LC-MS/MS analysis and evaluation of the anti-inflammatory activity of components from BushenHuoxue decoction

Bushen Huoxue decotion-containing serum prevents chondrocyte pyroptosis in a m6A-dependent manner in facet joint osteoarthritis

BACKGROUND

Facet joint osteoarthritis (FJOA) is a common lumbar osteoarthritis characterized by degeneration of small joint cartilage. Bushen Huoxue decotion (BSHXD) has good therapeutic effects on OA. Our work aimed to further probe the pharmacological effects of BSHXD-containing serum (BSHXD-CS) on FJOA and define underlying the mechanisms invovled.

METHODS

To establish a FJOA cell model, primary rat chondrocytes were treated with LPS. The mRNA and protein expressions were assessed using qRT-PCR and western blot, respectively. The secretion levels of pro-inflammatory cytokines were measured by ELISA. Cell viability was determined by CCK8 assay. The global m6A level was detected by the kit, and NLRP3 mRNA m6A level was determined by Me-RIP assay. The molecular interactions were analyzed by RIP and RNA pull-down assays.

RESULTS

BSHXD-CS treatment relieved LPS-induced cell injury, inflammation, NLRP3 inflammasome and pyroptosis in chondrocytes (all p < 0.05). LPS-induced NLRP3 upregulation in chondrocytes was related to its high m6A modification level (p < 0.05). It was also observed that BSHXD-CS reduced LPS-induced m6A modification in chondrocytes via repressing STAT3 (all p < 0.05), suggesting BSHXD-CS could repress NLRP3 expression via m6A-dependent manner. Moreover, DAA, a m6A specific inhibitor, was proved to strengthen the protectively roles of BSHXD-CS on LPS-challenged pytoptosis (all p < 0.05).

CONCLUSION

BSHXD-CS inhibited NLRP3 inflammasome activation and pyroptosis in chondrocytes to repress OA progression by reducing RNA m6A modification.

Revealing the potential bioactive components and mechanism of Qianhua Gout Capsules in the treatment of gouty arthritis through network pharmacology, molecular docking and pharmacodynamic study strategies

Recent clinical studies have confirmed the effectiveness of Qianhua Gout Capsules (QGC) in the treatment of gouty arthritis (GA). However, the specific regulatory targets and mechanisms of action of QGC are still unclear. To address this gap, we utilized network pharmacology, molecular docking, and pharmacodynamic approaches to investigate the bioactive components and associated mechanisms of QGC in the treatment of GA. By employing UPLC-Q Exactive-MS, we identified the compounds present in QGC, with active ingredients defined as those with oral bioavailability ≥30 % and drug similarity ≥0.18. Subsequently, the targets of these active compounds were determined using the TCMSP database, while GA-related targets were identified from DisGeNET, GeneCards, TTD, OMIM, and DrugBank databases. Further analysis including PPI analysis, GO analysis, and KEGG pathway enrichment was conducted on the targets. Validation of the predicted results was performed using a GA rat model, evaluating pathological changes, inflammatory markers, and pathway protein expression. Our results revealed a total of 130 components, 44 active components, 16 potential shared targets, GO-enriched terms, and 47 signaling pathways related to disease targets. Key active ingredients included quercetin, kaempferol, β-sitosterol, luteolin, and wogonin. The PPI analysis highlighted five targets (PPARG, IL-6, MMP-9, IL-1β, CXCL-8) with the highest connectivity, predominantly enriched in the IL-17 signaling pathway. Molecular docking experiments demonstrated strong binding of CXCL8, IL-1β, IL-6, MMP9, and PPARG targets with the top five active compounds. Furthermore, animal experiments confirmed the efficacy of QGC in treating GA in rats, showing reductions in TNF-α, IL-6, and MDA levels, and increases in SOD levels in serum. In synovial tissues, QGC treatment upregulated CXCL8 and PPARG expression, while downregulating IL-1β, MMP9, and IL-6 expression. In conclusion, this study applied a network pharmacology approach to uncover the composition of QGC, predict its pharmacological interactions, and demonstrate its in vivo efficacy, providing insights into the anti-GA mechanisms of QGC. These findings pave the way for future investigations into the therapeutic mechanisms underlying QGC's effectiveness in the treatment of GA.

Comprehensive multicomponent characterization and quality assessment of Xiaoyao Wan by UPLC-Q-Orbitrap-MS, HS-SPME-GC-MS and HS-GC-IMS

Xiaoyao Wan (XYW) is a prescription medicine of traditional Chinese medicine (TCM) with the effects of "soothing the liver and relieving depression," and "strengthening spleen and nourishing blood". XYW has been widely concerned in the treatment of depression and has become one of the commonly used classic formulas in clinical practice. However, the pharmacodynamic substance basis and the quality control studies of XYW are hitherto quite limited. Here, we aim to fully utilize an advanced ultra - performance liquid chromatography-quadrupole - Orbitrap mass spectrometry (UPLC-Q-Orbitrap-MS), headspace-solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) and headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS) technique to deep characterization of the pharmacological substance basis and quantitatively evaluate the quality of XYW. Firstly, 299 compounds were identified or tentatively characterized, including 198 non-volatile organic compounds (n-VOCs) and 101 volatile organic compounds (VOCs). Secondly, principal component analysis (PCA) and hierarchical cluster analysis (HCA) was used to analyze quality differences in XYW at different manufacturers. Thirdly, a parallel reaction monitoring (PRM) method was established and validated to quantify the fourteen major effective substances in different manufacturers of XYW, which were chosen as the benchmarked substances to evaluate the quality of XYW. In conclusion, this study shows that the strategy provides a useful method for quality control of TCM and offers a practical workflow for exploring the quality consistency of TCM.

Analytical Methods for the Determination of Quercetin and Quercetin Glycosides in Pharmaceuticals and Biological Samples

Flavonoids are plant-derived compounds that have several health benefits, including antioxidative, anti-inflammatory, anti-mutagenic, and anti-carcinogenic effects. Quercetin is a flavonoid that is widely present in various fruits, vegetables, and drinks. Accurate determination of quercetin in different samples is of great importance for its potential health benefits. This review, is an overview of sample preparation and determination methods for quercetin in diverse matrices. Previous research on sample preparation and determination methods for quercetin are summarized, highlighting the advantages and disadvantages of each method and providing insights into recent developments in quercetin sample treatment. Various analytical techniques are discussed including spectroscopic, chromatographic, electrophoretic, and electrochemical methods for the determination of quercetin and its derivatives in different samples. UV-Vis (Ultraviolet-visible) spectrophotometry is simple and inexpensive but lacks selectivity. Chromatographic techniques (HPLC, GC) offer selectivity and sensitivity, while electrophoretic and electrochemical methods provide high resolution and low detection limits, respectively. The aim of this review is to comprehensively explore the determination methods for quercetin and quercetin glycosides in diverse matrices, with emphasis on pharmaceutical and biological samples. The review also provides a theoretical basis for method development and application for the analysis of quercetin and quercetin glycosides in real samples.

Metabolites Profiling and In Vitro Biological Characterization of Different Fractions of Cliona sp. Marine Sponge from the Red Sea Egypt

Red Sea marine sponges are an important source of biologically active natural products. Therefore, the present study aimed to investigate, for the first time, the components of n-hexane, dichloromethane, and ethyl acetate fractions of Cliona sp. marine sponge collected from the Red Sea, Egypt using UPLC-ESI-MS/MS (Ultra-performance liquid chromatography electrospray ionization tandem mass spectrometry) analysis. The analysis revealed the tentative identification of 23, 16, and 24 compounds from the n-hexane, dichloromethane, and ethyl acetate fractions of Cliona sp., respectively. In addition, the examination of these fractions resulted in the isolation and identification of three sterols and one amino acid. The identification of the isolated compounds was confirmed by 1D and 2D NMR (Nuclear Magnetic Resonance), and MS (Mass spectrometry), and IR (Infrared) spectroscopy. The in vitro cytotoxic, antioxidant, and antimicrobial activities of the total ethanolic extract and its sub-fractions were also evaluated. Interestingly, the ethyl acetate fraction showed potent cytotoxic activity against colon (HCT-116) and human larynx carcinoma (HEP-2) cell lines with IC₅₀ (Half-maximal Inhibitory Concentration) 6.11 ± 0.2 and 12.6 ± 0.9 µg/mL, respectively. However, the dichloromethane fraction showed strong antioxidant activity, with IC₅₀ 75.53 ± 3.41 µg/mL. Notably, the total ethanolic extract showed the strongest antibacterial activity against Staphylococcus aureus and Escherichia coli, with MIC (Minimum Inhibitory Concentration) 62.5 ± 0.82 and 125 ± 0.62 µg/mL, respectively, compared to other fractions. In conclusion, this is the first report on the secondary metabolites content and biological activities of Cliona sp. from the Red Sea, Egypt. It also highlights the need for further research on the most active fractions against various cancer cell lines and resistant bacterial and fungal strains. Cliona sp. extract and its fractions could be a potential source of novel and safe natural drugs with a wide range of medicinal and pharmaceutical applications.

Rapid and comprehensive identification of chemical constituents in Mai-Luo-Shu-Tong pill by UHPLC-Q-Orbitrap HRMS combined with a data mining strategy

Mai-Luo-Shu-Tong pill is an effective traditional Chinese medicine formula for the treatment of superficial thrombophlebitis, but it was insufficiently chemically scrutinized. In this study, the mass spectral data of Mai-Luo-Shu-Tong pill were acquired by ultra-high performance liquid chromatography coupled with Q Exactive hybrid Quadrupole-Orbitrap high resolution mass spectrometry. Then, a data mining strategy combining multiple data processing methods was used to identify chemical constituents in Mai-Luo-Shu-Tong pill by constructing a database of precursor ions and summarizing the mass spectral fragmentation behaviors. As a result, a total of 211 compounds including 70 flavonoids, 56 terpenoids, 37 phenolic acids and 48 others were identified in positive and negative ion modes. Among them, 66 compounds have passed comparison verification with reference standards, 145 compounds were identified based on the data mining strategy combining the characteristic cleavage behaviour of homologous compounds and fragment ions and 4 compounds were potentially new compounds. This study provides a database for quality evaluation and further study of Mai-Luo-Shu-Tong pill in vivo. Moreover, it provides a reference for the characterization of the chemical constituents of other traditional Chinese medicine formulae.

Epoxymicheliolide directly targets histone H2B to inhibit neuroinflammation via recruiting E3 ligase RNF20

Monoubiquitination plays a critical role as one of the largest histone post-translational modifications (PTMs). Recent study has revealed that histone H2B monoubiquitination (H2Bub1) at a unique lysine 120 (K120) is widely involved in the development of inflammation progression. However, small-molecules directly targeting H2B to exert anti-inflammation effects via editing monoubiquitination have not been hitherto reported. In this study, we first discover a natural small-molecule epoxymicheliolide (ECL), which directly binds to H2B to inhibit microglia-mediated neuroinflammation in vitro and in vivo. Mechanism study suggests that ECL covalently modifies a previously undisclosed lysine 46 (K46) in H2B, and recruits E3 ubiquitin ligase RNF20 to promote H2Bub1 at K120. ChIP-seq and transcriptomics further reveal that ECL-mediated H2Bub1 markedly disrupts the AP-1 recruitment to proinflammatory gene promoters for microglia inactivation. Collectively, our findings suggests that K46 of H2B serves as a promising pharmacological target to develop small-molecule drugs against microglia-mediated neuroinflammation, and ECL represents a valuable lead compound for neuroinflammation via regulating histone monoubiquitination.

A strategy for intelligent chemical profiling-guided precise quantitation of multi-components in traditional Chinese medicine formulae-QiangHuoShengShi decoction

Due to the tremendous clinical value, more and more Traditional Chinese Medicines (TCMs) and their formulae are attracted by world's attention. QiangHuoShengShi (QHSS) decoction is one of classic TCM formulae, which is clinically used for treating various rheumatic diseases. However, the phytochemical constituents of QHSS have rarely been reported. A simple, intelligent, and comprehensive strategy was developed to characterize the phytochemical-fingerprint and quantify the chemical-markers for precise quality evaluation of QHSS. Firstly, a new deep-learning assisted mass defect filter (MDF) method was built for rapid and accurate classification of mass spectrum (MS) ions acquired by ultra-high performance liquid chromatography quadrupole time of flight tandem mass spectrometry (UHPLC-Q-TOF/MS). Subsequently, herb species-specific chemical-category and characteristic identification were used for further characterization of multi-components. As the result, seven major types of compounds in QHSS were intelligently differentiated and 183 phytochemical compounds were tentatively identified. Finally, a sensitive scheduled multiple reaction monitoring (sMRM) detection method was applied to precisely quantify 37 target analytes in QHSS decoction. This integrated strategy would provide an alternative method for chemical-material basis study of more herbal medicine or natural products.

Reduning injection and its effective constituent luteoloside protect against sepsis partly via inhibition of HMGB1/TLR4/NF-κB/MAPKs signaling pathways

ETHNOPHARMACOLOGICAL RELEVANCE

Reduning injection (RDN), a popular traditional Chinese medicine, formulated by three herbs (i.e., Artemisia carvifolia Buch.-Ham. ex Roxb., Lonicera japonica Thunb., and Gardenia jasminoides J. Ellis), has been widely used to treat upper respiratory infectious diseases in China.

AIM OF THE STUDY

To investigate the protective effect of RDN on both lipopolysaccharides (LPS)- and cecal ligation and puncture (CLP)-induced septic mice. To identify the potentially effective constituent, and to determine its protective effect and underlying mechanism in vivo and in vitro.

MATERIALS AND METHODS

Male C57BL/6 mice were used to establish septic model by tail intravenous injection of 4 mg/kg LPS or CLP surgery. After modeling, mice were administered by tail intravenous injection of RDN in the dose of 16 or 8 mL/kg/day. The mortality, histopathology, plasma levels of inflammatory cytokines were evaluated respectively. In addition, we screened the potentially effective substances of RDN against sepsis by detecting the nitric oxide (NO) production in LPS-stimulated Raw 264.7 cells and verified the effect of luteoloside in CLP-induced septic mice subsequently. Finally, the underlying mechanisms of RDN and luteoloside were investigated in the inflammatory model in vitro.

RESULTS

Administration of RDN significantly reduced the mortality and increased the survival rate in both LPS- and CLP-induced septic mice. Meanwhile, RDN reduced the release of inflammatory cytokines accompanied by alleviating the organs damage of lung, liver, and kidney in CLP-induced septic mice. Moreover, several components from Gardenia jasminoides J. Ellis extract (ZZ) or Lonicera japonica Thunb and Artemisia carvifolia Buch.-Ham. ex Roxb extract (JQ) as well as the constituents of luteoloside, quercetin, and caffeic acid were screened out to have obvious anti-inflammatory activity, which may be the potentially effective substances of RDN against sepsis. We further verified the protective role of luteoloside in CLP-induced septic mice. In addition, RDN and luteoloside significantly inhibited both the secretion and translocation of mobility group box (HMGB)1, and HMGB1-mediated activation of TLR4/NF-κB/MAPKs signaling pathways.

CONCLUSION

RDN and its effective constituent luteoloside exhibited a significant protective effect against sepsis, which were potential candidate drugs for treatment of sepsis. The mechanism of antisepsis partly was related to inhibition of HMGB1/TLR4/NF-κB/MAPKs signaling pathways. The results provide an evidence base for the follow-up clinical application of RDN in treatment of sepsis.

Topical application of Chinese herbal medicine DAEP relieves the osteoarthritic knee pain in rats

Background

The potential adverse effects of conventional oral pharmacotherapy of osteoarthritis (OA) restrict their long-term use. Topical application of a Chinese herbal paste for relieving OA knee pain can be effective and safe. However, evidence-based scientific research is insufficient to support its application worldwide. The aim of this study was to investigate the in vivo efficacy of a topical Chinese herbal paste on relieving OA knee pain and its underlying mechanism.

Methods

An OA rat model was developed by anterior cruciate ligament transection (ACLT) followed by treadmill running. A herbal paste including Dipsaci Radix, Achyranthis Bidentatae Radix, Eucommiae Cortex and Psoraleae Fructus, named as DAEP, was applied topically on the knee joint of the rats (DAEP). The rats without DAEP treatment served as Control. Rats with surgery but without ACLT, treadmill running and DAEP treatment acted as Sham. The morphologic change of the knee joint was observed radiographically. Nociception from the knee of the rats was assessed using Incapacitent test and CatWalk gait system. The therapeutic mechanism was investigated by analyzing the gene and protein expression of inflammatory markers via qPCR and Western blot, respectively.

Results

Radiographic images showed less destruction at the posterior tibial plateau of the DAEP group compared with the Control after 2 weeks of treatment. The static weight ratio and the gait parameters of the Control were reduced significantly via Incapacitance test and CatWalk gait analysis, respectively. DAEP treatment increased the Print Area and Maximum Intensity significantly compared with the Control. DAEP significantly suppressed the upregulation of gene expression of interleukin (IL)-6, tumor necrosis factor (TNF)-α, and inducible nitric oxide synthase (iNOS).

Conclusions

DAEP exhibited its effect via the nuclear factor (NF)-κB pathway by suppressing the phosphorylation of IκB kinase αβ (p-IKKαβ) and cyclooxygenase-2 (COX-2) protein expression. This study provides scientific evidence to support the clinical application of the Chinese herbal paste on reliving OA pain.

Traditional tonifying polyherbal infusion, Jatu-Phala-Tiga, exerts antioxidant activities and extends lifespan of Caenorhabditis elegans

Background

The imbalance between the generation of free radicals and natural cellular antioxidant defenses, known as oxidative stress, can cause oxidation of biomolecules and further contribute to aging-associated diseases. The purpose of this study was to evaluate the antioxidant capacities of Thai traditional tonifying preparation, Jatu-Phala-Tiga (JPT) and its herbal ingredients consisting of Phyllanthus emblica, Terminalia arjuna, Terminalia chebula, and Terminalia bellirica and further assess its effect on longevity.

Method

Antioxidant activities of various extracts obtained from JPT and its herbal components were carried out using well-established methods including metal chelating, free radical scavenging, and ferric reducing antioxidant power assays. Qualitative analysis of the chemical composition from JPT water extract was done by high-performance liquid chromatography tandem with electrospray ionisation mass spectrometry. The effect of JPT water extract on the lifespan of Caenorhabditis elegans were additionally described.

Results

Among the extracts, JPT water extract exerted remarkable antioxidant activities as compared to the extracts from other solvents and individual constituting plant extract. JPT water extract was found to possess the highest metal chelating activity, with an IC₅₀ value of 1.75 ± 0.05 mg/mL. Moreover, it exhibited remarkable scavenging activities towards DPPH, ABTS, and superoxide anion radicals, with IC₅₀ values of 0.31 ± 0.02, 0.308 ± 0.004, and 0.055 ± 0.002 mg/mL, respectively. The ORAC and FRAP values of JPT water extract were 40.338 ± 2.273 μM of Trolox/μg of extract and 23.07 ± 1.84 mM FeSO₄/mg sample, respectively. Several well-known antioxidant-related compounds including amaronols, quinic acid, gallic acid, fertaric acid, kurigalin, amlaic acid, isoterchebin, chebulagic acid, ginkgolide C, chebulinic acid, ellagic acid, and rutin were found in this extract. Treatment with JPT water extract at 1 and 5 mg/mL increased C. elegans lifespan under normal growth condition (7.26 ± 0.65 vs. 10.4 0± 0.75 (p < 0.01) and 10.00 ± 0.73 (p < 0.01) days, respectively).

Conclusions

The results indicated that JPT and its herbal ingredients exhibited strong antioxidant activities, in particular the water extract of the polyherbal tonic. These findings rationalize further investigation in JPT infusion as a promising agent for anti-aging and oxidative stress prevention.

Pharmacokinetics study of 16 representative components from Baoyuan Decoction in rat plasma by LC-MS/MS with a large-volume direct injection method

BACKGROUND

Baoyuan decoction (BYD), a well-known traditional Chinese medicine (TCM) formula, is clinically used for the treatment of aplastic anemia, chronic renal failure, coronary heart disease, etc. PURPOSE: The purpose of this study was to develop a large-volume direct injection liquid chromatography-mass spectrometry (LC-MS) method for simultaneous determination of 16 representative flavonoids and saponins in rat plasma after oral administration of BYD.

METHODS

The rat plasma sample was injected directly into a pre-column, which was eluted firstly by 0.05% formic acid in water. Then, the accumulated components were eluted from the pre-column and transferred into a Waters BEH C18 column with acetonitrile and water system (contain 0.05% formic acid) as the mobile phase at a rate of 0.3 ml/min. The detection was accomplished in a negative mode using the schedule multiple-reaction monitoring (sMRM).

RESULTS

The correlation coefficients for calibration curves were all higher than 0.9920 for formononetin, ononin, calycosin, liquiritigenin, isoliquiritigenin, glycyrrhizic acid, glycyrrhetinic acid, liquiritin, isoliquiritin, liquiritin apioside, isoliquiritin apioside, ginsenoside Rb1, ginsenoside Re, ginsenoside Rd, ginsenoside Rg1 and astragaloside. The intra- and inter-day precisions (RSD) and accuracy (RE) for the investigated components were in the range of -10.9 to 13.7%. The average recoveries were in the range of 75.7-108.6%. This method was successfully applied to investigate the pharmacokinetics of 16 compounds of BYD in rats. The absorption and elimination rates of the representative saponins were significantly slower than most of the targeted-flavonoids after oral administration of BYD in rats.

CONCLUSION

The results demonstrated that the large-volume direct injection LC-MS method provided a rapid and efficient approach for multi-components pharmacokinetics of TCM.

A Comprehensive and Rapid Quality Evaluation Method of Traditional Chinese Medicine Decoction by Integrating UPLC-QTOF-MS and UFLC-QQQ-MS and its Application

Decoction is one of the oldest forms of traditional Chinese medicine and it is widely used in clinical practice. However, the quality evaluation and control of traditional decoction is a challenge due to the characteristics of complicated constituents, water as solvent, and temporary preparation. ShenFu Prescription Decoction (SFPD) is a classical prescription for preventing and treating many types of cardiovascular disease. In this article, a comprehensive and rapid method for quality evaluation and control of SFPD was developed, via qualitative and quantitative analysis of the major components by integrating ultra-high-performance liquid chromatography equipped with quadrupole time-of-flight mass spectrometry and ultra-fast-performance liquid chromatography equipped with triple quadrupole mass spectrometry. Consequently, a total of 39 constituents were tentatively identified in qualitative analysis, of which 21 compounds were unambiguously confirmed by comparing with reference substances. We determined 13 important constituents within 7 min by multiple reaction monitoring. The validated method was applied for determining five different proportion SFPDs. It was found that different proportions generated great influence on the dissolution of constituents. This may be one of the mechanisms for which different proportions play different synergistic effects. Therefore, the developed method is a fast and useful approach for quality evaluation of SFPD.

Systems-Mapping of Herbal Effects on Complex Diseases Using the Network-Perturbation Signatures

The herbs have proven to hold great potential to improve people's health and wellness during clinical practice over the past millennia. However, herbal medicine for the personalized treatment of disease is still under investigation owing to the complex multi-component interactions in herbs. To reveal the valuable insights for herbal synergistic therapy, we have chosen Traditional Chinese Medicine (TCM) as a case to illustrate the art and science behind the complicated multi-molecular, multi-genes interaction systems, and how the good practices of herbal combination therapy are applicable to personalized treatment. Here, we design system-wide interaction map strategy to provide a generic solution to establish the links between diseases and herbs based on comprehensive testing of molecular signatures in herb-disease pairs. Firstly, we integrated gene expression profiles from 189 diseases to characterize the disease-pathological feature. Then, we generated the perturbation signatures from the huge chemical informatics data and pharmacological data for each herb, which were represented the targets affected by the ingredients in the herb. So that we could assess the effects of herbs on the individual. Finally, we integrated the data of 189 diseases and 502 herbs, yielding the optimal herbal combinations for the diseases based on the strategy, and verifying the reliability of the strategy through the permutation testing and literature verification. Furthermore, we propose a novel formula as a candidate therapeutic drugs of rheumatoid arthritis and demonstrate its therapeutic mechanism through the systematic analysis of the influencing targets and biological processes. Overall, this computational method provides a systematic approach, which blended herbal medicine and omics data sets, allowing for the development of novel drug combinations for complex human diseases.

Simultaneous Determination of Phenobarbital, Pentobarbital, Amobarbital and Secobarbital in Raw Milk via Liquid Chromatography with Electron Spray Ionization Tandem Mass Spectrometry

A rapid, sensitive and specific liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed for the simultaneous determination of four barbiturates (phenobarbital, pentobarbital, amobarbital and secobarbital) in raw milk. The barbiturates were extracted using liquid-liquid extraction, ultrasonication and centrifugation, and purified on an SPE column. Analytes were separated by HPLC on a CSH C18 column eluted using an acetonitrile-water system with a linear gradient dilution programme, and detected by MS/MS. The recoveries of the barbiturates were 85.0-113.5%, and the intra- and inter-assay RSDs were less than 9.8% and 7.3%, respectively. The limit of detection was 5 ng/mL for all four of the barbiturates. The analytical method exhibited good linearity from 10 to 1000 ng/mL; the correlation coefficient (r²) was greater than 0.9950 for each barbiturate. This method was also applied to the determination of barbiturates in real milk samples and was found to be suitable for the determination of veterinary drug residues in raw milk.