The quality evaluation system of a famous traditional Chinese medicine Huaganjian decoction was established.

Huaganjian decoction (HGJD) has been widely used clinically to treat liver injuries and gastritis. However, the quality evaluation system for HGJD is not perfect. In this study, paeoniflorin, hesperidin, geniposide, naringin, and quercetin were employed as quality markers. The quantitative analysis of these five components in HGJD was conducted using a high-performance liquid chromatography coupled with triple quadrupole tandem mass spectrometry method. This method underwent validation for linearity, precision, accuracy, repeatability, and recovery. In summary, a reliable quantitative method was successfully employed to establish a comprehensive quality evaluation of HGJD.

A Big Coal Block Alarm Detection Method for Scraper Conveyor Based on YOLO-BS.

With the aim of solving the problem of coal congestion caused by big coal blocks in underground mine scraper conveyors, in this paper we proposed the use of a YOLO-BS (YOLO-Big Size) algorithm to detect the abnormal phenomenon of coal blocks on scraper conveyors. Given the scale of the big coal block targets, the YOLO-BS algorithm replaces the last layer of the YOLOv4 algorithm feature extraction backbone network with the transform module. The YOLO-BS algorithm also deletes the redundant branch which detects small targets in the PAnet module, which reduces the overall number of parameters in the YOLO-BS algorithm. As the up-sampling and down-sampling operations in the PAnet module of the YOLO algorithm can easily cause feature loss, YOLO-BS improves the problem of feature loss and enhances the convergence performance of the model by adding the SimAM space and channel attention mechanism. In addition, to solve the problem of sample imbalance in big coal block data, in this paper, it was shown that the YOLO-BS algorithm selects focal loss as the loss function. In view of the problem that the same lump coal in different locations on the scraper conveyor led to different congestion rates, we conducted research and proposed a formula to calculate the congestion rate. Finally, we collected 12,000 image datasets of coal blocks on the underground scraper conveyor in Daliuta Coal Mine, China, and verified the performance of the method proposed in this paper. The results show that the processing speed of the proposed method can reach 80 fps, and the correct alarm rate can reach 93%. This method meets the real-time and accuracy requirements for the detection of abnormal phenomena in scraper conveyors.

An Online Calibration Method for a Galvanometric System Based on Wavelet Kernel ELM.

The online calibration method of a two-dimensional (2D) galvanometer requires both high precision and better real-time performance to meet the needs of moving target position measurement, which presents some challenges for traditional calibration methods. In this paper, a new online calibration method is proposed using the wavelet kernel extreme learning machine (KELM). Firstly, a system structure is created and its experiment setup is established. The online calibration method is then analyzed based on a wavelet KELM algorithm. Finally, the acquisition methods of the training data are set, two groups of testing data sets are presented, and the verification method is described. The calibration effects of the existing methods and wavelet KELM methods are compared in terms of both accuracy and speed. The results show that, for the two testing data sets, the root mean square errors (RMSE) of the Mexican Hat wavelet KELM are reduced by 16.4% and 38.6%, respectively, which are smaller than that of the original ELM, and the standard deviations (Sd) are reduced by 19.2% and 36.6%, respectively, indicating the proposed method has better generalization and noise suppression performance for the nonlinear samples of the 2D galvanometer. Although the online operation time of KELM is longer than ELM, due to the complexity of the wavelet kernel, it still has better real-time performance.

An Improved Method for Spot Position Detection of a Laser Tracking and Positioning System Based on a Four-Quadrant Detector.

For the laser tracking and positioning system of a moving target using a four-quadrant detector, the accuracy of laser spot position detection has a serious impact on the tracking performance of the system. For moving target tracking, the traditional spot position detection method of a four-quadrant detector cannot give better consideration to both detection accuracy and operation speed. In view of this, an improved method based on piecewise low-order polynomial least squares fitting and a Kalman filter is proposed. Firstly, the tracking and positioning mathematical model of the system is created, and the experimental device is established. Then, the shortcomings of traditional methods are analyzed, and the improved method and the real-time tracking and positioning algorithm of the system are studied. Finally, through the experiment, the system operation effects are compared and analyzed before and after the improvement. The experimental results of system dynamic tracking show that, the least squares fitting of the experimental data using a 5-segment and quadratic polynomial can achieve better results. By using the improved method, the maximum tracking distance of a moving object is increased from 12 m to more than 30 m. At a distance of 7.5 m, the maximum tracking speed can reach 2.11 m/s, and the root mean square error (RMSE) of the position is less than 4.59 mm. At 15.5 m, the maximum tracking speed is 2.04 m/s and the RMSE is less than 5.42 mm. Additionally, at 23.5 m, it is 1.13 m/s and 5.71 mm.

Tissue Distribution and Anti-Lung Cancer Effect of 10-Hydroxycamptothecin Combined with Platycodonis Radix and Glycyrrhizae Radix ET Rhizoma.

10-Hydroxycamptothecin (HCPT) is a broad-spectrum chemotherapeutic drug, although its side effects and multidrug resistance (MDR) limit its clinical application. A range of drug delivery systems have been utilized to overcome its shortcomings and maintain its therapeutic efficacy, however the use of the transport effect of traditional Chinese medicines (TCMs) to improve the distribution of chemotherapeutic drugs has not been widely reported. Platycodonis Radix (JG) and Glycyrrhizae Radix ET Rhizoma (GC) are common TCMs in clinics and are often combined as drug pairs to act as "transport agents". In the present study, the effect of JG and GC (JGGC) on the distribution of HCPT in tissues and its antitumor efficacy after being combined as a therapy were investigated, for which ultrahigh-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) was used. Furthermore, the effect on the protein expression of multidrug resistance proteins (P-gp and LRP), and the immunomodulatory and synergistic antiapoptotic effect on Lewis lung cancer-bearing C57BL/6J mice were also evaluated. The results demonstrate that JGGC significantly increased the area under the concentration time curve (AUC) and mean residence time (MRT) and reduced the clearance rate (CL) of HCPT. In addition, the combined use of JGGC decreased the levels of LRP, P-gp and Bcl-2/Bax when treated with HCPT. JGGC also significantly elevated the levels of RBCs, PLTs, HGB, IL-2, and IFN-γ, and decreased IL-10 levels. In summary, an increased concentration of HCPT in tissues was observed when it was combined with JGGC through inhibition of efflux protein, with a synergistic enhancement of the anticancer effect observed through promotion of apoptosis and immunity due to a reversion of the Th1/Th2 shift. Our findings provide a reference for the feasibility of combining JGGC with chemotherapy drugs in clinical applications.

Constituents and Anti-Hyperuricemia Mechanism of Traditional Chinese Herbal Formulae Erding Granule.

Erding granule (EDG) is a traditional Chinese medicine that has recently been identified as having anti-hypouricemic effects. However, the active components and underlying mechanism for this new indication have not been elucidated. Therefore, we compared the effects of different EDG extracts (water, 50% ethanol and 95% ethanol) on serum uric acid concentrations in the hyperuricemia model mouse. We also analyzed the constituents of different extracts by ultra-high performance liquid chromatography combined with electrospray ionization quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS/MS) to observe the variation between the active and inactive products. Extract activity and target site were evaluated by assessing uric acid- and inflammation-suppressing effects along with evaluating ability to regulate the uric acid transporter. The results showed that the 50% ethanol extract (EDG-50) had an obvious serum uric acid concentration lowering effect compared with water (EDG-S) and the 95% ethanol extract (EDG-95). UHPLC-Q-TOF-MS/MS analysis showed that EDG-50 was compositionally different to EDG-S and EDG-95. EDG-50 showed dose-dependent effects on reducing uric acid, suppressing inflammation and regulating uric acid transporters. Moreover, western blot analysis showed that EDG-50 down-regulated GLUT9 and URAT1 expression, and up-regulated OAT1 expression. Therefore, our findings enable the preliminarily conclusion that EDG-50 lowers serum uric acid concentrations, mainly by down-regulating the expression of GLUT9 and URAT1 proteins and up-regulating the expression of OAT1 proteins. This provides a research basis for clinical use of EDG as an anti-hyperuricemic agent.

Isolation and Identification of the Anti-Oxidant Constituents from Loropetalum chinense (R. Brown) Oliv. Based on UHPLC⁻Q-TOF-MS/MS.

The aim of this study was to identify the chemical constituents of Loropetalum chinense (R. Brown) Oliv. (LCO) and determine which of these had antioxidant effects. The chemical composition of a 70% ethanol extract of LCO was analyzed systematically using UHPLC⁻Q-TOF-MS/MS. The chemical components of the 70% ethanol extract of LCO were then separated and purified using macroporous resin and chromatographic techniques. Antioxidant activity was evaluated using a DPPH assay. In total, 100 compounds were identified tentatively, including 42 gallic acid tannins, 49 flavones, and 9 phenolic compounds. Of these, 7 gallium gallate, 4 flavonoid and 8 quinic acid compounds were separated and purified from the 70% ethanol extract of LCO. The compounds identified for the first time in LCO and in the genus Loropetalum were 3,4,5-trimethoxyphenyl-(6'-O-galloyl)-O-ß-d-glucopyranoside, protocatechuic acid, ethyl gallate, 5-O-caffeoylquinic acid, 3-O-caffeoylquinic acid, 3,5-O-diocaffeoylquinic acid, 4,5-O-diocaffeoylquinic acid and 3,4-O-diocaffeoylquinic acid. The 50% inhibitory concentration (IC50) values of compounds 1,2,3,4,6-penta-O-galloyl-ß-d-glucose, gallic acid, protocatechuic acid, and ethyl gallate were 1.88, 1.05, 1.18, and 1.05 µg/mL, respectively. Compared with the control group (VC) (2.08 µg/mL), these compounds exhibited stronger anti-oxidation activity. This study offered considerable insight into the chemical composition of LCO, with preliminary identification of the antioxidant ingredients.

[Quantitative analysis of phenolic acids in ainsliaea fragrans from different habitats].

OBJECTIVE: The contents of major phenolic acids in Ainsliaea fragrans from different habitats were determined,in order to improve quality standards of Ainsliaea fragrans and provide reference for optimization its daodi habitat. METHODS: Separation and determination of two kinds of phenolic acids, caffeoylquinic acids (CQA)and dicaffeoylquinic acid (DCQA), in Ainsliaea fragrans were carried out by RP-HPLC with Cosmosil RP-C18 column (250 mm x 4.6 mm, 5 µm), acetonitrile-0.1% formic acid solution as mobile phase at the flow rate of 1.0 mL/min, detection wavelength at 328 nm and column temperature at 35 °C. RESULTS: CQA and DCQA were uneven in Ainsliaea fragrans from different habitats. In the sample from Wuyuan, Jiujiang and Shangrao in Jiangxi, the contents of phenolic acids were higher than those from other habitats significantly. The sample from Guangxi habitat had the lowest phenolic acids content. And the chlorogenic acid and 3,5-DCQAs' percentage were higher than other phenolic acids. CONCLUSION: This method is accurate and easy with good repeatability, which can be used in determination of eight phenolic acids in Ainsliaea fragrans from different habitats. Ainsliaea fragrans in Jiangxi Province has good qulity.

Exploration of the anti-hyperuricemia effect of TongFengTangSan (TFTS) by UPLC-Q-TOF/MS-based non-targeted metabonomics.

BACKGROUND: TongFengTangSan (TFTS) is a commonly used Tibetan prescription for gout treatment. Previously, TFTS (CF) was confirmed to have a significant uric acid-lowering effect. However, the anti-hyperuricemia mechanisms and the main active fractions remain unclear. The current study aimed to investigate the anti-hyperuricemia mechanism using metabolomics and confirm the active CF fraction. METHODS: The hyperuricemia model was established through intraperitoneal injection containing 100 mg/kg potassium oxonate and 150 mg/kg hypoxanthine by gavage. We used serum uric acid (sUA), creatinine (CRE), blood urea nitrogen (BUN), xanthine oxidase (XOD) activity, interleukin-6 (IL-6) and interleukin-1ß (IL-1ß) as indicators to evaluate the efficacy of CF and the four fractions (SX, CF30, CF60, and CF90). The anti-hyperuricemia mechanism of CF was considered through non-targeted metabolomics depending on the UPLC-Q-TOF-MS technology. Principle component analysis (PCA) and orthogonal partial least squares-discriminant analysis (OPLS-DA) helped explore the potential biomarkers in hyperuricemia. Moreover, the differential metabolites and metabolic pathways regulated by CF and four fractions were also assessed. RESULTS: CF revealed a significant anti-hyperuricemia effect by down-regulating the level of sUA, sCRE, sIL-1ß, and XOD. SX, CF30, CF60, and CF90 differed in the anti-hyperuricemia effect. Only CF60 significantly lowered the sUA level among the four fractions, and it could be the main efficacy fraction of TFTS. Forty-three differential metabolites were identified in hyperuricemia rats from plasma and kidney. Pathway analysis demonstrated that seven pathways were disrupted among hyperuricemia rats. CF reversed 19 metabolites in hyperuricemia rats and exerted an anti-hyperuricemia effect by regulating purine metabolism. CF60 was the main active fraction of TFTS and exerted a similar effect of CF by regulating purine metabolism. CONCLUSIONS: CF and CF60 could exert an anti-hyperuricemia effect by regulating the abnormal purine metabolism because of hyperuricemia while improving intestinal and renal function. CF60 could be the main active fraction of TFTS.

Analysis of phytochemical components of Tibetan medicine Pedicularis flava and Pedicularis muscicola by GC-MS and UHPLC-TOF-MS.

Traditional medicine, 'LuRu', is a commonly used Tibetan medicine for clearing away heat and detoxifying. Dried products of Pedicularis flava and Pedicularis muscicola are often used as 'LuRu' in the market. This study aims to compare the chemical constituents of P. flava and P. muscicola using GC-MS and UPLC-TOF-MS, and confirm which plant species is more suitable to be used as 'LuRu'. A total of 46 and 68 compounds were identified from the volatile and non-volatile components, respectively. Out of these, 17 and 37 volatile and non-volatile components, respectively, had pharmacological activities. P. flava showed a higher content of the same active components than P. muscicola. Good biological activities are only observed in the unique components in P. flava, and not in P. muscicola. The two herbs should not be mixed in clinical medication. Our study shows that P. flava is better suited as a high-quality herb for the Tibetan medicine, 'LuRu'.

Volatile components of Tibetan Pedicularis flava and Pedicularis muscicola were analysed for the first timewiooi.Non-volatile components of Tibetan Pedicularis flava and Pedicularis muscicola were analysed for the first time.Differences in chemical composition and content between Pedicularis flava and Pedicularis muscicola were studied.

Comprehensive chemical profiling of the flowers of Citrus aurantium L. var. amara Engl. and uncovering the active ingredients of lipid lowering.

The flowers of Citrus aurantium L. var. amara Engl. (FCAVA) is popularly consumed as an edible tea for anti-hyperlipidemia. But the active ingredients are not fully clear. In this study, ultra-high performance liquid chromatography coupled to quadrupole time of flight tandem mass spectrometry (UHPLC-QTOF-MS/MS) with diagnostic product ions and neutral loss filtering strategy were successfully used for comprehensive characterization of chemical components in FCAVA. A total of 228 constituents, including 46 organic acids, 12 coumarins and 170 flavonoids, were tentatively characterized (30 confirmed with reference standards). Among them, nineteen flavonoids in 70 batches of FCAVA from different geographical origins were quantified by UHPLC tandem triple quadrupole mass spectrometry (QQQ-MS), which displayed satisfactory linearity, sensitivity, precision, accuracy, and stability. According to analytical results, the distribution of nineteen flavonoids in different geographical origins of FCAVA was clarified. In addition, the effect on LDL uptake of twenty-five flavonoids was investigated in HepG2 cell. It was found that the acacetin, diosmetin and rutin dose-dependently enhanced LDL uptake in HepG2 cells comparing to control. Furthermore, in a hyperlipidemia C57BL/6J mice model, administration of acacetin, diosmetin and rutin (30 mg/kg/d, intragastric, for three weeks) significantly decreased the levels of total cholesterol (TC), triglyceride (TG) and low density lipoprotein cholesterol (LDL-C) in plasma, respectively. Overall, these findings indicated the potential of FCAVA in the development of functional food or medicine for the prevention and treatment of hyperlipidemia, which could be considered for the improvement of quality standardization of FCAVA.

Jiegeng Decoction Potentiates the Anticancer Efficacy of Paclitaxel in vivo and in vitro.

Paclitaxel (PTX) has been the first-line treatment for lung cancer; however, its clinical use is limited due to multidrug resistance (MDR) and adverse effects. Thus, there is an urgent need to explore agents that can enhance the anticancer efficacy of PTX by reducing drug resistance and adverse reactions. Jiegeng decoction (JG) was used as the meridian guide drug and adjuvant drug in treatment of lung cancer. However, the mechanism of adjuvant effect was unclear. The aim of this study was to determine whether JG could potentiate the anticancer effect of PTX. Tissue distribution of PTX was detected using HPLC-MS/MS. The anti-lung cancer effect of the combination of PTX and JG in Lewis lung cancer C57BL/6J mice was evaluated based on the body weight and tumor-inhibition rate. PTX concentration in tumors was determined using HPLC-MS and in vivo imaging. Biochemical indices were detected using biochemical analyzer and ELISA. The anticancer mechanism of the PTX-JG combination in A549/PTX cells was elucidated based on cell proliferation, annexin V-FITC apoptosis assay, and western blotting. Tissue distribution analysis showed that the distribution of PTX increased in the lungs, liver, and heart upon administering the combination of PTX and JG. JG remarkably enhanced the anticancer effect of PTX by increasing the red blood cell and platelet counts; increasing hemoglobin, interleukin (IL)-2, and tumor necrosis factor-α levels; increasing CD4+T cells and the CD4+/CD8+ ratio; and decreasing IL-10 levels. JG administration led to the increased distribution of PTX at the tumor lesion sites and also potentiated the anticancer effect of PTX by inhibiting tumor cell proliferation and promoting apoptosis. Moreover, JG reversed PTX resistance by inhibiting the expression of lung resistance-related proteins, multiresistance protein 1, P-glycoprotein, and breast cancer-resistant protein. Furthermore, the combination of JG and PTX decreased alanine aminotransferase and aspartate aminotransferase levels and did not affect creatine kinase-MB levels. Therefore, our discovery suggests that JG increased the anticancer effect of PTX by downregulating the MDR-related protein and demonstrated a synergistic enhancement of immunity. Thus, the combination of PTX with JG shows potential in the management of lung cancer owing to its synergistic and detoxifying effects.

[Study on antibacterial active components from Viola yedoensis].

OBJECTIVE: Study on the antibacterial activity of Viola yedoensis and the antibacterial active compounds. METHOD: The chemical compositions were isolated by means of solvent extraction, column chromatography on silica gel, sephadex LH-20 and crystallization. The antibacterial activities were tested by Neo-Sensitab disk-diffusion method, nephelometric analysis and plating method. RESULT: One new compound (4) along with three known compounds were isolated from this plant for the first time and were identified as aesculetin (1), 6,7-dimethoxycoumarin (2), scopoletin (3) and 5-methoxy-7-hydroxymethylcoumarin (4), respectively. All the compounds showed antibacterial and antibactericidal activities at varying degree on Streptococcus Aureas, S. agalactiae, S. uberis, S. dysgalactiae, E. coli and Salmonella, of which 1 was most active with 0.031- 0.313 g x L(-1) of minimal inhibitory concentrations (MIC) and 0.313 - 0.625 g x L(-1) of minimal bactericidal concentrations (MBC). CONCLUSION: Viola yedoensis has a broad spectrum of antibacterial activity on animal pathogenic bacteria, and coumarins may be the main antibacterial activity ingredients.

Study on anti-hyperuricemia effects and active ingredients of traditional Tibetan medicine TongFengTangSan (TFTS) by ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry.

TongFengTangSan (TFTS), a traditional Tibetan medicine comprising of Tinospora sinensis (TS), Terminalia chebula Retz (TC) and Trogopterori faeces (TF), is used to treat joint diseases like gout, gout arthritis, swelling, pain etc. Despite the significant therapeutic effects of TFTS, its pharmacological components have not been analyzed so far. Therefore, the chemical composition of the effective part of TFTS was analyzed by ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS/MS). The results show that the ethanol extract (EE) of TFTS was more effective in reducing the serum uric acid (SUA) and XOD (Serum and Liver) levels in a hyperuricemic rats model compared to the TFTS raw powder (RP). UHPLC-Q-TOF-MS/MS identified a total of 106 compounds in the positive and negative ion mode, of which 87 were from TC, 13 from TS and 6 from TF. In addition, 106 compounds contained 57 tannins, 6 triterpenoids, 10 alkaloids, 7 flavonoids, 22 organic acids and 4 phenylpropanoids. The preliminary results indicate that the EE of TFTS includes the active anti hyperuricemic substances. The present study first investigated the efficacy and the active components of TFTS in hyperuricemic treatment, and further summarized the diagnostic ion and neutral loss patterns of MS/MS cracking of tannic compounds. These findings lay the foundation for the further study and clinical application of TFTS.

Identification and Quantification Analysis on the Chemical Constituents from Traditional Mongolian Medicine Flos Scabiosae Using UHPLC-DAD-Q-TOF-MS Combined with UHPLC-QqQ-MS.

In this study, a systematic method was established for the qualitative and quantitative analysis of the major constituents in Flos Scabiosae (FS). First, Ultra-high performance liquid chromatography tandem quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS) was developed for the identification of the multi-constituents in FS. A total of 48 compounds (9 phenolic acids, 24 flavonoids, 8 iridoids and 7 others) were unambiguously or tentatively identified, including 25 compounds (flavonoids, phenolic acids) identified in FS for the first time. Second, ultra-high performance liquid chromatography combined with triple quadrupole mass spectrometry (UHPLC-MS-MS) was developed for the quantitative analysis of 10 phenolic compounds. Ten compounds, either with high contents or strong bioactivities, were chosen as markers. This analytical method was validated through intra- and inter-day precision, repeatability and stability, with respective relative standard deviations <4.43, <8.64, <4.60 and <3.65%, respectively. The limits of detection and quantification were <1.09 and <16.96 ng/mL, respectively. The overall recoveries ranged from 96.47 to 103.94% .Then the validated method was applied to determine 10 batches of FS. The results indicated that the new method can be applied for the qualitative and quantitative analysis of FS.

Esculetin as bioactive marker: towards a rational scientific approach for the treatment of hyperuricemia using Traditional Chinese Medicine

Traditional Chinese Herbal Medicine has been used to prevent and cure disease in China for thousands of years and has gained global interest in recent decades. The Erding formula is a Chinese Pharmacopeia (ChP)-listed herbal preparation used for treating sore throat, carbuncles and boils. Esculetin is a ChP quality control (QC) marker for these indications. A previous study found that a new indication, hyperuricemia, can be added to the Erding formula. Therefore, this study aimed to evaluate whether the traditionally used marker, esculetin, still has bioactivity for hyperuricemia, which is substantially different from the original indications. The study analyzed the quantity of esculetin by high-performance liquid chromatography, assessed the therapeutic effect of esculetin using animal model, and then characterized esculetin and its metabolites in serum via ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry. The results showed that the esculetin content in the aqueous Erding extract was 0.26±0.05% (w/w). Both the Erding extract and esculetin significantly reduced uric acid levels. Six metabolites of esculetin were identified in mice serum. This study revealed a rational scientific approach to prove esculetin is a reliable bioactive and QC marker for Erding formula in hyperuricemia treatment which contributed to ensure product quality and therapeutic efficacy.

Simultaneous quantification of polymethoxylated flavones and coumarins in Fructus aurantii and Fructus aurantii immaturus using HPLC-ESI-MS/MS.

The major lipid-soluble constituents in Fructus aurantii (zhiqiao) and Fructus aurantii immaturus (zhishi) are polymethoxylated flavones (PMFs) and coumarins. In the present study, a high-performance liquid chromatography with electrospray ionization tandem mass spectrometry method was developed to quantify PMFs (nobiletin, tangeretin, 5-hydroxy-6,7,8,4'-tetramethoxyflavone, and natsudaidai) and coumarins (marmin, meranzin hydrate, and auraptene) simultaneously. PMFs and coumarins were detected by electrospray ionization tandem mass spectrometry in positive ion mode and quantified with multiple reaction monitor. Samples were separated on a Diamonsil C18 (150 mm × 4.6 mm, 5 µm) column using acetonitrile and formic acid-water solution as a mobile phase in gradient mode with a flow rate at 0.5 mL/min. All calibration curves showed good linearity (r² > 0.9977) within the test ranges. Variations of the intraday and interday precisions were less than 4.07%. The recoveries of the components were within the range of 95.79%-105.04% and the relative standard deviations were less than 3.82%. The method developed was validated with acceptable accuracy, precision, and extraction recoveries and can be applied for the identification and quantification of four PMFs and three coumarins in citrus herbs.

High-performance liquid chromatography/tandem mass spectrometry for simultaneous determination of four dicaffeoylquinic acids in rat plasma.

A specific and reliable HPLC-MS/MS method was developed and validated for the simultaneous determination of four dicaffeoylquinic acids (DCQA): 3,4-DCQA, 1,5-DCQA, 3,5-DCQA and 4,5-DCQA. The analytes were separated on a C18 column (150 mm × 2.1 mm, 1.8 µm) and a triple-quadrupole mass spectrometry equipped with an electrospray ionization (ESI) source was applied for detection. The plasma sample was prepared by a liquid-liquid extraction method and the recovery for the four analytes was around 80%. The calibration curves were linear over a concentration range of 10.6-1060.0 ng/mL for 3,4-DCQA, 19.2-1920.0 ng/mL for 1,5-DCQA, 14.0-2900.0 ng/mL for 3,5-DCQA, 9.7-970.0 ng/mL for 4,5-DCQA. The intra-day and inter-day precision was less than 15% and the relative error (RE) were all within ±15%. The validated method was successfully applied to a pharmacokinetics study in rats after oral administration of the extracts of Ainsliaea fragrans cham (a traditional Chinese herb).