodendri Chinensis. Palmatine has good antibacterial activity and mainly used for the treatment of bacterial dysentery, gynecological inflammation, surgical infection, and conjunctivitis. It has anti-diabetic, anti-oxidant, and cognitive-enhancing activities. In this study, we used UPLC-MS/MS to determinate palmatine in rat plasma, and investigated its pharmacokinetics. Coptisine was utilized as an internal standard (IS), and acetonitrile precipitation method was used to process the plasma samples. Chromatographic separation was achieved using a UPLC BEH C18 column using mobile phase of acetonitrile- 0.1% formic acid with gradient elution. Electrospray ionization (ESI) tandem mass spectrometry in multiple reaction monitoring (MRM) mode with positive ionization was applied. The results indicated that within the range of 1–500 ng/mL, linearity of palmatine in rat plasma was acceptable (r > 0.995), and the lower limit of quantification (LLOQ) was 1 ng/mL. Intra-day and inter-day precision RSD of palmatine in rat plasma were less than 14%. Accuracy range was between 93.7 and 107.1%, and matrix effect was between 101.6 and 109.4%. The method was successfully applied in the pharmacokinetics of palmatine in rats after oral and intravenous administration. The absolute bioavailability of the palmatine was 15.5% in rats.

Open access

Eupatilin, mainly derived from Artemisia asiatica (Asteraceae), is an O-methylated flavone with various bioactivities. In the present study, a validated ultra-performance liquid chromatography–tandem mass spectrometry (UPLC–MS/MS) method was established for the quantification of eupatilin in rat plasma with the internal standard (IS) of tussilagone and the protein precipitation of plasma samples was performed using acetonitrile–methanol (9:1, v/v). The eupatilin and IS were eluted separately on a UPLC BEH C18 column (2.1 mm × 100 mm, 1.7 μm) with the gradient mobile phase consisted of 0.1% formic acid and acetonitrile. The protonated analytes were quantified by multiple reactions monitoring (MRM) mode with an electrospray ionization (ESI) source operated in positive ion mode. The calibration plots were found to be linear over the range from 2 to 1000 ng/mL for eupatilin in rat plasma. Both of the intra-day and inter-day precision variations (RSDs) were ≤13%. The recoveries of eupatilin in rat plasma were between 83.7% and 94.6%, and the accuracy of the method ranged from 95.8% to 107.6%. In addition, the validated method was applied to pharmacokinetic study of eupatilin after an intravenous dose of 2 mg/kg to rats.

Open access
Acta Chromatographica
Authors: Biljana K. Tubić, Bojan D. Marković, Sandra S. Vladimirov, Slavica M. Ristić, Branka M. Ivković, Miroslav M. Savić, Jelena M. Poljarević, and Tibor J. Sabo

A series of new (S,S)-ethylenediamine-N,N′-di-2-(3-cyclohexyl)propanoate esters has shown cytotoxic activity towards human leukemic cell lines. The aim of this study was to develop and validate a bioanalytical method for quantification of (S,S)-O,O-diethyl-ethylenediamine-N,N′-di-2-(3-cyclohexyl)propanoate dihydrochlorides (DE-EDCP) and its metabolite, substituted propanoic acid (EDCP), in mouse serum by ultra high-performance liquid chromatography—tandem mass spectrometry (UHPLC—MS/MS). Structural analog, derivative of 1,3-propanediamine, was used as an internal standard (IS). Sample preparation employed protein precipitation by acetonitrile and subsequent centrifugation. Optimal UHPLC separation conditions were set to achieve simultaneous determination of both compounds in a short run time of 6 min. Additionally, the selected reaction monitoring (SRM) mode developed in this method allowed a highly sensitive, accurate, and precise identification of compounds of interest. The lower limit of quantitation (LOQ) was 1.3 ng mL−1 for DE-EDCP and 0.3 μg mL−1 for EDCP. The calibration curves were linear over the concentration range of 1.3–26.7 ng mL−1 and 0.3–6.7 μg mL−1 for DE-EDCP and EDCP, respectively. Precision (%CV) and accuracy (%RE) for DE-EDCP and EDCP ranged from 3.5% to 16.0% and from 1.8% to 14.4%, respectively.

The validation process was performed in accordance with the regulatory guidance/guideline, and all of the obtained results met the established acceptance criteria. The newly developed and validated UHPLC—MS/MS method is rapid, sensitive, and selective, and it can be successfully applied to drug monitoring in nonclinical studies.

Open access

The effect of free-range versus cage management system on corticosterone transfer into the eggs was studied in laying hens. Hungarian Yellow laying hens (age: 21 weeks, body weight: 2.0 ± 0.5 kg) were divided into two groups in the spring: Group I, free-range keeping (n = 15 layers, density: ≯ 0.5 bird/m2) in outdoor runs, with continuous access to a commercial layer feed; Group II, hens kept in battery cages (n = 17 layers, density: 2 birds/m2, natural light, continuous access to feed and water). Eggs were collected after a one-week adaptation period on days 2, 7 and 16. Corticosterone (CST) was extracted from homogenised egg samples using an ASE-200 Accelerated Solvent Extractor and then assayed by liquid chromatography linked with tandem mass spectrometry (LC-MS/MS) [Thermo Quest Surveyor high-performance liquid chromatography (HPLC) interfaced via Atmospheric Pressure Chemical Ionisation (APCI) ion source to Finnigan/Thermo Quest LCQ Deca MS/MS] using dexamethasone as internal standard with positive APCI ionisation. CST concentrations of whole eggs laid by free-range hens on days 2, 7 and 16 were 0.370 ± 0.218, 0.259 ± 0.066 and 0.915 ± 0.745 ng·g-1, respectively, while those of eggs laid by caged hens were 0.206 ± 0.157, 0.223 ± 0.165 and 0.184 ± 0.110 ng·g-1 at the above sampling times. It is concluded that in free-range laying hens the sharp changes of environmental weather conditions significantly increased the corticosterone content of eggs, while the environmentally controlled and closed battery cage management technology resulted in relatively uniform corticosterone concentrations in the whole eggs.

Restricted access

A simple and sensitive liquid chromatography—tandem mass spectrometry method was developed for the quantification of atorvastatin, ortho-hydroxyatorvastatin, para-hydroxyatorvastatin, and atorvastatin lactone in rat plasma. Solid-phase extraction was used for preparation of samples. Rosuvastatin was chosen as an internal standard. Chromatographic separation was achieved on ZORBAX Eclipse C18 Analytical, 4.6 × 100 mm (3.5 μm) column with a gradient mobile phase composed of acetonitrile and 0.1% acetic acid, at a flow rate of 400 μL min−1. The column was kept at constant temperature (25 °C), and autosampler tray temperature was set at 4 °C. The following selected reaction monitoring (SRM) transitions were selected: (m/z, Q1 → Q3, collision energy) atorvastatin (559.47 → 440.03, 22 eV), atorvastatin lactone (541.36 → 448.02, 19 eV), ortho-ohydroxyatorvastatin (575.20 → 440.18, 20 eV), para-hydroxyatorvastatin (575.54 → 440.18, 20 eV), and rosuvastatin (482.25 with selected combination of two fragments 257.77, 31 eV, and 299.81, 35 eV) in positive ion mode. The method was validated over a concentration range of 0.5–20 ng mL−1 for ortho-hydroxyatorvastatin and para-hydroxyatorvastatin and 0.1–20 ng mL−1 for atorvastatin and atorvastatin lactone with excellent linearity (r 2 ≥ 0.99). This method demonstrated acceptable precision and accuracy at four quality control concentration levels. The detection limits were 0.1 and 0.13 ng mL−1 for orth-ohydroxyatorvastatin and para-hydroxyatorvastatin, respectively, and 0.05 ng mL−1 for atorvastatin and atorvastatin lactone. All analytes were found to be stable at examined conditions. Validated method was applied for determination of atorvastatin and its metabolites in plasma of experimental animals.

Open access
Acta Chromatographica
Authors: Weijian Ye, Wei Sun, Ruijie Chen, Zhe Wang, Xiao Cui, Hui Zhang, Shuyi Qian, Qi Zheng, Yangfeng Zhou, Jiafeng Wan, Jiali Xu, Xianqin Wang, and Yunfang Zhou

Galangin (GAL), the major bioactive flavonol extracted from Alpinia officinarum Hance (Zingiberaceae), has attracted much attention due to its multiple biological activities. To develop a fast, reliable, and sensitive ultrahigh-performance liquid chromatography–tandem mass spectrometry (UHPLC–MS/MS) method for the quantification of GAL in rat plasma and mouse tissues. UHPLC–MS/MS using electrospray ionization operating in negative-ion mode was used to determinate GAL in 18 rats receiving three doses of GAL (2 and 9 mg/kg by intravenous injection, 5 mg/kg by oral administration), with six rats for each dose. Blood samples were collected at 0.0333, 0.25, 0.5, 1, 2, 4, 6 and 8 h. A total of 25 mice received 18 mg/kg GAL by intraperitoneal injection. Liver, heart, lung, spleen, brain, and kidney tissue samples were collected at 0.25, 0.5, 2, 4, and 6 h. The precision of the method was better than 12.1%, while the accuracy ranged from −4.8% to 8.1%. The results of pharmacokinetics demonstrated rapid GAL absorption (t max of 0.25 h), fast elimination (t 1/2 <1.1 h) after three different dosages, and an absolute bioavailability of ~7.6%. Tissue distribution analysis revealed abundant GAL in liver, kidney, spleen, and lung and smaller amounts in brain. The developed method proved fast (3 min), efficient, and reliable, with high selectivity for the quantitative analysis of GAL in biological samples. This is the first study to identify the target tissues of GAL, and the results may help to elucidate the mechanisms underlying its therapeutic effects in vivo.

Open access