Objectives: To study the characteristics of serum metabonomics in coronary heart disease (CHD) patients diagnosed as phlegm or blood stasis pattern and explore effects of formula-pattern correspondence treatment. M...Objectives: To study the characteristics of serum metabonomics in coronary heart disease (CHD) patients diagnosed as phlegm or blood stasis pattern and explore effects of formula-pattern correspondence treatment. Methods: A total of 102 stable CHD patients were enrolled and divided into phlegm group (P group, n=52) and blood stasis group (BS group, n=50) according to pattern identification. Gualou Xiebai Banxia Decoction (瓜萎薤白半夏汤, GXBD) and Xuefu Zhuyu Decoction (血府逐瘀汤, XZD) were used as drug interventions. Relevant indicators of metabonomics were observed by ultra performance liquid chromatography mass spectrometry (UPLC-MS) and pattern recognition. Results: Levels of amino acids and phosphatidylethanolamine (PE) in the CHD group were much higher than those in healthy control group, while the levels of unsaturated fatty acids, sphingosine, Lyso, phosphatidylcholine (PC) were significantly lower (P〈0.01). Most of the differential metabolites between the CHD and the healthy groups were also common metabolites of phlegm and blood stasis. 7(Z), 10(Z)- hexadecadienoic acid and DPA were decreased in the P group and increased in the BS group. According to the quantity of retraced metabolites, improvement in metabonomics by formula-pattern correspondence was superior to that without correspondence in the BS group. Based on the varieties of metabolites, GXBD could improve the levels of docosapentaenoic acid (DPA), sphingomyelin (SM) (d34:1), and L-Lactic acid and XZD could ameliorate the levels of sphingosine and Vit E in the P group, in the BS group, GXBD could improve vitamin E level and XZD could make improvements in the levels of octadecanoic acid, phosphoglycerol, and SM (d34:1). Conclusions: Phlegm and blood stasis in CHD patients present specific differential metabolites, and share common metabolites. Remarkable differences have been displayed in pathological properties and severity of phlegm and blood stasis. Patients with phlegm are more likely to have lipid metabolism disorders. However, in patients with blood stasis, problems mainly lie in glucose, protein and fat metabolism and the injury of vascular cell membrane is relatively severe. The metabolic disorder is more complicated in blood stasis pattem than that in phlegm pattem. Compared with non-correspondence, improvement of differential metabolites is more comprehensive and targeted in formulapattern correspondence with a better effect.展开更多
Mitochondria regulate numerous crucial cell processes, including energy production, apoptotic cell death, oxidative stress, calcium homeostasis and lipid metabolism. Here, we applied an efficient mitochondria-based ce...Mitochondria regulate numerous crucial cell processes, including energy production, apoptotic cell death, oxidative stress, calcium homeostasis and lipid metabolism. Here, we applied an efficient mitochondria-based centrifugal ultrafiltration/liquid chromatography/mass spectrometry(LC/MS) method,also known as screening method for mitochondria-targeted bioactive constituents(SM-MBC). This method allowed searching natural mitochondria-targeting compounds from traditional Chinese medicines(TCMs), including Puerariae Radix(PR) and Chuanxiong Radix(CR). A total of 23 active compounds were successfully discovered from the two TCMs extracts. Among these 23 hit compounds, 17 were identified by LC/MS, 12 of which were novel mitochondria-targeting compounds. Among these, 6 active compounds were analyzed in vitro for pharmacological tests and found able to affect mitochondrial functions. We also investigated the effects of the hit compounds on Hep G2 cell proliferation and on loss of cardiomyocyte viability induced by hypoxia/reoxygenation injury. The results obtained are useful for in-depth understanding of mechanisms underlying TCMs therapeutic effects at mitochondria level and for developing novel potential drugs using TCMs as lead compounds. Finally, we showed that SM-MBC was an efficient protocol for the rapid screening of mitochondria-targeting constituents from complex samples such as PR and CR extracts.展开更多
Objective High performance liquid chromatography(HPLC)and liquid chromatography-mass spectrometry(LC/MS)methods were developed for the determination of ganciclovir and its related substances.Methods A Hypersil ODS2 co...Objective High performance liquid chromatography(HPLC)and liquid chromatography-mass spectrometry(LC/MS)methods were developed for the determination of ganciclovir and its related substances.Methods A Hypersil ODS2 column(4.6 mm×250 mm,5 μm)was used with a mobile phase of 0.02 M potassium dihydrogen phosphate buffer(pH 6.0)-methanol(92∶8)at a flow rate of 1.0 mL/min,and UV detector set at 254 nm was used for monitoring the eluents.Results The method was simple,rapid,selective and capable of separating all related substances at trace level with a detection limit of 0.04 μg/mL.It has been validated with respect to accuracy,precision,linearity,and limits of detection and quantification.The linearity range was 10.2-153.0 μg/mL with r=0.9998.The percentage recoveries ranged from 96.7% to 101.6%,and RSD was 1.24%-1.96%(n=5).Conclusion The method was found to be suitable not only for monitoring the reactions during the process development but also for quality control of ganciclovir.For identification of related substances,LC/MS was used.The mainly related substances of ganciclovir active pharmaceutical ingredients(API)were determined as guanine,(1,3-dioxolan-4-yl)methyl acetate,and diacetyl guanine.展开更多
Eighteen sex hormones in antler velvet were determined by high performance liquid chromatography tandem mass spectrometry.The solid phase extraction was applied to eliminating the matrix effect.The experimental condit...Eighteen sex hormones in antler velvet were determined by high performance liquid chromatography tandem mass spectrometry.The solid phase extraction was applied to eliminating the matrix effect.The experimental conditions were examined and optimized.Under the optimal conditions,the proposed method provides the good linearities and determination limits(0.2―1.0 μg/kg) of the analytes investigated.The recoveries ranging from 72.3% to 149.5% were obtained for the target analytes at two concentration levels.This method was applied to the determination of eighteen sex hormones in different kinds of antler velvet samples and the obtained results are satisfactory.The results indicate that the proposed method is suitable for the determination of sex hormones in antler velvet samples.展开更多
A reliable,selective and sensitive liquid chromatography tandem mass spectrometry method was developed and validated for the quantification of lamotrigine in human plasma using lamotrigine13C3,d3 as an internal standa...A reliable,selective and sensitive liquid chromatography tandem mass spectrometry method was developed and validated for the quantification of lamotrigine in human plasma using lamotrigine13C3,d3 as an internal standard.Analyte and internal standard were extracted from human plasma by solid-phase extraction and detected in positive ion mode by tandem mass spectrometry with electrospray ionization(ESI) interface.Chromatographic separation was performed on a Chromolith s SpeedROD;RP-18e column(50-4.6 mm i.d.) using acetonitrile:570.1 mM ammonium formate solution(90:10,v/v) as the mobile phase at a flow rate of 0.500 mL/min.The calibration curves were linear over the range of 5.02-1226.47 ng/mL with the lower limit of quantitation validated at 5.02 ng/mL.The analytes were found stable in human plasma through three freeze(-20℃)-thaw(ice-cold water bath) cycles and under storage on bench-top in ice-cold water bath for at least 6.8 h,and also in the mobile phase at 10℃ for at least 57h.The method has shown good reproducibility,as the intra-and inter-day precisions were within 3.0%,while the accuracies were within 76.0% of nominal values.The validated LC-MS/MS method was applied for the evaluation of pharmacokinetic and bioequivalence parameters of lamotrigine after an oral administration of 50mg lamotrigine tablet to thirty-two healthy adult male volunteers.展开更多
Taraxacum kok-saghyz(TKS)is rich in natural rubber(NR),a natural organic macromolecular compound composed of cis-1,4-polyisoprene,and may become the second NR-bearing plant for biochemical engineering development.In t...Taraxacum kok-saghyz(TKS)is rich in natural rubber(NR),a natural organic macromolecular compound composed of cis-1,4-polyisoprene,and may become the second NR-bearing plant for biochemical engineering development.In this paper,a rapid and quantitative ultra-high performance liquid chromatography tandem mass spectrometry(UHPLCMS/MS)method was established for determination of macromolecular biosynthesis substrate(dimethylallyl pyrophosphate,DMAPP)and initiator(farnesyl pyrophosphate,FPP)contained in TKS.A Kromasil C18 chromatographic column was used for separation,and the multi-reaction monitoring mode(MRM)of triple quadrupole mass spectrometry was used for detection.Quantification was performed by external calibration method.The results showed that the limit of detection(LOD)and the limit of quantitation(LOQ)of DMAPP were 2.42μg/L and 7.26μg/L,respectively,and the LOQ and the LOD of FPP were 1.02μg/L and 3.05μg/L,respectively.At a concentration of 1—1000μg/L,both analytes had good determination coefficients(>0.999)of calibration curve.The recoveries of DMAPP and FPP were between 99.0%and 117.1%.In real samples detection,the contents of DMAPP and FPP in TKS samples were between 23.32—82.77μg/L and 12.03—85.67μg/L,respectively.Thus,this approach is a reliable method to quantify DMAPP and FPP in TKS.展开更多
[Objectives]A rapid screening and analysis method for 26 organophosphorus agrochemicals in fresh milk was established using ultra performance liquid chromatography coupled with quadrupole-time of flight mass spectrome...[Objectives]A rapid screening and analysis method for 26 organophosphorus agrochemicals in fresh milk was established using ultra performance liquid chromatography coupled with quadrupole-time of flight mass spectrometry.[Methods]Raw milk was extracted with acetonitrile solution containing 0.2%formic acid by volume,and purified with a Dikma ProElut QuECHERS solid phase extraction cartridge.Target compounds were separated on a Waters ACQUITY UPLC HSS T3 chromatographic column(2.1 mm×50 mm,1.8μm)with methanol-water solution as a mobile phase for gradient elution,and through scanning with an electrospray ion source in positive ion mode,26 kinds of organophosphorus agrochemicals could be accurately qualitatively determined within 10 min.[Results]When using formic acid acetonitrile with a volume fraction of 0.2%,there were more types of detected compounds and a greater recovery;and using B cartridge could effectively eliminate the interference of non-polar substances such as phospholipids,achieve higher number of detected compounds than those of A and C,and well separate the 26 kinds of agrochemical residues.[Conclusions]This study provides a reference method for the rapid screening of agrochemical residues in dairy cows in the future.展开更多
Centrifugal ultrafiltration after methanol extraction of whole plasma was used as an optimal condition for the preparation of blood plasma before metabonomic studies. The plasma samples from 102 lung cancer patients a...Centrifugal ultrafiltration after methanol extraction of whole plasma was used as an optimal condition for the preparation of blood plasma before metabonomic studies. The plasma samples from 102 lung cancer patients and 34 healthy volunteers were prepared with this approach. With ultra-performance liquid chromatography(UPLC) coupled with quadrupole time-of-flight mass spectrometry(Q-TOF MS) analysis, the samples were investigated in order to find potential disease biomarkers. After data acquisition, orthogonal signal correction partial least squares models were built to differentiate the healthy volunteers from lung cancer patients and to identify metabolites that showed significantly different expression between the two groups. Several metabolite ions were identified as potential biomarkers according to the variable importance in the project(VIP) value in both ion modes. Five lysophosphatidylcholines were further identified as specifically lysoPC 16:0, isomer of lysoPC 16:0, lysoPC 18:0, lysoPC 18:1 and lysoPC 18:2. These results suggest that UPLC coupled with Q-TOF MS is an effective technique for the analysis of plasma metabolites in metabonomic studies.展开更多
In order to identify the potential nephrotoxic compounds in traditional Chinese medicine Lithospermum erythrorhizon,it was separated into serial fractions according to their polarities.An in vitro method was utilized ...In order to identify the potential nephrotoxic compounds in traditional Chinese medicine Lithospermum erythrorhizon,it was separated into serial fractions according to their polarities.An in vitro method was utilized to determine the nephrotoxicity of these fractions with the help of fluorescence image analysis.As a result,the primary fraction A05 and its secondary fractions C06 "C09 and C12 "C14 were found to have significant toxicity to LLC-PK1 cell line,as determined by the survive rate less than 20% after they were treated with these fractions.These potential nephrotoxic fractions were further analyzed by multistage and high resolution mass spectrometry.The main compounds in these fractions were tentatively identified to be acetylshikonin,isobutyrylshikonin,β,β'-dimethyla-cryloylshikonin,and isovalerylshikonin,which may bring nephrotoxicity.展开更多
The standards of plant toxins were separated by a C18 column with gradient elution with 0.1% formic acid/water (V/V) and 0.1% formic acid/acetonitrile (V/V) as mobile phase and acquired by ion mobility-quadrupole time...The standards of plant toxins were separated by a C18 column with gradient elution with 0.1% formic acid/water (V/V) and 0.1% formic acid/acetonitrile (V/V) as mobile phase and acquired by ion mobility-quadrupole time of flight mass spectrometry (IM-QTOF MS) in positive ion mode. A database of 308 plant toxins including retention time, collision cross-section (CCS) and its fragment ions was established. Honey dissolved in water or herbal beverage was extracted by acetonitrile and purified with PSA sorbent, and then acquired by ultrahigh-performance liquid chromatography IM-QTOFMS. The acquired data were processed by comparing with the database we established to confirm the target compounds. The average recoveries for samples at two levels ranged from 60.6% - 120.1%, with relative standard deviation (n = 6) less than 25%. The limit of quantitation for plant toxins ranged from 1 - 20 μg/kg. The developed screening method was used in determination of honey, herbal beverage and honey flavored tea beverage samples. The results showed that berberine was detected in one honey with 1 μg/kg and caffeine was present in some beverages with the concentration from 200 and 5500 μg/kg. This method could meet the requirement for rapid screening of plant toxins in honey and herbal beverage. It can be used for the quality control of honey and herbal beverage in enterprises or quality inspection departments. It also can be used in the rapid screening of food poisoning.展开更多
Microglia,the primary immune cells within the brain,have gained recognition as a promising therapeutic target for managing neurodegenerative diseases within the central nervous system,including Parkinson’s disease.Na...Microglia,the primary immune cells within the brain,have gained recognition as a promising therapeutic target for managing neurodegenerative diseases within the central nervous system,including Parkinson’s disease.Nanoscale perfluorocarbon droplets have been reported to not only possess a high oxygen-carrying capacity,but also exhibit remarkable anti-inflammatory properties.However,the role of perfluoropentane in microglia-mediated central inflammatory reactions remains poorly understood.In this study,we developed perfluoropentane-based oxygen-loaded nanodroplets(PFP-OLNDs)and found that pretreatment with these droplets suppressed the lipopolysaccharide-induced activation of M1-type microglia in vitro and in vivo,and suppressed microglial activation in a mouse model of Parkinson’s disease.Microglial suppression led to a reduction in the inflammatory response,oxidative stress,and cell migration capacity in vitro.Consequently,the neurotoxic effects were mitigated,which alleviated neuronal degeneration.Additionally,ultrahigh-performance liquid chromatography–tandem mass spectrometry showed that the anti-inflammatory effects of PFP-OLNDs mainly resulted from the modulation of microglial metabolic reprogramming.We further showed that PFP-OLNDs regulated microglial metabolic reprogramming through the AKT-mTOR-HIF-1αpathway.Collectively,our findings suggest that the novel PFP-OLNDs constructed in this study alleviate microglia-mediated central inflammatory reactions through metabolic reprogramming.展开更多
Keto-enol tautomers of curcumin were confirmed by reversed-phase liquid chromatography(RPLC)/ hybrid quadrupole ion trap/time-of-flight mass spectrometry(QIT/TOFMS).Tautomers gave different MS/MS spectra in negati...Keto-enol tautomers of curcumin were confirmed by reversed-phase liquid chromatography(RPLC)/ hybrid quadrupole ion trap/time-of-flight mass spectrometry(QIT/TOFMS).Tautomers gave different MS/MS spectra in negative mode.Different mass spectra were also obtained by hydrogen/deuterium exchange LC/MS/MS in positive mode.Our results suggest that enol form is the major form in the solution(water/acetonitrile).展开更多
Comprehensive two-dimensional liquid chromatography platform(LC×LC)coupled with quadrupole time-of-flight(QTOF)mass spectrometry(MS)is developed to separate,identify and relatively determine the chemical constitu...Comprehensive two-dimensional liquid chromatography platform(LC×LC)coupled with quadrupole time-of-flight(QTOF)mass spectrometry(MS)is developed to separate,identify and relatively determine the chemical constituents of two types of tripterygium glycosides tablets(TGT).The types and relative contents of the constituents discovered in two kinds of TGT tablets were subsequently compared.C8andC18 column were used for the separation of the first展开更多
In this paper, a high-performance liquid chromatography coupled with ultraviolet detection and Fourier transform-ion cyclotron resonance mass spectrometry (HPLC-UV/FrICRMS) method was described for the investigation...In this paper, a high-performance liquid chromatography coupled with ultraviolet detection and Fourier transform-ion cyclotron resonance mass spectrometry (HPLC-UV/FrICRMS) method was described for the investigation of impurity profile in moxifloxacin (MOX) drug substance and chemical reference substance. Ten impurities were detected by HPLC-UV, while eight impurities were identified by using the high accurate molecular mass combined with multiple-stage mass spectrometric data and fragmentation rules. In addition, to our knowledge, five impurities were founded for the first time in MOX drug substance.展开更多
Objective: To compare the pharmacokinetic differences of the main components of Naoxintong capsule(NXTC) in normal and acute blood stasis rats. Materials and Methods: Rats were subcutaneously injected with adrenaline ...Objective: To compare the pharmacokinetic differences of the main components of Naoxintong capsule(NXTC) in normal and acute blood stasis rats. Materials and Methods: Rats were subcutaneously injected with adrenaline hydrochloride twice;during the two subcutaneous injections, the rats were placed in ice water for 4 min to reproduce the model rat of acute blood stasis. The normal and acute blood stasis rats were administrated a 5.04 g/kg dose of NXTC suspension. Then, blood samples were collected from the posterior retinal venous plexus at different time points. Plasma concentrations of four major bio-active components including caffeic acid, ferulic acid, formononetin, and tanshinone IIA in NXTC were measured using ultra-performance liquid chromatography coupled with triple-quadrupole mass spectrometry. Phoenix Win Nonlin v6.2 software was used to calculate the pharmacokinetic parameters. Results: Compared with the normal rats, the acute blood stasis rats showed a significant decrease in C_(max) of ferulic acid and formononetin, AUC_(all) of caffeic acid and ferulic acid, and AUC_(INF_obs) of ferulic acid. Conversely, an increase in the Vz_F_obs and MRT_(last) of ferulic acid and caffeic acid was observed. These findings demonstrate that the absorption of the four NXTC components was weakened in the acute blood stasis rats and that the elimination time was prolonged. Conclusions: The significant difference in some parameters of the four NXTC components between the normal and acute blood stasis rats might be caused by an increase in blood viscosity and the subsequent slowing down of blood flow in the acute blood stasis rats. The pharmacokinetic study conducted in pathological state can provide important information and scientific basis for further rational clinical application of NXTC.展开更多
Objective:There are different geographic origins of Aconiti Kusnezoffii Radixs(AKRs)sold in the market with different quality.This study aims to establish a rapid analysis method to distinguish the different geographi...Objective:There are different geographic origins of Aconiti Kusnezoffii Radixs(AKRs)sold in the market with different quality.This study aims to establish a rapid analysis method to distinguish the different geographic origins of AKRs and to realize the rapid evaluation of their quality.Methods:An ultra-performance liquid chromatography coupled with time-of-flight mass spectrometry(UPLC-Q-TOF MS)method was utilized to acquire the constituents'information of AKRs from different geographic origins.MSE data and Progenesis QI software were employed to identify the chemical constitutes.Principal component analysis(PCA)was applied to comparing MS data to find the chemical markers of AKRs from different geographic origins.Results:Twenty-three components were detected and 17 out of them were identified,including diester-diterpenoid alkaloids,monoester-diterpenoid alkaloids,and amine-diterpenoid alkaloids.Three pairs of isomers were detected and two of them were distinguished by the retention time of standard samples.Thirteen chemical markers were screened out through PCA and orthogonal partial least square discriminant analysis.Through detecting Napelline or isomer of Napelline(m/z 360.2530)and Aconifine(m/z 662.3170),AKRs from inner Mongolia autonomous could be screened.According to the existence of benzoylaconine(m/z 604.3108)and Indaconitine(m/z 630.3159),it could be confirmed that the AKRs are from Xinjiang Uygur autonomous.AKRs that cannot detect compounds above-mentioned could be from Liaoning or Shanxi Province.Conclusions:The chemical profile could be used not only to distinguish the AKRs from different geographic origins but also to identify the true and false of AKRs.This study lays a foundation for the study of efficacy and toxic of AKRs.展开更多
A rapid and high selective ultra-performance liquid chromatography(UPLC)with tandem mass spectrometry method for simultaneous determination of six compounds including albiflorin,paeoniflorin,picroside I,picroside II,s...A rapid and high selective ultra-performance liquid chromatography(UPLC)with tandem mass spectrometry method for simultaneous determination of six compounds including albiflorin,paeoniflorin,picroside I,picroside II,saikosaponin A,and saikosaponin D in rat plasma was developed and validated using butyl p-hydroxybenzoate as an internal standard.One-step direct protein precipitation with acetonitrile was used to extract the compounds from the rat plasma samples.Chromatographic separation was achieved using an ACQUITY UPLC BEH C18 column(100 mm×2.1 mm,1.7μm)at a flow rate of 0.4 m L/min,using gradient mode containing 0.1%formic acid in water and acetonitrile were used as the Mobile phase A and B.Electrospray ionization in negative ion mode and multiple reaction monitoring were used to identify and quantify active components.Calibration curves showed good linearity(R^2>0.9908)over a wide concentration range for all compounds.The intra-and interday precision(relative standard deviation)ranged 2.4%–7.0%and 2.6%–8.0%,respectively.The accuracy(relative error)was from-13.0%to 13.2%at all quality control levels.The recovery ranged from 81.1%to 92.5%.The validated method was successfully applied to pharmacokinetic study in rats after oral administration of Qing Gan-Shu Yu-Fang.The results show that one can draw a conclusion that these six active ingredients can be quickly absorbed and play a pharmacodynamic role rapidly in vivo.展开更多
A rapid and sensitive liquid chromatography tandem mass spectrometry(LC-MS/MS) method has been developed and validated for the determination of moxifloxacin(MOXI) in human plasma. After a simple protein precipitation ...A rapid and sensitive liquid chromatography tandem mass spectrometry(LC-MS/MS) method has been developed and validated for the determination of moxifloxacin(MOXI) in human plasma. After a simple protein precipitation using acetonitrile, the post treatment samples were analysed on a C18 column interfaced with a Triple Quadropole Tandem Mass Spectrometer. Positive electrospray ionization was employed as the ionization source. The mobile phase consisted of 0.1% formic acid–acetonitrile(60:40, v/v). Ciprofloxacin(CIPRO) was used as an internal standard. The analyte and internal standard(CIPRO) were monitored in the multiple reaction monitoring mode(MRM). The mass transition ion-pair has been followed as m/z 402→358.2 for MOXI and 332→288.1 for CIPRO. The method was linear in the concentration range of 25–5000 ng/mL. The lower limit of quantification was 25 ng/mL. The intra- and inter-day precision(relative standard deviation) and accuracy(relative error) values were within 12.4%. Each plasma sample was analyzed within 3 min.展开更多
Aspartame is a widely used sweetener, the long-term safety of which has been controversial ever since it was accepted for human consumption. It is unstable and can produce some harmful degradation products under certa...Aspartame is a widely used sweetener, the long-term safety of which has been controversial ever since it was accepted for human consumption. It is unstable and can produce some harmful degradation products under certain storage conditions. A high-performance liquid chromatography/tandem mass spectrometry method was developed for the simultaneous analysis of aspartame and its four degradation products, including aspartic acid, phenylalanine, aspartyl-phenylalanine and 5-benzyl-3,6- dioxo-2-piperazieacetic acid in water and in diet soft drinks. Aspartame and its four degradation products were quantified by a matrix matched external standard calibration curve with excellent correlation coefficients. The limits of detection were 0.16-5.8 μg/L, which exhibited higher sensitivity than common methods. This method was rapid, sensitive, specific and capable of eliminating matrix interferences. It was also applied to the study of the degradation of aspartame at various pH and temperatures. The results indicated that aspartame was partly degraded under strong acidic or basic conditions and the extent of degradation increased with increasing temperature.展开更多
A simple,rapid and sensitive liquid chromatography with tandem mass spectrometry method for the determination of periplocymarin in human blood and urine was developed.The digoxin‑d3 was used as an internal standard.Pe...A simple,rapid and sensitive liquid chromatography with tandem mass spectrometry method for the determination of periplocymarin in human blood and urine was developed.The digoxin‑d3 was used as an internal standard.Periplocymarin and digoxin‑d3(IS)were processed with ethyl acetate by liquid–liquid extraction.The chromatographic separation was performed on a Shim‑pack XR‑ODSIII C18 column with a 7 min gradient elution using methanol‑ammonium formate(5 mmol/L)as mobile phase at a flow rate of 0.3 mL/min(65:35,v/v).The detection was performed on a triple quadrupole tandem mass spectrometer using positive‑ion mode electrospray ionization in selected reaction monitoring mode.The periplocymarin was well separated from the internal standard.Two calibration curves were linear within the concentration range 0.01–1µg/mL.The limit of detection and quantification of blood and urine samples were both estimated at 0.005 and 0.01µg/mL.The interday and intraday precisions,accuracy,and recovery were assessed to verify this method.The results showed that the method was suitable for the determination of periplocymarin in forensic toxicological analysis and clinical diagnosis.展开更多
基金Supported by the National Natural Science Foundation of China(No.30901891)
文摘Objectives: To study the characteristics of serum metabonomics in coronary heart disease (CHD) patients diagnosed as phlegm or blood stasis pattern and explore effects of formula-pattern correspondence treatment. Methods: A total of 102 stable CHD patients were enrolled and divided into phlegm group (P group, n=52) and blood stasis group (BS group, n=50) according to pattern identification. Gualou Xiebai Banxia Decoction (瓜萎薤白半夏汤, GXBD) and Xuefu Zhuyu Decoction (血府逐瘀汤, XZD) were used as drug interventions. Relevant indicators of metabonomics were observed by ultra performance liquid chromatography mass spectrometry (UPLC-MS) and pattern recognition. Results: Levels of amino acids and phosphatidylethanolamine (PE) in the CHD group were much higher than those in healthy control group, while the levels of unsaturated fatty acids, sphingosine, Lyso, phosphatidylcholine (PC) were significantly lower (P〈0.01). Most of the differential metabolites between the CHD and the healthy groups were also common metabolites of phlegm and blood stasis. 7(Z), 10(Z)- hexadecadienoic acid and DPA were decreased in the P group and increased in the BS group. According to the quantity of retraced metabolites, improvement in metabonomics by formula-pattern correspondence was superior to that without correspondence in the BS group. Based on the varieties of metabolites, GXBD could improve the levels of docosapentaenoic acid (DPA), sphingomyelin (SM) (d34:1), and L-Lactic acid and XZD could ameliorate the levels of sphingosine and Vit E in the P group, in the BS group, GXBD could improve vitamin E level and XZD could make improvements in the levels of octadecanoic acid, phosphoglycerol, and SM (d34:1). Conclusions: Phlegm and blood stasis in CHD patients present specific differential metabolites, and share common metabolites. Remarkable differences have been displayed in pathological properties and severity of phlegm and blood stasis. Patients with phlegm are more likely to have lipid metabolism disorders. However, in patients with blood stasis, problems mainly lie in glucose, protein and fat metabolism and the injury of vascular cell membrane is relatively severe. The metabolic disorder is more complicated in blood stasis pattem than that in phlegm pattem. Compared with non-correspondence, improvement of differential metabolites is more comprehensive and targeted in formulapattern correspondence with a better effect.
基金Financial support from the National Natural Science Foundation of China (Grant 81660596, 81673395 and 81373921)the Research Fund for the Doctoral Program of Higher Education of China (Grant 20130001110057)the Application and Basis Research Project of Yunnan China (Grant 2017FF117-(013) and 2016FD050)
文摘Mitochondria regulate numerous crucial cell processes, including energy production, apoptotic cell death, oxidative stress, calcium homeostasis and lipid metabolism. Here, we applied an efficient mitochondria-based centrifugal ultrafiltration/liquid chromatography/mass spectrometry(LC/MS) method,also known as screening method for mitochondria-targeted bioactive constituents(SM-MBC). This method allowed searching natural mitochondria-targeting compounds from traditional Chinese medicines(TCMs), including Puerariae Radix(PR) and Chuanxiong Radix(CR). A total of 23 active compounds were successfully discovered from the two TCMs extracts. Among these 23 hit compounds, 17 were identified by LC/MS, 12 of which were novel mitochondria-targeting compounds. Among these, 6 active compounds were analyzed in vitro for pharmacological tests and found able to affect mitochondrial functions. We also investigated the effects of the hit compounds on Hep G2 cell proliferation and on loss of cardiomyocyte viability induced by hypoxia/reoxygenation injury. The results obtained are useful for in-depth understanding of mechanisms underlying TCMs therapeutic effects at mitochondria level and for developing novel potential drugs using TCMs as lead compounds. Finally, we showed that SM-MBC was an efficient protocol for the rapid screening of mitochondria-targeting constituents from complex samples such as PR and CR extracts.
文摘Objective High performance liquid chromatography(HPLC)and liquid chromatography-mass spectrometry(LC/MS)methods were developed for the determination of ganciclovir and its related substances.Methods A Hypersil ODS2 column(4.6 mm×250 mm,5 μm)was used with a mobile phase of 0.02 M potassium dihydrogen phosphate buffer(pH 6.0)-methanol(92∶8)at a flow rate of 1.0 mL/min,and UV detector set at 254 nm was used for monitoring the eluents.Results The method was simple,rapid,selective and capable of separating all related substances at trace level with a detection limit of 0.04 μg/mL.It has been validated with respect to accuracy,precision,linearity,and limits of detection and quantification.The linearity range was 10.2-153.0 μg/mL with r=0.9998.The percentage recoveries ranged from 96.7% to 101.6%,and RSD was 1.24%-1.96%(n=5).Conclusion The method was found to be suitable not only for monitoring the reactions during the process development but also for quality control of ganciclovir.For identification of related substances,LC/MS was used.The mainly related substances of ganciclovir active pharmaceutical ingredients(API)were determined as guanine,(1,3-dioxolan-4-yl)methyl acetate,and diacetyl guanine.
基金Supported by the Projects of the General Administration of Quality Supervision,Inspection and Quarantine of China(No.2007IK157)
文摘Eighteen sex hormones in antler velvet were determined by high performance liquid chromatography tandem mass spectrometry.The solid phase extraction was applied to eliminating the matrix effect.The experimental conditions were examined and optimized.Under the optimal conditions,the proposed method provides the good linearities and determination limits(0.2―1.0 μg/kg) of the analytes investigated.The recoveries ranging from 72.3% to 149.5% were obtained for the target analytes at two concentration levels.This method was applied to the determination of eighteen sex hormones in different kinds of antler velvet samples and the obtained results are satisfactory.The results indicate that the proposed method is suitable for the determination of sex hormones in antler velvet samples.
文摘A reliable,selective and sensitive liquid chromatography tandem mass spectrometry method was developed and validated for the quantification of lamotrigine in human plasma using lamotrigine13C3,d3 as an internal standard.Analyte and internal standard were extracted from human plasma by solid-phase extraction and detected in positive ion mode by tandem mass spectrometry with electrospray ionization(ESI) interface.Chromatographic separation was performed on a Chromolith s SpeedROD;RP-18e column(50-4.6 mm i.d.) using acetonitrile:570.1 mM ammonium formate solution(90:10,v/v) as the mobile phase at a flow rate of 0.500 mL/min.The calibration curves were linear over the range of 5.02-1226.47 ng/mL with the lower limit of quantitation validated at 5.02 ng/mL.The analytes were found stable in human plasma through three freeze(-20℃)-thaw(ice-cold water bath) cycles and under storage on bench-top in ice-cold water bath for at least 6.8 h,and also in the mobile phase at 10℃ for at least 57h.The method has shown good reproducibility,as the intra-and inter-day precisions were within 3.0%,while the accuracies were within 76.0% of nominal values.The validated LC-MS/MS method was applied for the evaluation of pharmacokinetic and bioequivalence parameters of lamotrigine after an oral administration of 50mg lamotrigine tablet to thirty-two healthy adult male volunteers.
基金the supports of the National Key Research and Development of BioBased Rubber(2017YFB0306900&2017YFB0306901)the National Natural Science Foundation of China(51673012)+1 种基金the Fundamental Research Funds for the Central Universities(PYBZ1828)the Beijing Technology and Business Universtiy Youth Scholoars Funds(PXM2019014213000007)。
文摘Taraxacum kok-saghyz(TKS)is rich in natural rubber(NR),a natural organic macromolecular compound composed of cis-1,4-polyisoprene,and may become the second NR-bearing plant for biochemical engineering development.In this paper,a rapid and quantitative ultra-high performance liquid chromatography tandem mass spectrometry(UHPLCMS/MS)method was established for determination of macromolecular biosynthesis substrate(dimethylallyl pyrophosphate,DMAPP)and initiator(farnesyl pyrophosphate,FPP)contained in TKS.A Kromasil C18 chromatographic column was used for separation,and the multi-reaction monitoring mode(MRM)of triple quadrupole mass spectrometry was used for detection.Quantification was performed by external calibration method.The results showed that the limit of detection(LOD)and the limit of quantitation(LOQ)of DMAPP were 2.42μg/L and 7.26μg/L,respectively,and the LOQ and the LOD of FPP were 1.02μg/L and 3.05μg/L,respectively.At a concentration of 1—1000μg/L,both analytes had good determination coefficients(>0.999)of calibration curve.The recoveries of DMAPP and FPP were between 99.0%and 117.1%.In real samples detection,the contents of DMAPP and FPP in TKS samples were between 23.32—82.77μg/L and 12.03—85.67μg/L,respectively.Thus,this approach is a reliable method to quantify DMAPP and FPP in TKS.
基金Hebei Provincial Key R&D Project(19227516D)Hebei Provincial Phase II Modern Agricultural Industry Technology System Innovation Team Building Project(HBCT2018120207,HBCT2018160403).
文摘[Objectives]A rapid screening and analysis method for 26 organophosphorus agrochemicals in fresh milk was established using ultra performance liquid chromatography coupled with quadrupole-time of flight mass spectrometry.[Methods]Raw milk was extracted with acetonitrile solution containing 0.2%formic acid by volume,and purified with a Dikma ProElut QuECHERS solid phase extraction cartridge.Target compounds were separated on a Waters ACQUITY UPLC HSS T3 chromatographic column(2.1 mm×50 mm,1.8μm)with methanol-water solution as a mobile phase for gradient elution,and through scanning with an electrospray ion source in positive ion mode,26 kinds of organophosphorus agrochemicals could be accurately qualitatively determined within 10 min.[Results]When using formic acid acetonitrile with a volume fraction of 0.2%,there were more types of detected compounds and a greater recovery;and using B cartridge could effectively eliminate the interference of non-polar substances such as phospholipids,achieve higher number of detected compounds than those of A and C,and well separate the 26 kinds of agrochemical residues.[Conclusions]This study provides a reference method for the rapid screening of agrochemical residues in dairy cows in the future.
基金Supported by the National Natural Science Foundation of China(No.30801513)the Knowledge Innovation Program of Chinese Academy of Sciences(No.KSCX2-YW-R-170)
文摘Centrifugal ultrafiltration after methanol extraction of whole plasma was used as an optimal condition for the preparation of blood plasma before metabonomic studies. The plasma samples from 102 lung cancer patients and 34 healthy volunteers were prepared with this approach. With ultra-performance liquid chromatography(UPLC) coupled with quadrupole time-of-flight mass spectrometry(Q-TOF MS) analysis, the samples were investigated in order to find potential disease biomarkers. After data acquisition, orthogonal signal correction partial least squares models were built to differentiate the healthy volunteers from lung cancer patients and to identify metabolites that showed significantly different expression between the two groups. Several metabolite ions were identified as potential biomarkers according to the variable importance in the project(VIP) value in both ion modes. Five lysophosphatidylcholines were further identified as specifically lysoPC 16:0, isomer of lysoPC 16:0, lysoPC 18:0, lysoPC 18:1 and lysoPC 18:2. These results suggest that UPLC coupled with Q-TOF MS is an effective technique for the analysis of plasma metabolites in metabonomic studies.
基金Supported by the National Key Scientific and Technological Project of China(No.2009ZX09502-012)the Research Fund for the Doctoral Program of Higher Education of China(No.20090101110126)the Zhejiang Province Science and Technology Plan Project,China(No.2008C23065)
文摘In order to identify the potential nephrotoxic compounds in traditional Chinese medicine Lithospermum erythrorhizon,it was separated into serial fractions according to their polarities.An in vitro method was utilized to determine the nephrotoxicity of these fractions with the help of fluorescence image analysis.As a result,the primary fraction A05 and its secondary fractions C06 "C09 and C12 "C14 were found to have significant toxicity to LLC-PK1 cell line,as determined by the survive rate less than 20% after they were treated with these fractions.These potential nephrotoxic fractions were further analyzed by multistage and high resolution mass spectrometry.The main compounds in these fractions were tentatively identified to be acetylshikonin,isobutyrylshikonin,β,β'-dimethyla-cryloylshikonin,and isovalerylshikonin,which may bring nephrotoxicity.
文摘The standards of plant toxins were separated by a C18 column with gradient elution with 0.1% formic acid/water (V/V) and 0.1% formic acid/acetonitrile (V/V) as mobile phase and acquired by ion mobility-quadrupole time of flight mass spectrometry (IM-QTOF MS) in positive ion mode. A database of 308 plant toxins including retention time, collision cross-section (CCS) and its fragment ions was established. Honey dissolved in water or herbal beverage was extracted by acetonitrile and purified with PSA sorbent, and then acquired by ultrahigh-performance liquid chromatography IM-QTOFMS. The acquired data were processed by comparing with the database we established to confirm the target compounds. The average recoveries for samples at two levels ranged from 60.6% - 120.1%, with relative standard deviation (n = 6) less than 25%. The limit of quantitation for plant toxins ranged from 1 - 20 μg/kg. The developed screening method was used in determination of honey, herbal beverage and honey flavored tea beverage samples. The results showed that berberine was detected in one honey with 1 μg/kg and caffeine was present in some beverages with the concentration from 200 and 5500 μg/kg. This method could meet the requirement for rapid screening of plant toxins in honey and herbal beverage. It can be used for the quality control of honey and herbal beverage in enterprises or quality inspection departments. It also can be used in the rapid screening of food poisoning.
基金supported by the National Natural Science Foundation of China,No.82101327(to YY)President Foundation of Nanfang Hospital,Southern Medical University,No.2020A001(to WL)+1 种基金Guangdong Basic and Applied Basic Research Foundation,Nos.2019A1515110150,2022A1515012362(both to YY)Guangzhou Science and Technology Project,No.202201020111(to YY).
文摘Microglia,the primary immune cells within the brain,have gained recognition as a promising therapeutic target for managing neurodegenerative diseases within the central nervous system,including Parkinson’s disease.Nanoscale perfluorocarbon droplets have been reported to not only possess a high oxygen-carrying capacity,but also exhibit remarkable anti-inflammatory properties.However,the role of perfluoropentane in microglia-mediated central inflammatory reactions remains poorly understood.In this study,we developed perfluoropentane-based oxygen-loaded nanodroplets(PFP-OLNDs)and found that pretreatment with these droplets suppressed the lipopolysaccharide-induced activation of M1-type microglia in vitro and in vivo,and suppressed microglial activation in a mouse model of Parkinson’s disease.Microglial suppression led to a reduction in the inflammatory response,oxidative stress,and cell migration capacity in vitro.Consequently,the neurotoxic effects were mitigated,which alleviated neuronal degeneration.Additionally,ultrahigh-performance liquid chromatography–tandem mass spectrometry showed that the anti-inflammatory effects of PFP-OLNDs mainly resulted from the modulation of microglial metabolic reprogramming.We further showed that PFP-OLNDs regulated microglial metabolic reprogramming through the AKT-mTOR-HIF-1αpathway.Collectively,our findings suggest that the novel PFP-OLNDs constructed in this study alleviate microglia-mediated central inflammatory reactions through metabolic reprogramming.
基金supported by the Research Fund for the Doctoral Program of Higher Education(No.20110002110052)
文摘Keto-enol tautomers of curcumin were confirmed by reversed-phase liquid chromatography(RPLC)/ hybrid quadrupole ion trap/time-of-flight mass spectrometry(QIT/TOFMS).Tautomers gave different MS/MS spectra in negative mode.Different mass spectra were also obtained by hydrogen/deuterium exchange LC/MS/MS in positive mode.Our results suggest that enol form is the major form in the solution(water/acetonitrile).
文摘Comprehensive two-dimensional liquid chromatography platform(LC×LC)coupled with quadrupole time-of-flight(QTOF)mass spectrometry(MS)is developed to separate,identify and relatively determine the chemical constituents of two types of tripterygium glycosides tablets(TGT).The types and relative contents of the constituents discovered in two kinds of TGT tablets were subsequently compared.C8andC18 column were used for the separation of the first
基金the Ministry of Public Health of the People's Republic of China(No200802038) for financial support
文摘In this paper, a high-performance liquid chromatography coupled with ultraviolet detection and Fourier transform-ion cyclotron resonance mass spectrometry (HPLC-UV/FrICRMS) method was described for the investigation of impurity profile in moxifloxacin (MOX) drug substance and chemical reference substance. Ten impurities were detected by HPLC-UV, while eight impurities were identified by using the high accurate molecular mass combined with multiple-stage mass spectrometric data and fragmentation rules. In addition, to our knowledge, five impurities were founded for the first time in MOX drug substance.
基金supported by the National Science and Technology Major Project of China “Key New Drug Creation and Manufacturing Program” 2015ZX09501004-001-007National Natural Science Foundation of China 82004082Top talent training project of TCM in Henan Province。
文摘Objective: To compare the pharmacokinetic differences of the main components of Naoxintong capsule(NXTC) in normal and acute blood stasis rats. Materials and Methods: Rats were subcutaneously injected with adrenaline hydrochloride twice;during the two subcutaneous injections, the rats were placed in ice water for 4 min to reproduce the model rat of acute blood stasis. The normal and acute blood stasis rats were administrated a 5.04 g/kg dose of NXTC suspension. Then, blood samples were collected from the posterior retinal venous plexus at different time points. Plasma concentrations of four major bio-active components including caffeic acid, ferulic acid, formononetin, and tanshinone IIA in NXTC were measured using ultra-performance liquid chromatography coupled with triple-quadrupole mass spectrometry. Phoenix Win Nonlin v6.2 software was used to calculate the pharmacokinetic parameters. Results: Compared with the normal rats, the acute blood stasis rats showed a significant decrease in C_(max) of ferulic acid and formononetin, AUC_(all) of caffeic acid and ferulic acid, and AUC_(INF_obs) of ferulic acid. Conversely, an increase in the Vz_F_obs and MRT_(last) of ferulic acid and caffeic acid was observed. These findings demonstrate that the absorption of the four NXTC components was weakened in the acute blood stasis rats and that the elimination time was prolonged. Conclusions: The significant difference in some parameters of the four NXTC components between the normal and acute blood stasis rats might be caused by an increase in blood viscosity and the subsequent slowing down of blood flow in the acute blood stasis rats. The pharmacokinetic study conducted in pathological state can provide important information and scientific basis for further rational clinical application of NXTC.
基金supported by the National Key Research and Development Project(SQ2018YPC170480,2018YFC1708202)the National Natural Science Foundation of China(81774009)+1 种基金the Key science and technology projects of Inner Mongolia Autonomous Region(2019ZD004)Open Project Program of Inner Mongolia Key Laboratory of Toxicant Monitoring and Toxicology,China(MDK 2019040)。
文摘Objective:There are different geographic origins of Aconiti Kusnezoffii Radixs(AKRs)sold in the market with different quality.This study aims to establish a rapid analysis method to distinguish the different geographic origins of AKRs and to realize the rapid evaluation of their quality.Methods:An ultra-performance liquid chromatography coupled with time-of-flight mass spectrometry(UPLC-Q-TOF MS)method was utilized to acquire the constituents'information of AKRs from different geographic origins.MSE data and Progenesis QI software were employed to identify the chemical constitutes.Principal component analysis(PCA)was applied to comparing MS data to find the chemical markers of AKRs from different geographic origins.Results:Twenty-three components were detected and 17 out of them were identified,including diester-diterpenoid alkaloids,monoester-diterpenoid alkaloids,and amine-diterpenoid alkaloids.Three pairs of isomers were detected and two of them were distinguished by the retention time of standard samples.Thirteen chemical markers were screened out through PCA and orthogonal partial least square discriminant analysis.Through detecting Napelline or isomer of Napelline(m/z 360.2530)and Aconifine(m/z 662.3170),AKRs from inner Mongolia autonomous could be screened.According to the existence of benzoylaconine(m/z 604.3108)and Indaconitine(m/z 630.3159),it could be confirmed that the AKRs are from Xinjiang Uygur autonomous.AKRs that cannot detect compounds above-mentioned could be from Liaoning or Shanxi Province.Conclusions:The chemical profile could be used not only to distinguish the AKRs from different geographic origins but also to identify the true and false of AKRs.This study lays a foundation for the study of efficacy and toxic of AKRs.
基金supported financially by the National Natural Science Foundation of China (Grant No. 81973604, 81803690and 81703684)the Innovative Talents Funding of Heilongjiang University of Chinese Medicine(Grant No.2018RCD25)+8 种基金the National natural science foundation matching project (Grant No. 2018PT02)the National natural Science Foundation Matching Project (Grant No. 2017PT01)the Graduate Innovative Research Project Foundation of Heilongjiang University of Chinese Medicine (Grant No. 2019yjscx013)the Postdoctoral Initial Fund of Heilongjiang Provincethe University Nursing Program for Young Scholars with Creative Talents in Heilongjiang Province (Grant No. UNPYSCT2017215 and UNPYSCT2017219)the Natural Science Foundation of Heilongjiang Province (Grant No. H2015037)the Heilongjiang University of Chinese Medicine Doctoral Innovation Foundation (Grant No. 2014bs05)the Application Technology Research and Development Projects of Harbin Technology Bureau (Grant No. 2014RFQXJ149)Heilongjiang Postdoctoral Scientific Research Developmental Fund (Grant No.LBHQ16210 and LBH-Q17161)
文摘A rapid and high selective ultra-performance liquid chromatography(UPLC)with tandem mass spectrometry method for simultaneous determination of six compounds including albiflorin,paeoniflorin,picroside I,picroside II,saikosaponin A,and saikosaponin D in rat plasma was developed and validated using butyl p-hydroxybenzoate as an internal standard.One-step direct protein precipitation with acetonitrile was used to extract the compounds from the rat plasma samples.Chromatographic separation was achieved using an ACQUITY UPLC BEH C18 column(100 mm×2.1 mm,1.7μm)at a flow rate of 0.4 m L/min,using gradient mode containing 0.1%formic acid in water and acetonitrile were used as the Mobile phase A and B.Electrospray ionization in negative ion mode and multiple reaction monitoring were used to identify and quantify active components.Calibration curves showed good linearity(R^2>0.9908)over a wide concentration range for all compounds.The intra-and interday precision(relative standard deviation)ranged 2.4%–7.0%and 2.6%–8.0%,respectively.The accuracy(relative error)was from-13.0%to 13.2%at all quality control levels.The recovery ranged from 81.1%to 92.5%.The validated method was successfully applied to pharmacokinetic study in rats after oral administration of Qing Gan-Shu Yu-Fang.The results show that one can draw a conclusion that these six active ingredients can be quickly absorbed and play a pharmacodynamic role rapidly in vivo.
文摘A rapid and sensitive liquid chromatography tandem mass spectrometry(LC-MS/MS) method has been developed and validated for the determination of moxifloxacin(MOXI) in human plasma. After a simple protein precipitation using acetonitrile, the post treatment samples were analysed on a C18 column interfaced with a Triple Quadropole Tandem Mass Spectrometer. Positive electrospray ionization was employed as the ionization source. The mobile phase consisted of 0.1% formic acid–acetonitrile(60:40, v/v). Ciprofloxacin(CIPRO) was used as an internal standard. The analyte and internal standard(CIPRO) were monitored in the multiple reaction monitoring mode(MRM). The mass transition ion-pair has been followed as m/z 402→358.2 for MOXI and 332→288.1 for CIPRO. The method was linear in the concentration range of 25–5000 ng/mL. The lower limit of quantification was 25 ng/mL. The intra- and inter-day precision(relative standard deviation) and accuracy(relative error) values were within 12.4%. Each plasma sample was analyzed within 3 min.
基金supported by the National Nature Science Foundation of China (No.21075074)
文摘Aspartame is a widely used sweetener, the long-term safety of which has been controversial ever since it was accepted for human consumption. It is unstable and can produce some harmful degradation products under certain storage conditions. A high-performance liquid chromatography/tandem mass spectrometry method was developed for the simultaneous analysis of aspartame and its four degradation products, including aspartic acid, phenylalanine, aspartyl-phenylalanine and 5-benzyl-3,6- dioxo-2-piperazieacetic acid in water and in diet soft drinks. Aspartame and its four degradation products were quantified by a matrix matched external standard calibration curve with excellent correlation coefficients. The limits of detection were 0.16-5.8 μg/L, which exhibited higher sensitivity than common methods. This method was rapid, sensitive, specific and capable of eliminating matrix interferences. It was also applied to the study of the degradation of aspartame at various pH and temperatures. The results indicated that aspartame was partly degraded under strong acidic or basic conditions and the extent of degradation increased with increasing temperature.
基金supported by the Project of the National Natural Sciences Foundation of China(81373239).
文摘A simple,rapid and sensitive liquid chromatography with tandem mass spectrometry method for the determination of periplocymarin in human blood and urine was developed.The digoxin‑d3 was used as an internal standard.Periplocymarin and digoxin‑d3(IS)were processed with ethyl acetate by liquid–liquid extraction.The chromatographic separation was performed on a Shim‑pack XR‑ODSIII C18 column with a 7 min gradient elution using methanol‑ammonium formate(5 mmol/L)as mobile phase at a flow rate of 0.3 mL/min(65:35,v/v).The detection was performed on a triple quadrupole tandem mass spectrometer using positive‑ion mode electrospray ionization in selected reaction monitoring mode.The periplocymarin was well separated from the internal standard.Two calibration curves were linear within the concentration range 0.01–1µg/mL.The limit of detection and quantification of blood and urine samples were both estimated at 0.005 and 0.01µg/mL.The interday and intraday precisions,accuracy,and recovery were assessed to verify this method.The results showed that the method was suitable for the determination of periplocymarin in forensic toxicological analysis and clinical diagnosis.