Evaluation of the inhibitory effect of quercetin on the pharmacokinetics of tucatinib in rats by a novel UPLC-MS/MS assay.

CONTEXT: Tucatinib (CYP2C8 substrate) and quercetin (CYP2C8 inhibitor) are two common drugs for the treatment of cancer. However, the effect of quercetin on the metabolism of tucatinib remains unknown. OBJECTIVE: We validated a sensitive method to quantify tucatinib levels in rat plasma based on ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS), which was successfully employed to explore the effect of quercetin on tucatinib pharmacokinetics in rats. MATERIALS AND METHODS: An Acquity UPLC BEH C18 column was applied to achieve the separation of tucatinib and internal standard (IS) talazoparib after protein precipitation with acetonitrile. Then, we used this assay to investigate the effect of different doses of quercetin (25, 50 and 100 mg/kg) on the exposure of orally administered tucatinib (30 mg/kg) in 24 Sprague-Dawley (SD) rats, which were randomly divided into three quercetin pre-treated groups and one control group (n = 6). RESULTS: Our developed assay was verified in all aspects of bioanalytical method validation, involving lower limit of quantification (LLOQ), selectivity, accuracy and precision, calibration curve, extraction recovery, matrix effect and stability. After pre-treatment with 100 mg/kg quercetin, AUC0→t, AUC0→∞ and Cmax of tucatinib were remarkably increased by 75.4%, 75.8% and 59.1% (p < 0.05), respectively, while CLz/F was decreased significantly by 47.3% (p < 0.05) when compared with oral administration of 30 mg/kg tucatinib alone. This change is dose-dependent. CONCLUSIONS: This study will help better understand the pharmacokinetic properties of tucatinib with concurrent use with quercetin, and more clinical verifications were inspired to confirm whether this interaction has clinical significance in humans.

Synthesis, Anticancer Screening of Some Novel Trimethoxy Quinazolines and VEGFR2, EGFR Tyrosine Kinase Inhibitors Assay; Molecular Docking Studies.

A new series of 8-methoxy-2-trimethoxyphenyl-3-substituted quinazoline-4(3)-one compounds were designed, synthesized, and screened for antitumor activity against three cell lines, namely, Hela, A549, and MDA compared to docetaxel as reference drug. The molecular docking was performed using Autodock Vina program and 20 ns molecular dynamics (MD) simulation was performed using GROMACS 2018.1 software. Compound 6 was the most potent antitumor of the new synthesized compounds and was evaluated as a VEGFR2 and EGFR inhibitor with (IC50, 98.1 and 106 nM respectively) compared to docetaxel (IC50, 89.3 and 56.1 nM respectively). Compounds 2, 6, 10, and 8 showed strong cytotoxic activities against the Hela cell line with IC50 of, 2.13, 2.8, 3.98, and 4.94 µM, respectively, relative to docetaxel (IC50, 9.65 µM). Compound 11 showed strong cytotoxic activity against A549 cell line (IC50, 4.03 µM) relative to docetaxel (IC50, 10.8 µM). Whereas compounds 6 and 9 showed strong cytotoxic activity against MDA cell line (IC50, 0.79, 3.42 µM, respectively) as compared to docetaxel (IC50, 3.98 µM).

Determination of fenazaquin in water and tomato matrices by GC-MS after a combined QuEChERS and switchable solvent liquid phase microextraction.

This study presents the use of Quick Easy Cheap Efficient Rugged and Safe (QuEChERS) as an effective sample cleaning procedure and switchable solvent liquid phase microextraction (SS-LPME) as a preconcentration tool for the determination of fenazaquin by gas chromatography mass spectrometry (GC-MS) at ultratrace levels. After a thorough optimization process, 0.50 mL of switchable solvent, 1.5 mL of 1.0 M sodium hydroxide, and 15 s of vortexing were determined as optimum conditions of the SS-LPME method. The limit of detection (LOD) and limit of quantitation (LOQ) determined using the optimum method (SS-LPME/GC-MS) were 0.05 and 0.18 ng/mL, respectively. Compared with direct GC-MS determination of fenazaquin, the optimum method yielded about 800-fold enhancement in detection power of GC-MS. The method was applied to lake, irrigation canal, well, and wastewater samples. In order to test the method's applicability on fresh tomato samples, a QuEChERS method was used before applying the SS-LPME method. Matrix-matched calibration standards were used to enhance the accuracy of fenazaquin quantification in spiked tomato samples to obtain recovery results close to 100%.

A quantitative LC-MS/MS method for determination of a small molecule agonist of EphA2 in mouse plasma and brain tissue.

Compound 27 {1, 12-bis[4-(4-amino-6,7-dimethoxyquinazolin-2-yl)piperazin-1-yl]dodecane-1,12-dione} is a novel small molecule agonist of EphA2 receptor tyrosine kinase. It showed much improved activity for the activation of EphA2 receptor compared with the parental compound doxazosin. To support further pharmacological and toxicological studies of the compound, a method using liquid chromatography and electrospray ionization tandem mass spectrometry (LC-MS/MS) has been developed for the quantification of this compound. Liquid-liquid extraction was used to extract the compound from mouse plasma and brain tissue homogenate. Reverse-phase chromatography with gradient elution was performed to separate compound 27 from the endogenous molecules in the matrix, followed by MS detection using positive ion multiple reaction monitoring mode. Multiple reaction monitoring transitions m/z 387.3 → 290.1 and m/z 384.1 → 247.1 were selected for monitoring compound 27 and internal standard prazosin, respectively. The linear calibration range was 2-200 ng/mL with the intra- and inter-day precision and accuracy within the acceptable range. This method was successfully applied to the quantitative analysis of compound 27 in mouse plasma and brain tissue with different drug administration routes.

Single-Molecule Force Measurement Guides the Design of Multivalent Ligands with Picomolar Affinity.

Interaction of multiple entities and receptors, or multivalency is widely applied to achieve high affinity ligands for diagnostic and therapeutic purposes. However, lack of knowledge on receptor distribution in living subjects remains a challenge for rational structure design. Herein, we develop a force measurement platform to probe the distribution and separation of the cell surface vascular endothelial growth factor receptors (VEGFR) in live cells, and use this to assess the geometry of appropriate linkers for distinct multivalent binding modes. A tetravalent lead ZD-4, which was developed from an antitumor drug ZD6474 (Vandetanib) with combined hybrid binding effects, yielded a 2000-fold improvement in the binding affinity to VEGFR with IC50 value of 25 pm. We confirmed the improved affinity by the associated increase of tumor uptake in the VEGFR-targeting positron emission tomography (PET) imaging using U87 tumor xenograft mouse model.

[Quantitative determination of febrifugine by proton nuclear magnetic resonance spectroscopy with internal standard method].

A quantitative nuclear magnetic resonance method(qNMR) was established for determination of the absolute content of febrifugine. Proton nuclear magnetic resonance spectroscopy of febrifugine was obtained in DMSO-d6 with hydroquinone as the internal standard substance on a Bruker Ascend 600 MHz superconducting nuclear resonance spectrometer at 298 K. The specific parameters were as follows: the observing frequency was 600 MHz,spectra width was 7 211 Hz, pulse width was 9.70 µs, pulse sequence was zg30,scan times was 32 and relaxation time was 2 s. The proton signal peaked at δ 7.71 for febrifugine and δ 6.55 for hydroquinone were selected as the quantification peaks. Linear regression of quantitative peak area ratio of febrifugine-hydroquinone versus their mass ratio yielded a correlation coefficient of 0.999 6 and a regression equation of Y=0.083 3X+0.008 6．The linear range of febrifugine was 2.17-17.07 g·L⁻¹,the precision RSD was 0.78%(n=6),the repeatability RSD was 1.2%(n=6),and the contents of three batches of febrifugine sample were 94.91%,95.09% and 95.52%,respectively. The content of febrifugine was 96.44% determined by high performance liquid chromatography(HPLC). The relative error of the content of febrigugine determinted by qNMR and HPLC methods was 1.27%. The results showed that the internal standard method of proton nuclear magnetic resonance spectroscopy could be used to determine the absolute content of febrifugine.

Phytochemical standardization of Vasicinein cough syrup by high performance liquid chromatography-densitometry.

The highly oriented modern detection techniques provide a precise and definite tool for investigation in natural medicines. Current study directed the standardization of eminent biomarker Vasicine in a natural cough syrup. A highly accurate and precise method of High-performance thin layer chromatography (HPTLC) has been developed to certify the quantity of vasicine inside the syrup. Ethyl acetate, chloroform, ethanol and ammonia (6:3:1: 1 v/v) were mobile phase for the study. The TLC plate silica gel G60F254 was used with CAMAG Scanner III and CAMAG Linomate 5. The detected Rf value was 0.51 in both sample and reference standard at 254 nm. International conference of Harmonization (ICH) guidelines were followed for the validation of the developed method. Linearity was achieved in the range of 200µg to 1600µg with co-efficient correlation r2=0.9995. Accuracy was found in between 98.9 to 101.4% however precision was good at both inter and intra-day. As per the standardization of ICH, the developed method was found to be reproducible and showed sharp similar peak with high resolution.

Utility of Hantzsch reaction for development of highly sensitive spectrofluorimetric method for determination of alfuzosin and terazosin in bulk, dosage forms and human plasma.

A highly sensitive, cheap, simple and accurate spectrofluorimetric method has been developed and validated for the determination of alfuzosin hydrochloride and terazosin hydrochloride in their pharmaceutical dosage forms and in human plasma. The developed method is based on the reaction of the primary amine moiety in the studied drugs with acetylacetone and formaldehyde according to the Hantzsch reaction, producing yellow fluorescent products that can be measured spectrofluorimetrically at 480 nm after excitation at 415 nm. Different experimental parameters affecting the development and stability of the reaction products were carefully studied and optimized. The fluorescence-concentration plots of alfuzosin and terazosin were rectilinear over a concentration range of 70-900 ng ml-1 , with quantitation limits 27.1 and 32.2 ng ml-1 for alfuzosin and terazosin, respectively. The proposed method was validated according to ICH guidelines and successfully applied to the analysis of the investigated drugs in dosage forms, content uniformity test and spiked human plasma with high accuracy.

A rapid ex vivo tissue model for optimising drug detection and ionisation in MALDI imaging studies.

The aim of this study was to establish an ex vivo model for a faster optimisation of sample preparation procedures, for example matrix choice, in matrix-assisted laser desorption/ionisation (MALDI) drug imaging studies. The ionisation properties of four drugs, afatinib, erlotinib, irinotecan and pirfenidone, were determined in an ex vivo tissue experiment by spotting decreasing dilution series onto liver sections. Hereby, the drug signals were distinctly detectable using different matrix compounds, which allowed the selection of the optimal matrix for each drug. The analysis of afatinib and erlotinib yielded high drug signals with α-cyano-4-hydroxycinnamic acid matrix, whereas 2,3-dihydroxybenzoic acid was identified as optimal matrix for irinotecan and pirfenidone detection. Our method was validated by a MALDI drug imaging approach of in vivo treated mouse tissue resulting in corresponding findings, indicating the spotting method as an appropriate approach to determine the matrix of choice. The present study shows the accordance between the detection of ex vivo spotted drugs and in vivo administered drugs by MALDI-TOF and MALDI-FT-ICR imaging, which has not been demonstrated so far. Our data suggest the ex vivo tissue spotting method as an easy and reliable model to optimise MALDI imaging measurements and to predict drug detection in tissue sections derived from treated mice prior to the recruitment of laboratory animals, which helps to save animals, time and costs.

Distribution study of tryptanthrin in rat tissues by HPLC and its relationship with meridian tropism of indigo naturalis in traditional Chinese medicine.

The aim of the present study is to characterize the distribution of tryptanthrin (TRYP) in rat tissues following oral administration at a dose of 100 mg/kg and its relationship with meridian tropism (MT) of indigo naturalis (IN) in traditional Chinese medicine (TCM). For quantitative analysis in biological samples, a sensitive, inexpensive and accurate high-performance liquid chromatographic method was developed and validated with 2-hydroxy acetophenone as internal standard, a Shimadzu C18 column and water-acetonitrile (55:45, v/v) as mobile phase. Acceptable intra-day and inter-day precision at high, medium and low concentration was acquired with RSD ranging from 0.87 to 5.22% and from 1.25 to 6.47%, respectively. Good assay and extraction recoveries were obtained with a single and relatively fast step to precipitate protein. The extraction recovery of TRYP ranged from 87.5 to 94.5 %. TRYP concentration was highest in the liver and remained for a much longer time than in other tissues. It could also be detected in kidney, lung, heart and spleen, but not in brain under the experimental conditions. The results confirmed the traditional knowledge of TCM that MT of IN belongs to the liver meridians and demonstrated that TRYP is one of the active constituents of the MT of IN.

Rapid and sensitive online determination of some selective α1-blockers by flow injection analysis with micelle-enhanced fluorescence detection.

A rapid, sensitive and selective flow injection analysis (FIA) method was developed for the determination of some selective α1-blockers including; terazosin (TER), doxazosin (DOX), prazosin (PRZ), and alfuzosin (ALF). The method was based on enhancement of the native fluorescence of the studied drugs in the presence of sodium dodecyl sulfate (SDS). The method was optimized for the buffer type, concentration and pH, surfactant type and concentration, flow rate and detection wavelengths in order to achieve the maximum sensitivity. The results showed that the best sensitivity was obtained by using SDS (10 mM) in phosphate buffer (20 mM, pH = 3), flow rate was 0.5 ml/min and the detector was set at λex = 250 and λem = 389. Under these optimum conditions there was a linear relationship between the concentration and the fluorescence intensity in the range from 5-400 ng ml(-) with correlation coefficient of more than 0.998. The detection and quantitation limits for the studied drugs by the proposed method were 3.2-11.9 ng ml(-1) and 10.8-39.7 ng ml(-1), respectively. The method was validated in accordance with the requirements of ICH guidelines and shown to be suitable for intended applications. Moreover, the binding constants for α1-blockers -SDS system were determined using the adduct model. The proposed method has been applied successfully for the analysis of the pure forms for studied drugs and also their pharmaceutical formulations and the results were compared with official methods.

Simultaneous determination of evodiamine and evodine in Beagle dog plasma using liquid chromatography tandem mass spectrometry.

A sensitive, rapid, and specific liquid chromatography/tandem mass spectrometry assay has been established and validated for the quantitation of evodiamine and evodine in Beagle dog plasma. Plasma samples of 0.2 ml were processed by liquid-liquid extraction with n-hexane/ethyl acetate (2:1, v/v). Chromatographic separations were done on a Symmetry C18 column (100 mm × 4.6 mm, ID, 5 µm) at 35°C with a linear gradient of methanol and 20 mM ammonium formate containing 0.2% formic acid. Evodiamine, evodine, and glibenclamide [internal standard (IS)] were ionized with an electrospray ionization source operated in positive ion mode. The MS/MS transitions were m/z 304.1 â†’ 161.1 for evodiamine, m/z 471.2 â†’ 425.1 for evodine, and m/z 494.1 â†’ 369.1 for IS. Calibration curves were linear over the concentration range of 0.1-100 ng/ml for evodiamine and 0.5-500 ng/ml for evodine. The mean extraction recoveries were 88.10 ± 3.21% for evodiamine and 81.24 ± 4.07% for evodine. The intra- and inter-day precisions were less than 11.10% and 12.81%, and the accuracy was within ± 11.76% for both analytes. Evodiamine and evodine were stable during storage and analytical periods. The validated method has been successfully applied to a pharmacokinetic study of evodiamine and evodine in beagle dogs after oral administration.

Direct, metal-free amination of heterocyclic amides/ureas with NH-heterocycles and N-substituted anilines in POCl3.

A POCl(3)-mediated, direct amination reaction of heterocyclic amides/ureas with NH-heterocycles or N-substituted anilines is described. Compared to the existing methods, this operationally simple protocol provides unique reactivity and functional group compatibility because of the metal-free, acidic reaction conditions. The yields are generally excellent.

Degradation studies of fenazaquin in soil under field and laboratory conditions.

Degradation of fenazaquin in sandy loam soil was investigated under field and laboratory conditions. Fenazaquin (Magister 10EC) was applied @ 125 and 250 g a.i./ha in field and in pot under field capacity moisture in laboratory. Samples drawn periodically were analyzed on GC-NPD. The residues of fenazaquin in both the doses and conditions dissipated almost 90% in 90 days. Half-life period were 32.04 and 31.35 days at two doses, respectively at field conditions and 30.10 and 28.94 days at laboratory conditions. Dissipation was approximated to first order kinetics in both conditions having correlation coefficient ranging from -0.9848 to -0.9914.

[Optimization of a HPLC determination method for Evodia rutaecarpa].

A HPLC method for determination of limonin, evodiamine and rutaecarpine in Evodia rutaecarpa was optimized. The mobile phase was [acetonitrile-tetrahydrofuran (25: 15)] -0.02% H3 PO4 (35:65). The detection wavelength was 220 nm and the flow rate was 1.0 mL x min(-1). Limonin, evodiamine and rutaecarpine were all well separated from other substances and their UV spectrums were essentially the same to the standards . The liner ranges of limonin, evodiamine and rutaecarpine were 0.196 8-3.936, 0.153 6-3.072, 0.097 4-1.948 microg. The average recoveries were 97.8%, 100.7% and 98.4%. RSD were 1.7%, 1.3% and 1.1% (n = 6). The method of this article is accurate, reproducible and can be used to enhance the quality control of E. rutaecarpa.

[Determination of evodiamine and rutacarpine in zhuyu hewei zhitong capsules by HPLC].

OBJECTIVE: To develop a HPLC method for the determination of evodiamine and rutacarpine in Zhuyu Hewei Zhitong capsules. METHOD: The separation was performed at 30 degrees C on an Eclipse XDB-C18 column (4.6 mm x 150 mm, 5 microm) eluted with the mobile phase consisted of acetonitrile-water(45:55). The detection wavelength was 250 nm. RESULTS: The standard curve for evodiamine is linear in the range of 0.0510-0.560 microg, the average recovery was 97.5% (RSD 1.0%). The standard curve for rutacarpine is linear in the range of 0.0508-0.559 microg, the average recovery was 98.7% (RSD 1.5%). CONCLUSION: The method is specific, accurate and stable. It can be used for detemination of evodiamine and rutacarpine in Zhuyu Hewei Zhitong capsules.

[Analysis on changes of chemical compounds in different processed products of Euodiae fructus].

OBJECTIVE: To study the relationship among processing methods and chemical compounds. METHOD: HPLC was used to compare the difference between pre and post processing. The main peaks in chromatogram were identified and divided into groups of chemical compounds. The contents of identified compounds and groups of chemical compounds were also analyzed. RESULT: The chromatographic peaks were divided into three groups of chemical compounds that were flavonoid glocosides, uinazoline alkaloids and bitter principle, indoloquinazoline alkaloids. The contents of flavonoid glocosides were reduced in each processed product, and that in hot-water processing product were the least. The contents of all three groups of chemical compounds were decreased in Coptidis Rhizoma processing products. The dissolving release of quinolones alkaloids were increased in wine, salt, Glycyrrhizae Radix et Rhizoma and ginger processing products. CONCLUSION: Different processing methods caused different changes of chemical compounds.

Bioanalysis of erlotinib, its O-demethylated metabolites OSI-413 and OSI-420, and other metabolites by liquid chromatography-tandem mass spectrometry with additional ion mobility identification.

Erlotinib is a first-generation epithelial growth factor receptor inhibitor used in the treatment of non-small cellular lung cancers. Our previously published method on a Thermo TSQ Quantum Ultra triple quadrupole mass spectrometer for the quantitation of erlotinib, OSI-420, and OSI-413 and some other kinase inhibitors was transferred to a more sensitive Sciex QTRAP5500 system. Both methods showed comparable performance in the previous range (5-5000 and 1-1000 ng/mL for erlotinib and OSI-420) with comparable accuracies and precisions (98.9-106.2 vs 98.7.0-104.0, and 3.7-13.4 vs 4.6-13.2), and a high level of agreement between the methods (R2 = 0.9984 and 0.9951) for the quality control samples. The new system however was also capable of quantifying lower concentrations of both erlotinib and OSI-420 (0.5 and 0.1 ng/mL) with sufficient accuracy and precision. Along with the increased sensitivity we included the semi-quantitative determination of additional erlotinib metabolites M2, M3, M5, M6, M7, M8, M9, M10, M11, M12, M16 (hydroxy-erlotinib), M17, M18, M19, M20, M21 in a 0.1-1000 ng/mL range to the method. With a simple crash, dilute, and shoot sample preparation with acetonitrile and a 4.5 min analytical run time the method outperformed most other published methods in speed and simplicity and was suitable for TDM. Further, enhancement of the understanding of the pharmacokinetics of erlotinib and its metabolites was demonstrated.

Ameliorative potential of Adhatoda vasica against anti-tubercular drugs induced hepatic impairments in female Wistar rats in relation to oxidative stress and xeno-metabolism.

ETHNOPHARMACOLOGICAL RELEVANCE: Adhatoda vasica Nees is widely used herb of indigenous system to treat various ailments especially upper respiratory tract infections. Not only, anti-tubercular efficacy of crude extract and phytoconstituents of A. vasica has been documented but its hepatoprotective role against various drugs mediated hepatic alterations in different animal models has also been observed. BACKGROUND AND PURPOSE: Isoniazid, rifampicin and pyrazinamide (H-R-Z) are anti-tubercular drugs normally prescribed by health professionals for the treatment of tuberculosis, however along with their medical effectiveness these drugs also exhibit hepatotoxicity among TB patients. Unexpectedly, substantial toxicological data on the metabolism of anti-TB drugs are available but the mystery behind these xenobiotics is too complex and partly implicit. In this study, we further explored the hepatotoxic effects of these xeno-metabolic products and their amelioration by Adhatoda vasica Nees by elucidating its mechanistic action. METHODS: We generated a hepatotoxic rodent model by oral administration of H, R and Z (30.85, 61.7 and 132.65 mg/kg body weight) drugs for 25 days in Wistar rats. Additionally, to achieve hepatoprotection two different doses of Adhatoda vasica Nees ethanolic leaf extract (200 and 300 mg/kg body weight) were used along with H-R-Z dosage, orally and once daily for 25 days and tried to ascertain their mechanistic action. For this, initially phytoconstituents of the extract were evaluated followed by extract standardization using RP-HPLC and FTIR methods. Furthermore, antioxidant activity of the extract was analyzed by DPPH assay. Finally, different treated groups were analyzed for hepatic oxidative stress markers, antioxidant markers, histopathological changes and gene expression study including CYP2E1, CYP7A1, NAT, NR1I2 and UGT1A1 genes involved in phase I and phase II xeno-metabolism. RESULTS: Estimated content of vasicine in RP-HPLC method and free-radical scavenging activity in DPPH assay was found to be 134.519 ± 0.00269µg/10mg of leaf extract and 47.81 µg/mL respectively. In H-R-Z treated group, a significant increase in the levels of thiobarbituric acid, significant reduction in the levels of GSH, and enzymatic markers and marked changes in hepatic histological architecture were observed. In addition, there was significance up-regulation of CYP7A and NAT genes, down-regulation of CYP2E1 gene and insignificant expression levels of NR1I2 and UGT1A1 genes were observed in H-R-Z group. Conversely, high dose of A. vasica extract effectively diminished these alterations by declining oxidative stress and boosting of antioxidant levels. In addition, it acted as bi-functional inducer of both phase I (CYP2E1) and phase II (NAT and UGT1A1) enzyme systems. CONCLUSION: Hence, we concluded that anti-TB drugs exposure has potential to generate reactive metabolites that eventually cause hepatotoxicity by altering oxidant-antioxidant levels and their own metabolism. This study not only emphasized on xeno-metabolism mediated hepatic alterations but also explore the benefit of A. vasica on these toxic insults.

HPLC fingerprints combined with principal component analysis, hierarchical cluster analysis and linear discriminant analysis for the classification and differentiation of Peganum sp. indigenous to China.

INTRODUCTION: Seeds of wild Peganum harmala Linn., P. multisectum (Maxim) Bobr., P. nigellastrum Bunge and a probable indeterminate species, herein referred to as P. variety, are commonly used in Chinese medicine. These seeds cannot be differentiated based on morphology. OBJECTIVE: Seeds of P. harmala Linn., P. multisectum (Maxim) Bobr., P. nigellastrum Bunge and P. variety were collected in different provinces in China and their HPLC profiles were recorded for statistical analysis and pattern recognition.Methodology - HPLC chromatograms of seed extracts were recorded under the same conditions. Individual HPLC chromatograms for each species were evaluated against the mean chromatogram for the same species generated using a similarity evaluation computer program. Data from chromatographic fingerprints were also processed using principal component analysis (PCA), hierarchical cluster analysis (HCA) and linear discriminant analysis (LDA). RESULTS: The Peganum sp. seed extracts had similar HPLC fingerprints but with some inter-specific differences. The chromatographic fingerprints combined with PCA, HCA and LDA could distinguish the seeds of the different species of Peganum investigated. CONCLUSION: HPLC fingerprints can be used to authenticate and differentiate the seeds of three different species of genus Peganum indigenous to China. The results indicated that the unidentified P. variety might indeed be a new species or variety.