Biomedical Chromatography最新文献

This study aimed to establish an UPLC-MS/MS method for determining memantine (MM) in rat plasma and to investigate its pharmacokinetic variations at different altitudes. MM was separated on a Hypersil Gold C18 column using a gradient elution method and detected by selected reaction monitoring (SRM). Sixteen fasted SD rats were randomized into low- and high-altitude groups (n = 8 each) and orally administered MM at 5 mg/kg. Serial blood samples were collected at 0-, 0.08-, 0.25-, 0.5-, 0.75-, 1-, 2-, 4-, 8-, 12-, 24-, 36-, and 48-h postdose for pharmacokinetic analysis. Compared with the low-altitude group, the high-altitude group exhibited a 72.15% increase in the area under the plasma concentration-time curve (AUC(0-∞)), a 39.97% reduction in apparent volume of distribution (Vz/F), the apparent clearance (CLz/F) decreased by 41.99%, the peak concentration (Cmax) increased by 131.52%, while the half-life (t_1/2) and time to peak concentration (Tmax) showed no significant changes. In conclusion, high-altitude hypoxia significantly affects MM metabolism in rats, potentially posing a risk of drug accumulation in plasma. The research findings provide a reference for the rational use of MM in high-altitude regions.

Chemical composition of propolis varies depending on geographical and environmental factors. This study presents a comprehensive characterization of propolis collected from four Northern Iraqi regions: Erbil, Mosul, Duhok, and Sulaymaniyah. The chemical content was examined through LC–MS/MS, ICP–MS, and GC–MS. Extracts were also evaluated for their antioxidant, enzyme inhibitory, and antimicrobial activities. LC–MS/MS profiling revealed notable regional and solvent-dependent variations in phenolic and flavonoid content, with ethanol extracts, particularly from Mosul and Sulaymaniyah, being richer in galangin, chrysin, and naringenin. GC–MS analysis identified several fatty acids and phenolic esters, with Duhok propolis containing high palmitic acid. ICP–MS analysis indicated variation in macroelements and trace elements, showing abundant calcium, magnesium, and iron. Ethanol extracts exhibited superior antioxidant activity in both DPPH radical scavenging and total antioxidant capacity, with Sulaymaniyah and Duhok extracts being the most active. Antimicrobial assays indicated inhibition against Salmonella typhimurium, Escherichia coli, Listeria monocytogenes, Bacillus subtilis, and Candida albicans, with Erbil and Sulaymaniyah extracts showing the strongest inhibition. Notably, Sulaymaniyah ethanol extract demonstrated the highest glutathione S-transferase (GST) inhibition activity (IC₅₀ = 5.52 μg/mL), correlating with its elevated flavonoid content. Overall, Northern Iraqi propolis displays chemical diversity and potent bioactivities, highlighting its promise for nutraceutical, pharmaceutical, and cosmetic applications.

Network pharmacology is instrumental in understanding how TCM works by targeting specific pathways. This study examines different mechanisms using three network pharmacology approaches, focusing on the TCM “Bai Mi Decoction” (BMD). The neuroprotective effects of BMD were evaluated in a middle cerebral artery occlusion–reperfusion (MCAO/R) rat model. The composition of BMD extract (BMDE) and its components in brain (BMDB) were analyzed using UHPLC-QTOF-MS/MS, alongside documented constituents from the database (BMDD). A network pharmacological analysis was conducted to explore the similarities and differences in BMD's neuroprotective mechanisms. BMD showed a strong neuroprotective effect in MCAO/R rats, as indicated by lower neurological deficit scores, smaller cerebellar infarct sizes, and improved histopathological changes. Analysis identified 45, 11, and 22 components in BMDE, BMDB, and BMDD, respectively, with 29, 26, and 23 potential therapeutic targets. However, most database-listed compounds were not found in actual samples. Functional enrichment and pathway network analysis showed that BMDE and BMDB shared the most targets. MAPK1 was the only common target across all groups, targeted by crocetin, the sole shared compound. BMD proved highly effective in MCAO/R rats, with compounds found in BMD extracts or in vivo better reflecting the actual pharmacological mechanisms than database-derived ones.

The primary active constituents in Corydalis Decumbentis Rhizoma (Xiatianwu, XTW) are isoquinoline alkaloids, which generally exhibit low oral bioavailability. This low bioavailability suggests that these compounds may be metabolized by gut microbiota prior to absorption. However, the characteristics of gut microbiota-mediated metabolism of XTW in vivo remain unclear. This study employed ultra-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry (UPLC-QTOF-MS/MS) to identify prototype compounds and metabolites of XTW in rat feces. The metabolic profiles of XTW between the control and pseudo-germ-free (GF) rats were systematically analyzed to delineate the gut microbiota-mediated metabolic profile of XTW in rat feces. In the control group, 92 compounds were identified, with 70 of them categorized as metabolites. In the pseudo-GF group, 80 compounds were identified, among which 44 compounds were categorized as metabolites. The significant reduction in metabolite diversity in the pseudo-GF group indicates that gut microbiota-mediated metabolism was suppressed. Moreover, the levels of certain prototype alkaloids and Phase I metabolites were significantly lower in the pseudo-GF group, while Phase II metabolites were compensatorily increased. The findings demonstrate that suppression of the gut microbiota alters the in vivo metabolism of XTW. These findings provide new evidence for understanding the role of gut microbiota in the metabolism of XTW.

In clinical treatment, compound kushen injection (CKI) is often used in combination with fluoxetine (FLX) to enhance the therapeutic effect on tumor-related depression in patients with tumors. To systematically investigate the pharmacokinetic interaction between CKI and FLX in plasma through UPLC–MS/MS analysis. Healthy male Sprague–Dawley rats were allocated to experimental or control groups; the experimental group received an injection of CKI (2 mg/kg) for 7 days, whereas the control group received an equivalent volume of saline. On Day 7, both groups received a single oral dose of FLX (10 mg/kg). Blood samples were subsequently collected from the tail vein at 15 time points over 72 h, after which the plasma concentrations of FLX were quantified using a validated UPLC–MS/MS method. The key pharmacokinetic parameters of FLX differed significantly (p < 0.05) between the two groups. Compared with those in the control group, the AUC_(0-∞), C_max, and T_1/2z of FLX in the experimental group increased by 457.06%, 248.25%, and 90.62%, respectively, while CL/F, V_z/F, and T_max decreased by 74.14%, 60.49%, and 41.11%, respectively. These findings demonstrate that CKI coadministration markedly alters FLX pharmacokinetics, potentially impacting treatment efficacy and safety.

Rubi Fructus (RF) is a traditional Chinese medicine that is both edible and medicinal. It is commonly used for daily health preservation by soaking in water and is also widely used in clinical treatment for kidney deficiency and frequent urination. Despite its extensive application, comprehensive pharmacokinetic studies on its multiple components are still relatively scarce. In order to systematically elucidate the in vivo dynamic processes of multiple components in RF, a simple and sensitive method was established and validated for the simultaneous determination of 14 compounds (ellagic acid, kaempferol-3-O-rutinoside, tiliroside, rutin, gallic acid, isoquercitrin, astragalin, kaempferol, p-coumaric acid, catechin, 3,4-dihydroxybenzaldehyde, protocatechuic acid, quercetin, and 4-hydroxybenzoic acid) in the plasma of rats by ultrahigh-performance liquid chromatography coupled with triple-quadrupole linear ion-trap tandem mass spectrometry (UHPLC-QTRAP-MS/MS). The method validation confirmed excellent linearity, acceptable precision and accuracy, as well as satisfactory extraction recovery and matrix effect for 14 compounds. The pharmacokinetic parameters of nine bioactive components in RF were successfully determined in rat plasma. A high C_max (1307.33 ng/mL) and a relatively long T_1/2 (10.62 h) were exhibited by ellagic acid. The findings provide a theoretical basis for elucidating its pharmacological mechanisms and clinical applications.

Vinblastine (VBL) and vincristine (VCR) are vinca alkaloids derived from Catharanthus roseus and are among the most widely used chemotherapeutic agents for treating hematological malignancies and solid tumors. Due to their narrow therapeutic index and complex structural nature, accurate, sensitive, and selective analytical methods are crucial for quantifying these drugs in pharmaceutical formulations, biological matrices, and environmental samples. This review provides a comprehensive overview of reported analytical techniques for VBL and VCR, drawing on major databases such as Scopus, Web of Science, ScienceDirect, PubMed, and Google Scholar, with a focus on the English-language literature. The discussed methods include chromatographic, spectroscopic, electroanalytical, and capillary electrophoretic techniques. High-performance liquid chromatography (HPLC), particularly when coupled with LC–MS/MS, offers exceptional sensitivity, with detection limits as low as 0.025 ng/mL in plasma. Conventional HPLC-UV methods, though less sensitive, remain widely applied in plant extract analysis. Electroanalytical approaches, such as voltammetry using nanomaterial-modified electrodes, offer eco-friendly and cost-effective alternatives with detection limits as low as 0.3 nM. Key analytical considerations include light sensitivity, pH and temperature control, and matrix interferences. Overall, recent methodological advancements enable reliable quantification of VBL and VCR, supporting safer clinical application, toxicity monitoring, and environmental surveillance.

This study employed an affinity chromatography approach to investigate the potential molecular mechanism of the Albiziae Cortex and Polygoni Multiflori Caulis herbal pair, which is commonly used for treating insomnia. Briefly, the haloalkane dehalogenase and its substrate were fused separately onto the serotonin 1A receptor and amino microspheres. Receptors were bound onto chromatographic stationary phases specifically through biological orthogonal interactions. Subsequently, catechin, methyl-O-digalloyl-hexose, 2,3,5,4′-tetrahydroxystilbene-2-O-β-D-glucoside (THSG), and julibroside J₃₅ were identified as active components in the herbal pair extract targeting the receptor. A mice model of insomnia was used to validate the anti-insomnia effects. The herbal-pair extract, catechin, and THSG significantly reduced sleep latency and increased sleep duration. Furthermore, on-column analysis and molecular docking revealed the binding characteristic. Adsorption isotherm analysis indicated a homogeneous binding process, which was further supported by injection amount-dependent analysis. The latter also provided binding constants of (5.70 ± 0.61) × 10⁵ M⁻¹ for catechin and (4.05 ± 0.20) × 10⁵ M⁻¹ for THSG. Molecular docking revealed critical binding residues (Asp116, Val117, Thr121, Lys191, Thr196, and Ser199), primarily via van der Waals forces and hydrogen bonds. Collectively, immobilizing the serotonin 1A receptor enables the screening of biologically active compounds from complex systems effectively and shows a degree of general applicability.

Banxia Xiexin Decoction (BXD), a classic traditional Chinese medicine formula traditionally used for gastrointestinal disorders, has demonstrated considerable therapeutic potential in ulcerative colitis (UC). Yet, its mechanism of action remains incompletely elucidated. In this study, we applied an integrated strategy incorporating UPLC-Q-TOF/MS-based plasma metabolomics and gut microbiome analysis to explore the anti-UC effects of BXD. In a DSS-induced murine model of UC, BXD treatment mitigated colonic inflammation, as evidenced by reduced levels of pro-inflammatory cytokines (IL-1β, IL-6, and TNF-α), repaired intestinal barrier integrity, and restored metabolic homeostasis via regulation of tryptophan and nitrogen metabolism. Notably, BXD promoted the production of microbially derived tryptophan metabolites, including indole-3-propionic acid (IPA) and indole-3-carboxaldehyde (IAld). IAld acts as a ligand for the aryl hydrocarbon receptor (AhR), facilitating the differentiation and function of regulatory T cells (Tregs) and thereby helping to suppress excessive inflammation. Gut microbiota analysis further indicated that BXD enriched beneficial genera such as Akkermansia and Bifidobacterium, while reducing the abundance of pro-inflammatory bacteria belonging to the Lachnospiraceae family. These results demonstrate the role of BXD in modulating the flora-metabolite-inflammation axis, providing a scientific rationale for its use in UC and highlighting its multi-target actions involving anti-inflammatory effects, metabolic reprogramming, and microbiota restoration.

Quercetin (QUE) is a natural flavonoid phyto-constituent found in fruits and vegetables with diverse medicinal properties. Green synthesis nanoparticles using plant extracts have gained attention for their eco-friendly and safe approach. The present work aimed to develop a facile, accurate, and reliable reverse-phase high-performance liquid chromatography (RP-HPLC) technique to determine QUE in nanoparticles. Chromatographic separation was done with a C18 column (4.6 × 250 mm, 5 μm) with a mobile phase of methanol and 0.1% orthophosphoric acid (OPA) (80:20, v/v) with a flow rate of 1.0 mL/min at 371 nm. The method developed for QUE proved to be highly linear in the range of 0.1–8.0 μg/mL (R²>0.999) with a retention time of 3.5 min. The limit of detection (LOD) and limit of quantification (LOQ) were 0.6 and 2.1 μg/mL, respectively. Validation parameters such as accuracy, precision, robustness, and specificity were in accordance with ICH guidelines. The novelty of the research work depends on attaining a maximum of QUE at a lower retention time compared to conventional methods.