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This study developed a simple, rapid, reproducible, and analytical method using liquid chromatography and electrospray ionization (ESI) with tandem mass spectrometry (LC-MS/MS) to simultaneously quantify pentoxifylline (PTX), its pharmacological active metabolites, lisofylline (PTX-M1) and 1-(3-carboxypropyl)-3,7-dimethylxanthine (PTX-M5), and donepezil (DNP) in rat plasma, using PTX-d6 and DNP-d7 as the internal standards. The LC-MS/MS procedure was performed at the ESI interface, operating in positive ionization and multiple reaction monitoring (MRM) modes; the monitoring of transitions comprised m/z 279.3 > 181.1 for PTX, m/z 281.1 > 263.1 > 160.90 for PTX-M1, m/z 267.1 > 249.0 > 220.9 for PTX-M5, m/z 380.3 > 90.9 for DNP, m/z 285.3 > 187.1 for PTX-d6 (IS1), and m/z 387.3 > 98.3 for DNP-d7 (IS2). After plasma protein precipitation (PP) with methanol, chromatographic separation was performed with an Imtakt Cadenza® CD-C18 (100 × 3 mm, 3 µm) column, using an isocratic mobile phase consisting of 0.1% formic acid in water and methanol (20:80, v/v) at a flow rate of 0.2 mL/min. The retention times of DNP, PTX-M5, PTX, and PTX-M1 were 2.24, 2.50, 2.68, and 2.72 min, respectively, with a total run time of 5 min. This method was validated over a linear concentration range of 5–8000, 10–5000, 20–15,000, and 2–500 ng mL−1 for PTX, PTX-M1, PTX-M5, and DNP, respectively, with a high correlation coefficient (r2 ≥ 0.99). The established method was fully validated in terms of selectivity, the lower limit of quantitation, precision, accuracy, recovery, matrix effect, stability, and dilution integrity according to the regulatory guidelines from the U.S. Food and Drug Administration and the Korea Ministry of Food and Drug Safety. The validated method was successfully applied to a pharmacokinetic study on the concurrent administration of DNP and PTX in rats. [ABSTRACT FROM AUTHOR]

Gongjindan (GJD) is a traditional Korean medicine consisting of four herbal medicines and two animal-derived medicines, and is taken as a tonic in Republic of Korea. In this study, the goal was to develop and validate a simultaneous analytical method to quantify eight compounds in commercially available GJD samples using high-performance liquid chromatography (HPLC), ultra-performance liquid chromatography with tandem mass spectrometry (UPLC–MS/MS), and gas chromatography with tandem mass spectrometry (GC–MS/MS) systems. In HPLC and UPLC–MS/MS, seven components (gallic acid, 5-(hydroxymethyl)furfural, morroniside, loganin, nodakenin, decursin, and decursinol angelate) were separated and quantified using a distilled water–acetonitrile mobile phase system on a Capcell Pak UG80 C18 column and an Acquity UPLC BEH C18 column, respectively. Muscone was quantified using GC–MS/MS. The developed assays were validated by evaluating the linearity, limit of detection, limit of quantitation, recovery, and precision. In the regression equations of all compounds, the coefficient of determination was ≥0.9917, showing good linearity. The recovery was 93.70–108.17%, and the relative standard deviation values in the precision test were all <1.50%. Using the developed analysis methods, GJD samples were determined to contain the eight target compounds in concentrations from non-detected to 10.75 mg/g. The analytical assays developed and validated in this study can be used to obtain data for the quality control of commercially available GJDs and for the further expansion of efficacy and clinical studies. [ABSTRACT FROM AUTHOR]

Zanthoxylum schinifolium Siebold et Zuccarini belongs to the Rutaceae family and has been widely used as a spice in East Asian countries such as Korea, China, and Japan. The present study focused on developing and validating a simultaneous analytical method for marker substances (bergapten and schinifoline) in Z. schinifolium seeds. This was achieved using high-performance liquid chromatography with a photo-diode array detector (HPLC-PDA) and ultra-performance liquid chromatography with tandem mass spectrometry (UPLC-MS/MS) systems. In the regression equation, all markers showed a coefficient of determination of ≥0.9990. Marker recovery was 96.90–105.16% (relative standard deviation (RSD) ≤ 2.23), and the intra- and interday precision was RSD < 3.00. Bergapten and schinifoline were detected in the seeds at 1.70–2.85 mg/g and 0.19–0.94 mg/g, respectively. This analytical method will improve quality control of Z. schinifolium seeds. Additionally, this assay will provide basic data and quality assurance for future biological activity experiments or clinical applications. [ABSTRACT FROM AUTHOR]

This study aimed to establish a simple and sensitive analytical method to simultaneously quantify donepezil (DPZ) and tadalafil (TAD) in rat plasma using lansoprazole (LPZ) as an internal standard (IS) by using liquid chromatography tandem mass spectrometry. The fragmentation pattern of DPZ, TAD, and IS was elucidated using multiple reaction monitoring in electrospray ionization positive ion mode for the quantification of precursor to production at m/z 380.1 → 91.2 for DPZ, m/z 390.2 → 268.1 for TAD, and m/z 370.3 → 252.0 for LPZ. The extracted DPZ and TAD from plasma using acetonitrile-induced protein precipitation was separated using Kinetex C18 (100 × 2.1 mm, 2.6 µm) column with a gradient mobile phase system consisting of 2 mM ammonium acetate and 0.1% formic acid in acetonitrile at a flow rate of 0.25 mL/min for 4 min. The selectivity, lower limit of quantification, linearity, precision, accuracy, stability, recovery, and matrix effect of this developed method was validated according to the guidelines of the U.S. Food and Drug Administration and the Ministry of Food and Drug Safety of Korea. The established method achieved acceptance criteria in all validation parameters, ensuring reliability, reproducibility, and accuracy, and was successfully implemented in a pharmacokinetic study on the co-administration of DPZ and TAD orally in rats. [ABSTRACT FROM AUTHOR]

Traditional East Asian medicine not only serves as a potential source of drug discovery, but also plays an important role in the healthcare systems of Korea, China, and Japan. Tandem mass spectrometry (MS/MS)-based untargeted metabolomics is a key methodology for high-throughput analysis of the complex chemical compositions of medicinal plants used in traditional East Asian medicine. This Data Descriptor documents the deposition to a public repository of a re-analyzable raw LC-MS/MS dataset of 337 medicinal plants listed in the Korean Pharmacopeia, in addition to a reference spectral library of 223 phytochemicals isolated from medicinal plants. Enhanced by recently developed repository-level data analysis pipelines, this information can serve as a reference dataset for MS/MS-based untargeted metabolomic analysis of plant specialized metabolites. Measurement(s) Metabolomics Technology Type(s) high-performance liquid chromatography-electrospray ionisation tandem mass spectrometry Sample Characteristic - Organism Embryophyta [ABSTRACT FROM AUTHOR]

Featured Application: Monitoring of residual pesticides in the environment is necessary to predict the impact of pesticide residue on ecosystems and human health. Pesticides have been used to control pests in agricultural fields and storage systems before circulating agricultural products to markets. A tandem mass spectrometry, equipped with gas chromatographic separation (GC–MS/MS) or ultra-performance liquid chromatographic separation (LC–MS/MS), was used to monitor residual pesticides in Korean rice paddy soils. Selective multiple reaction monitoring was employed during the analyses to achieve multiresidue pesticide analysis using GC–MS/MS and LC–MS/MS of 342 pesticides. In this study, QuEChERS extraction was employed with a dSPE clean-up to establish an effective pretreatment process. The limit of detection (LOD) and limit of quantification (LOQ) were set up for all pesticides, and method validation was performed for linearity and recovery at levels of 10 and 50 mg kg−1 in the untreated soil sample. All pesticides satisfied the acceptable recovery range of 70–120%, within less than 20% RSD values, except for ametoctradin and gibberellic acid. In the paddy soil analyses, tricyclazole was the most frequently detectable pesticide, followed by oxadiazon, endosulfan, and chlorantraniliprole. Continuous monitoring of residual pesticides in paddy soils should be conducted due to the translocation of some systemic pesticides from soils to crop plants, and the impact of residual pesticides on the environment. [ABSTRACT FROM AUTHOR]

Haepyoyijin-tang (HPYJT) is a traditional herbal prescription that is composed of 12 medicinal herbs. Although HPYJT is frequently used in patients with asthma in Korea, no quality assessment protocols have been developed. In the present study, qualitative and quantitative analyses were performed using high-performance liquid chromatography and liquid chromatography–tandem mass spectrometry on the eight main components (mulberroside A, amygalin, liquiritin apioside, liquiritin, narirutin, hesperidin, rosmarinic acid, and glycyrrhizinic acid) to establish a quality control protocol for HPYJT. The simultaneous analysis method developed was satisfactorily validated with respect to linearity, limit of detection, limit of quantification, recovery, and precision. This analytical method thus provides an efficient approach for the evaluation of HPYJT quality. [ABSTRACT FROM AUTHOR]

Sojadodamgangki-tang (SDGT) is a traditional Korean medicine consisting of 12 medicinal herbs that has been used in Korea for the treatment of asthma since ancient times. However, the quality control of herbal formulas that contain two or more herbal medicines remains challenging. In this study, 14 marker components were analyzed simultaneously by using high-performance liquid chromatography with photodiode array detection in addition to the use of liquid chromatography–tandem mass spectrometry for quality evaluation of SDGT. The simultaneous determination of the 14 marker components was validated in terms of linearity, recovery, and precision. The established methods can provide useful data for the quality control of SDGT and related herbal formulas. [ABSTRACT FROM AUTHOR]

In Europe, chemical castration has been adopted as a treatment for paraphilia since the 1930s. Among the various chemical castration agents, luteinizing hormone-releasing hormone (LHRH) agonists are now used widely because of their effectiveness and safety. In South Korea, a legislation of chemical castration to control the sexual impulses of sexual offenders was enforced in July 2011. Most of these subjects are treated with leuprorelin acetate, an LHRH agonist, for chemical castration. Despite this, there are few studies that address the long-term influence of LHRH agonists on testosterone (T) and epitestosterone (E) levels in chemical castration subjects. In order to analyze the urinary levels of T in chemical castration subjects, whose T levels are extremely low, we developed and validated an analytical method for the detection of both T and E in human urine using a liquid chromatography-tandem mass spectrometry (LC–MS/MS) system. The urine samples were hydrolyzed, extracted, and analyzed by LC–MS/MS with electrospray ionization in the positive-ion mode. The limits of detection were 0.02 ng/mL and the limits of quantitation were 0.05 ng/mL, which provided great sensitivity. The established method was applied to urine samples from chemical castration subjects and healthy male volunteers. The chemical castration subjects showed significantly lower urinary T levels than the control subjects. In addition, the urinary E levels were also lower in the chemical castration subjects; however, the T/E ratios were constant and did not show a notable decrease because of the simultaneous decrease in both urinary T and E. The urinary T levels and T/E ratio did not exceed the doping control criteria for exogenous T ingestion for any subject. This study shows the trend of urinary T and E levels in long-term treated chemical castration subjects by establishing a highly sensitive LC–MS/MS method, that provides useful information for monitoring chemical castration. [ABSTRACT FROM AUTHOR]

Ixeris dentata (Thunb. ex Thunb.) Nakai (Asteraceae), a well-known edible vegetable in Asia, contains various bioactive secondary metabolites, including sesquiterpene lactones. In this study, a high-performance liquid chromatography–tandem mass spectrometry (HPLC–MS/MS) method has been developed and validated for simultaneous determination of seven sesquiterpene lactone glucosides isolated from the roots of I. dentata. In addition, these compounds were evaluated in terms of their antiviral activities against coxsackievirus B3 (CVB3) and human enterovirus 71 (EV71). The developed method was validated in terms of linearity (R2 > 0.9996), precision (RSD < 2.24%), accuracy (96.30–102.77%), and stability (RSD < 1.94%) and successfully applied to the quantitation of the I. dentata root samples collected from six different regions of Korea. The content of sesquiterpene lactone glucosides varied significantly based on the region. For the antiviral activities, guaianolides with an ester group at C-8 (compounds 6 and 7) showed the most potent activities against CBV3, while germacranolide (compound 5) showed the most consistent antiviral activity against both CVB3 and EV71. The method was validated to be simple and reliable to simultaneously determine seven putative bioactive sesquiterpene lactone glucosides, the substantial chemotaxonomic markers, in I. dentata root samples. [ABSTRACT FROM AUTHOR]

Insamyangpye decoction (ISYPD) is an oriental herbal prescription used in Korea to treat lung-related diseases such as chronic obstructive pulmonary disease. ISYPD is a complex prescription consisting of 13 herbal medicines, and ISYPD sample was obtained by adding 50 L of distilled water to a mixture (5 kg) of 13 herbal medicines, extracting at 100 °C for 2 h using an electric extractor, and freeze-drying. In this study, an accurate and sensitive liquid chromatography tandem mass spectrometry (LC–MS/MS) method based on multiple reaction monitoring (MRM) was developed and verified for quality assessment of ISYPD using 10 marker components: mulberroside A (1), amygdalin (2), liquiritin apioside (3), naringin (4), poncirin (5), platycodin D (6), ginsenoside Rb1 (7), glycyrrhizin (8), saikosaponin A (9), and schizandrin (10). These marker compounds were separated using an Acquity UPLC BEH C18 column (2.1 mm × 50 mm, 1.7 μm) maintained at 30 °C with a mobile phase elution gradient of acetonitrile in distilled water, both containing 0.1% (v/v) trifluoroacetic acid. Marker components were quantified using the LC–MS/MS MRM method developed and validated, and found at 0.09–7.47 mg/g. [ABSTRACT FROM AUTHOR]

The Sogunjung decoction (SGJD) is a traditional herbal formula that has been used to treat constipation and improve the constitution of infirm children in Korea. In this study, simultaneous quantification of gallic acid (1), magnoflorine (2), albiflorin (3), paeoniflorin (4), liquiritin apioside (5), liquiritin (6), liquiritigenin (7), coumarin (8), cinnamaldehyde (9), benzoylpaeoniflorin (10), and glycyrrhizin (11) was conducted using fast and sensitive liquid chromatography–tandem mass spectrometry (LC–MS) multiple-reaction monitoring to develop a quality-control protocol for the SGJD. A Waters Acquity UPLC BEH C18 column (2.1 × 100 mm, 1.7 μm) was used for the chromatographic separation of the 11 marker compounds in the SGJD using two mobile phases (5 mM ammonium acetate in distilled water containing 0.1% (v/v) formic acid, and acetonitrile). The MS parameters for a simultaneous analysis were capillary voltage (3.0 kV), source temperature (150 °C), desolvation temperature (500 °C), desolvation gas flow (700 L/h), and cone gas flow (50 L/h). The developed LC–MS method was validated by the evaluation of linearity, limits of detection, limits of quantification, recovery and precision. By using the developed and validated assay, the 11 marker components in the SGJD were detected in amounts of 0.01–51.83 mg/g. [ABSTRACT FROM AUTHOR]