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A hydrophilic interaction chromatography tandem mass spectrometry method was developed for simultaneous quantification of 35 components in gualoupi injection. The analytes were separated with an ACQUITY XBridge Amide column using 20 mmol·L-1 ammonium formate aqueous solution (pH 3.0) as mobile phase A and 20 mmol·L-1 ammonium formate (pH 3.0)∶acetonitrile (1∶9) as mobile phase B for gradient elution. Mass spectrometry with dynamic multiple reaction monitoring and external standard method were used for quantitative analysis. A total of 35 components were determined in 10 batches of gualoupi injection. The results showed that the 35 compounds had a good linear relationship within their respective concentration ranges with the correlation coefficients (R2 > 0.998 0), the recoveries ranged from 76.6% to 118.5%. The results showed that γ-aminobutyric acid, trigonelline, alanine, threonine, homoserine, citrulline, and leucine were abundant in gualoupi injection, while nicotinamide, methylsuccinic acid, cytosine and choline account for a low percentege. The present study provides an important reference for elucidation of the effective material basis and the improvement of quality standard of gualoupi injection.
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Background The production and consumption of high polar pesticides in China are the largest in the world. Therefore, it is urgent to develop a method with fast analysis, large flux, and high accuracy to determine the residues of these pesticides in food. Objective To establish a method for the determination of eight highly polar pesticides [chlormequat, paraquat, difenzoquat, cyromazine, propamocarb, glyphosate, (aminomethyl)-phosphonic acid, and glufosinate] in vegetables and fruits by ultra-performance liquid chromatography-tandem mass spectrometry. Methods After comparing various types of hydrophilic interaction liquid chromatography (HILIC) columns, and optimizing pH value and buffer concentration of mobile phase, effective chromatographic retention and separation of selected eight pesticides were achieved. Based on the optimization of mass spectrometry under chromatographic conditions, a multiple reaction monitoring (MRM) channel of target compounds was established. In the sample pretreatment, through optimization of water content, extraction solvent, and purification method, a final MRM mode of ultra-performance liquid chromatography-tandem mass spectrometry was used for detection, and the isotope internal standard method was used for quantification. The accuracy and the precision of the method were evaluated using recovery and relative standard deviation. The established method was applied to detect 57 samples of retail vegetables and fruits to investigate the adaptability of the proposed method and the residual levels of selected high polar pesticides. Results For positive ion electrospray ionization (ESI+) detection, we chose Sielc Obelisc R as chromatographic column, and 20 mmol·L−1 ammonium formate solution (pH=3±0.05) and acetonitrile as mobile phase; for negative ion electrospray ionization (ESI−) detection, we chose Shodex Asahipak NH2P-50 2D as chromatographic column, and 5 mmol·L−1 ammonium acetate solution (pH=11±0.05) and acetonitrile as mobile phase to obtain good chromatographic separation and peak shape. Under the optimal conditions of sample water content standardization, using 2% acidified methanol as extraction solvent, and C18 dispersed solid phase extraction purification, the linearity ranges of five analytes (chlormequat, paraquat, difenzoquat, cyromazine, and propamocarb) and three analytes [glyphosate, (aminomethyl)phosphonic acid, and glufosinate] were 1.00-100 μg·L−1 and 5.00-500 μg·L−1 (both correlation coefficients>0.999) respectively, the detection limits were 0.002-0.010 mg·kg−1, and the limits of quantification (LOQ) were 0.005-0.025 mg·kg−1. At three spiked levels (LOQ, 2LOQ, and 5LOQ), the recoveries were in the range of 85.3%–113.2%, and the relative standard deviations were 1.5%–9.5% (n=6). Three target pesticides (chlormequat, cyromazine, and propamocarb) were detected in 57 samples of retail vegetables and fruits, and the residue of chlormequat in cowpea exceeded the maximum residue limit. Conclusion The established method of HILIC combined with ultra-performance liquid chromatography-tandem mass spectrometry and isotopic internal standard quantification has the characteristics of simplicity, stability, and easy operation, which is suitable for rapid screening and quantitative detection of selected eight high polar pesticide residues in large quantities of vegetables and fruits, and provides technical support for monitoring and risk assessment of high polar pesticide residues.
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An analytical method was developed for determination of 7 aminoglycosides antibiotics in bear bile powder by hydrophilic interaction liquid chromatography tandem mass spectrometry. The samples were purified by mix-mode weak cation exchange and reversed-phase SPE. Waters ACQUITY UPLC BEH Amide column (100 mm × 3.0 mm, 1.7 μm) was used with 0.2% formic acid aqueous solution-0.2% formic acid acetonitrile solution as mobile phases by gradient elution. The aminoglycosides were detected by electrospray ionization mass spectrometry in positive mode with multiple reaction monitoring (MRM) mode. Spectinomycin, streptomycin, amikacin, kanamycin, tobramycin, apramycin and neomycin possessed good linear correlation in the respective concentration ranges, with the correlation coefficients more than 0.99. The mean recoveries at 3 spiked levels were in the range of 61.3%～127.3%, and the RSDs were 0.1%～1.9%. The limits of quantification were 0.2～1.0 mg·kg-1. The method had been applied to the analysis of actual samples.
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OBJECTIVE: To validate the HILIC-UPLC method for N-glycan profile analysis of therapeutic antibodies. METHODS: The interlaboratory method validation was performed according to ICH_Q2_R1 guideline and general principles of China Pharmacopoeia (2015 edition) 9101. The validation items included specificity, linearity, accuracy, precision, quantitation limit, range and robustness. RESULTS: The method showed good specificity, accuracy, precision and robustness, and showed a good linearity at a protein range from 100 to 400 μg. The r2 of linear regression equation was above 0.98, and the recoveries were between 86% and 117%. Both the RSDs of peak area percentage and retention time were below 10%, which indicated good precision. The lower quantitation limit of the method was 0.040%, and the range was from 0.040% to 78.751%, which means that single peak at this range could be quantified accurately. Furthermore, robustness evaluation under a series of conditions showed that this method was robust, where the RSD of peak area percentage was below 5% and RSD of retention time was below 1%. CONCLUSION: Interlaboratory validation of HILIC-UPLC provides a methodological verification basis for the improvement of Chinese Pharmacopoeia standards.
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Chemical profiling of a given herbal medicine( HM) is the prerequisite for clarifying the effective material basis and therapeutic mechanisms,and it is an important integral part of traditional Chinese medicine chemical biology( TCMCB). In current study,we aimed to propose a new strategy for fast chemical characterization of HM by using reversed phase liquid chromatography-hydrophilic interaction chromatography-predictive multiple reaction monitoring( RPLC-HILIC-p MRM),and Artemisiae Scopariae Herba was employed in this study to illustrate the entire strategy. In response to wide polarity spanning of the diverse chemical clusters in Artemisiae Scopariae Herba,RPLC and HILIC were coupled in series to retain and separate hydrophilic and hydrophobic components simultaneously by identifying the characteristics of chromatographic separation. Most of the chemical constituents in traditional Chinese medicine can be predicted by summarizing the results of chemical constituents of the same genera and introducing primary metabolites and possible substitution reaction types. Therefore,we constructed predictive ion pairs to rapidly identify the chemical constituents of Artemisiae Scopariae Herba. After comparison with control products,discussion on fragmentation pattern,and access to relevant information from literature and databases,a total of 139 components were detected and structurally annotated by matching the obtained spectral data with the information of authentic compounds. Above all,RPLC-HILIC-p MRM could be used as an eligible analytical tool for the chemical profiling of HMs.
Subject(s)
Artemisia , Chemistry , Chromatography, Reverse-Phase , Hydrophobic and Hydrophilic Interactions , Medicine, Chinese Traditional , Plants, Medicinal , ChemistryABSTRACT
This study was aimed to identify the photodegradation impurities (PD1 and PD2) in melphalan hydrochloride and establish a method for determining PD1 and PD2.The structures of the photodegradation impurities were inferred by LC-MS/MS.The impurities were confirmed by comparing with synthesized impurities.An HILIC method was established to determine PD1 and PD2.The method was carried out on an Atlantis HILIC column(4.6 mm × 150 mm,3 μm) with the mobile phase consisting of 0.1 mol/L ammonium formate (adjusted to pH 3.0 with formic acid) and acetonitrile (13∶ 87) at the flow rate of 1.0 mL/min.The column temperature was 35 ℃.The detection wavelength was 260 nm.PD1 and PD2 were characterized as 4-amino-L-phenylalanine hydrochloride and 4-(2-chloroethyl) amino-L-phenylalanine hydrochloride,respectively.Melphalan hydrochloride,PD1 and PD2 were separated completely under the HILIC condition.The established HILIC method can be used to determine the photodegradation impurities.
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Bladder cancer ( BC) is a fatal malignancy with considerable mortality, and can cause a serious threat to human health. The successful treatment of bladder cancer relies mainly on early detection. Biomarkers are vital to early diagnosis of bladder cancer, and metabonomics play an important role in biomarkers finding. In this study, we used 69 polar metabolites to select the appropriate separation system and develop the zwitterionic hydrophilic chromatography/mass spectrometry ( ZIC-HILIC/MS ) method. In this method, 50 representative compounds had broad linear ranges between 2-6 orders of magnitude. Moreover the limit of detection of the method was below ng/mL levels. The analysis for six serum samples prepared in parallel showed that this method had good reproducibility, and the RSDs of more than 85% metabolites were less than 30%. Based on this method, it was found that 35 metabolites had significant differences in BC group and healthy control. After screening and validation, the combination of chenodeoxycholic acid, eicosenoic acid, GPC, dodecenoic acid and cystine was a potential biomarker to distinguish BC and normal group. These results indicated that the ZIC-HILIC/MS method could detect diverse metabolites for metabolomic analysis purpose with good reproducibility and stability.
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Abstract A method based on dispersive solid phase extraction-high performance liquid chromatography-tandem mass spectrometry for determination of 19 kinds of nonprotein nitrogen compounds including melamine, cyromazine, amidinourea, aminotriazine, 3-aminotriazole, 4-aminotriazole, allantoin, cyanuric acid, dicyandiamide, thiourea, semicarbazide, L-leucine, L-isoleucine, L-arginine, L-hydroxyproline, L-theanine, ammeline, ammelide and guanidine in powdered formulas was presented. The nonprotein nitrogen compounds were degreased by chloroform and extracted by acetonitrile, with MgSO4 to remove water and C18 to clean up. The samples were separated on Merck ZIC HILIC column (150 mm í2. 1 mm, 5 μm, 20 nm) with gradient elution. The electrospray ionization was operated in the positive mode and negative mode, and monitored by the multiple reaction monitoring ( MRM) mode. Allation was quantified by external standard method and the other 18 kinds of nonprotein nitrogen compounds were quantified by internal standard method. All of the correlation coefficients (r) were higher than 0. 99. The limits of quantitation (LOQ) were 0. 05-5. 0 mg/kg, the average recoveries were between 82 . 2% and 115 . 0%, and the relative standard deviations were less than 20%.
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Anultra-performancehydrophilicinteractionliquidchromatography-triplequadrupolemass spectrometric ( UPLC-MS/MS) method was developed for the determination of tetrodotoxin ( TTX) in human urine and plasma. After the sample was cleaned-up and concentrated by immunoaffinity column, the separation of the TTX was carried out on an Acquity UPLC BEH amide column (100 mm×2. 1 mm, 1. 7 μm) with gradient elution using mobile phases of 0. 1% ( V/V) formic acid in water and acetonitrile. The analyte was detected by positive electrospray ionization mass spectrometry in the multiple reaction monitoring ( MRM) mode, and quantified by external solvent standard calibration. The measuring ranges of TTX in urine and plasma were 0. 05-400 μg/L. The average recoveries were 92%-95% and 91%-96% for TTX respectively spiked in urine and plasma with relative standard deviations of 3 . 3%-7 . 2% and 3 . 9%-7 . 8% ( n=5 ) . The limits of detection (LOD, S/N=3) and limits of quantitation (LOQ, S/N=10) of TTX were 0. 02 μg/L and 0. 05μg/L for urine and plasma, respectively. This method is suitable for the detection of TTX in urine and plasma for both forensic and clinical purposes.
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A rapid method for the detection of tetrodotoxin(TTX) in human plasma and urine was developed by hydrophilic interaction liquid chromatography-tandem mass spectrometry. After a simple protein precipitation step was undertaken, the subsequent analysis of TTX was achieved on a TSK-gel amide-80 column using an ammonium formate-methanol-acetonitrile gradient with a cycle time of 13 min, and detected by positive electrospray ionization tandem mass spectrometry in the MRM mode, and quantified by matrix-match standard solution. It was found that linearity in urine was observed within concentration ranged from 3 μg/L to 500 μg/L, that in plasma 1 μg/L to 200 μg/L and that limits of detection(S/N=3) for urine and plasma were 1 and 0.3 μg/L, respectively. The average recoveries were 96%-108% and 100%-105% for TTX spiked in urine and plasma, respectively, with relative standard deviations of 1.7%-8.6% and 8.9%-16%(n=6). This method was simple, selective and sensitive to detect TTX in urine and plasma for both clinical and forensic purposes.