Pharmacokinetic evaluation of paeoniflorin after oral administration of Paeoniae Radix extract powder to healthy Korean subjects using UPLC-MS/MS

Pharmacokinetics and Tissue Distribution Study of Modified Xiaochaihu Granules Against Gastric Ulcer Induced by Ethanol in Rats by UPLC-MS/MS

Gastric ulcer (GU) is one of the major gastrointestinal disorder diseases, with increasing incidence and prevalence globally. Modified Xiaochaihu granules (MXCHG) have been used effectively for treating chronic gastritis and GU clinically. To investigate the pharmacokinetics and tissue distribution of MXCHG, an ultraperformance liquid chromatography-electrospray ionization-tandem mass spectrometry (UPLC-ESI-MS/MS) method was established for the simultaneous determination of 8 bioactive ingredients (baicalin, wogonoside, baicalein, liquiritin, glycyrrhizic acid, berberine hydrochloride, saikosaponin a, and saikosaponin d) in rat plasma and various tissues using puerarin as an internal standard (IS). The biological samples were pretreated by protein precipitation with acetonitrile. The chromatographic separation was carried out on a C18 column with a gradient mobile phase consisting of acetonitrile and 0.1% formic acid in water. All analytes and IS were quantitated through ESI in the positive/negative ion multiple reaction monitoring mode. The mass transitions were as follows: m/z 445.0 → 268.5 for baicalin, m/z 458.7 → 282.8 for wogonoside, m/z 269.2 → 222.6 for baicalein, m/z 417.0 → 254.8 for liquiritin, m/z 822.1 → 350.8 for glycyrrhizic acid, m/ z 336.0 → 319.9 for berberine hydrochloride, m/z 780.3 → 618.5 for saikosaponin, and m/z 415.0 → 294.6 for the IS. The validated method was successfully applied to the pharmacokinetics and tissue distribution study of 8 compounds in rat plasma and tissues after the intragastric administration of MXCHG. The results demonstrated that 8 components were distributed widely and rapidly in various rat tissues after intravenous administration. Tissue deposition of the compounds in the rats was mainly in the small intestine and stomach. The present study can provide more useful information to guide the clinical use of MXCHG and the developed analytical method can also be applied for further clinical pharmacokinetic studies.

Simultaneous UPLC-MS/MS determination of four components of Socheongryong-tang tablet in human plasma: Application to pharmacokinetic study

The purpose of this study was to develop a method for simultaneous analysis of schizandrin, ephedrine, paeoniflorin, and cinnamic acid as constituents of Socheongryong-tang tablet in human plasma using UPLC-MS/MS. These four components were separated using water containing 0.01% formic acid and methanol as a mobile phase by gradient elution at a flow rate of 0.3 mL/min with a HALO-C₁₈ column (2.1 mm × 100 mm, 2.7 μm particle size). Quantitation was performed on a triple quadrupole mass spectrometer employing electrospray ionization technique operated in multiple reaction monitoring mode. Mass transitions were m/z 432.9 → 384.1 for schizandrin, 165.8 → 148.1 for ephedrine, 525.0 → 449.2 for paeoniflorin, 146.8 → 102.9 for cinnamic acid, and 340.0 → 324.0 for papaverine as internal standard. Liquid-liquid extraction and protein precipitation with ethyl acetate-methanol (1:2, v/v) were used to obtain these four components. Chromatograms showed high resolution, sensitivity, and selectivity without interference by plasma constituents. Calibration curves of schizandrin, ephedrine, paeoniflorin, and cinnamic acid in human plasma ranged from 0.02 to 8 ng/mL, 0.5 to 200 ng/mL, 0.2 to 80 ng/mL, and 1 to 400 ng/mL, respectively. Calibration curves of each analyte displayed excellent linearity, with correlation coefficients > 0.99. For all four components, both intra- and inter-day precisions (CV%) were <5.99%. The accuracy was 99.35-103.30% for schizandrin, 98.48-104.38% for ephedrine, 97.06-103.34% for paeoniflorin, and 99.97-104.36% for cinnamic acid. This analytical method developed in this study satisfied the criteria of international guidance. It could be successfully applied to pharmacokinetic studies of schizandrin, ephedrine, paeoniflorin, and cinnamic acid after oral administration of Socheongryong-tang tablet to humans.

Novel reverse electrodialysis-driven iontophoretic system for topical and transdermal delivery of poorly permeable therapeutic agents

Topical and transdermal drug delivery has great potential in non-invasive and non-oral administration of poorly bioavailable therapeutic agents. However, due to the barrier function of the stratum corneum, the drugs that can be clinically feasible candidates for topical and transdermal delivery have been limited to small-sized lipophilic molecules. Previously, we fabricated a novel iontophoretic system using reverse electrodialysis (RED) technology (RED system). However, no study has demonstrated its utility in topical and/or transdermal delivery of poorly permeable therapeutic agents. In this study, we report the topical delivery of fluorescein isothiocyanate (FITC)-hyaluronic acid (FITC-HA) and vitamin C and the transdermal delivery of lopinavir using our newly developed RED system in the in vitro hairless mouse skin and in vivo Sprague-Dawley rat models. The RED system significantly enhanced the efficiency of topical HA and vitamin C and transdermal lopinavir delivery. Moreover, the efficiency and safety of transdermal delivery using the RED system were comparable with those of a commercial ketoprofen patch formulation. Thus, the RED system can be a potential topical and transdermal delivery system for various poorly bioavailable pharmaceuticals including HA, vitamin C, and lopinavir.