Novel method for the determination of five carbamate pesticides in water samples by dispersive liquid-liquid microextraction combined with high performance liquid chromatography

A novel method for the determination of five carbamate pesticides （metolcarb, carbofuran, carbaryl, isoprocard and diethofencard） in water samples was developed by dispersive liquid-liquid microextraction （DLLME） coupled with high performance liquid chromatography-diode array detector （HPLC-DAD）. Some experimental parameters that influence the extraction efficiency were studied and optimized to obtain the best extraction results. Under the optimum conditions for the method, the calibration curve was linear in the concentration range from 5 to 1000 ng mL^-1 for all the five carbamate pesticides, with the correlation coefficients （r^2） varying from 0.9984 to 0.9994. Good enrichment factors were achieved ranging from 80 to 177- fold, depending on the compound. The limits of detection （LODs） （S/N = 3） were ranged from 0.1 to 0.5 ng mL^-1. The method has been successfully applied to the analysis of the pesticide residues in environmental water samples.

Rapid Determination of Dopamine and Its Metabolites During in vivo Cerebral Microdialysis by Routine High Performance Liquid Chromatography With Electrochemical Detection

To determine dopamine and its metabolites during in vivo cerebral microdialysis by routine high performance liquid chromatography with electrochemical detection. Methods Microdialysis probes were placed into the right striatum of Wistar rat brains and perfused with Ringer＇s solution at a rate of 1.5 pL/min. A reverse phase HPLC with electrochemistry was used to assay DA, DOPAC, and HVA after cerebral microdialysates were collected every 20 minutes from awake and freely moving rats. In order to identify the reliability of this method, its selectivity, linear range, precision and accuracy were tested and the contents of DA, DOPAC, and HVA in rat microdialysates were determined. Results The standard curve was in good linear at the concentration ranging from 74 nmol/L to 1.5 pmol/L for DOPAC （r^2= 0.9996）, from 66 nmol/L to 1.3 gmol/L for DA （r^2=l.0000） and from 69 nmol/L to 1.4 pmol/L for HVA （r^2=0.9992）. The recovery of DOPAC （0.30, 0.77, 1.49 gmol/L）, DA （0,26, 0.69, 1.32 gmol/L）, and HVA （0.27, 0.71, 1.37 gmol/L） was 82.00±1.70%, 104.00±4.00%, 98.70±3.10%; 92.30± 1.50%, 105.30±2.30%, 108.00±2.00%; 80.00±7.80%, 107.69±8.00%, and 108.66±3.10%, respectively at each concentration. Their intra-day RSD was 3.3%, 3.4%, and 2.5%, and inter-day RSD was 4.2%, 2.3%, and 5.6%, respectively. The mean extracellular concentrations of DOPAC, DA, and HVA in rat brain microdialysates were 10.7, 2.4, and 9.2 gmol/L （n=6）, respectively. Conclusion The findings of our study suggested that the simple, accurate and stable method can be applied to basic researches of diseases related to monoamines neurotransmitters by cerebral microdialysis in rats.

Trace Determination of Tamoxifen in Biological Fluids Using Hollow Fiber Liquid-Phase Microextraction Followed by High-Performance Liquid Chromatography-Ultraviolet Detection

The applicability of hollow fiber liquid-phase microextraction (HF-LPME) combined with high-performance liquid chromatography-ultraviolet detection (HPLC-UV) was evaluated for the extraction and determination of tamoxifen (TAM) in biological fluids including human urine and plasma. The drug was extracted from a 15 mL aqueous sample (source phase;SP) into an organic phase impregnated in the pores of the hollow fiber (membrane phase;MP) followed by the back-extraction into a second aqueous solution (receiving phase;RP) located in the lumen of the hollow fiber. The effects of several factors such as the nature of organic solvent, compositions of SP and RP solutions, extraction time, ionic strength and stirring rate on the extraction efficiency were examined and optimized. An enrichment factor of 360 along with substantial sample clean up was obtained under the optimized conditions. The calibration curve showed linearity in the range of 1 - 500 ng?mL–1 and the limit of detection was found to be 0.5 ng?mL–1 in aqueous medium. A reasonable relative recovery (≥89%) and satisfactory intra-assay (3.7% - 4.2%, n = 3) and inter-assay (7.5% - 7.8%, n = 3) precision illustrated good performance of the analytical procedure in spiked human urine and plasma samples.

Comparison of protocatechuic aldchyde in Radix Salvia miitiorrhiza and corresponding pharmacological sera from normal and fibrotic rats by high performance liquid chromatography

瞄准：在肝的星形细胞(HSC ) 的增长上观察 protocatechuic aldchyde 的效果。方法：肝纤维变性被四氯化碳(CCl4 ) 在老鼠导致。然后正常、纤维变性的药重量的单位一从老鼠被提取。protocatechuic aldchyde，未加工的根值鼠尾草植物 miltiorrhiza 和药重量的单位的效果 HSC 生长上的 of 鼠尾草植物 miltiorrhiza 被 CCK-8 决定。protocatechuic aldchyde 被高效液相色谱法(HPLC ) 在 Alltima C18 列分开(250 公里 mult 4.6 公里， 5 microm ) 与在 281 nm 的波长的 acetonitrile-4% 冰乙酸答案(坡度洗脱) 的一个活动阶段。结果：of 鼠尾草植物 miltiorrhiza 被发现在老鼠 HSC 的增长上有禁止的效果的 Protocatechuic aldchyde，未加工的根值鼠尾草植物 miltiorrhiza 和药重量的单位。未加工的根值鼠尾草植物 miltiorrhiza 比药重量的单位有更强壮的禁止的效果一。纤维变性药重量的单位一比正常的药重量的单位显示出更高镇压的效果一(P 【 0.05 ) 。Protocatechuic aldchyde 在两根值鼠尾草植物 miltiorrhiza 和它的相应的药重量的单位的粗略的材料被发现一。平均恢复(n = 6 ) 为未加工的鼠尾草植物 miltiorrhiza Bge 是 110.5% ， 102% 为正常的药重量的单位一 and 105.2% 为纤维变性药重量的单位一。相对标准 devitation (RSD ) 是 0.37% ， 1.96% 和 1.51% ，分别地(n = 6 ) 。protocatechuic aldchyde 的内容是 0.22% ， 0.15% 和 0.19% ，分别地(n = 6 )(P 【 0.05 ) 。RSD 是 0.33% ， 0.75% 和 1.24%(n = 6 ) 为根值鼠尾草植物 miltiorrhiza 的原料，正常的药重量的单位一个 and 纤维变性药重量的单位一分别地。样品为 6 d 是稳定的。结论：Protocatechuic aldchyde 能禁止 HSC 的生长。HPLC 对中草药在试管内的虚拟简历有功成分的决心合适。

Development of a Fast and Facile Analytical Approach to Quantify Radiometabolites in Human Plasma Samples Using Ultra High Performance Liquid Chromatography

Introduction: Conventional metabolite analyses often require manual sample preparation, generating variability of measurements. This study describes a new method to quantify radiometabolites in blood, combining ultra high performance liquid chromatography (UHPLC) and turbulent flow chromatography, an alternative fully automated process allowing analyte’s extraction. Methods: A new radiotracer for dopamine transporter imaging, namely LBT-999, was used to demonstrate the method’s robustness. Matrix effect, Turboflow column loading, linearity, specificity and precision were evaluated with in vitro samples of LBT-999 in human plasma. Radiodetector sensitivity and preliminary evaluation were respectively determined by analysis of calibrated samples of [18F]LBT-999 and blood samples from 4 healthy subjects injected with [18F]LBT-999, withdrawn at 5, 15, 30 and 45 min pi. Results: With three sequential loadings (3 × 100 μL) of the Turboflow column, mean coefficients of variation were 1%, below 2%, 2% and 30.9% for matrix effect, specificity, repeatability and intermediate precision, respectively. Correlation coefficients for linearity were superior to 0.97. Limits of detection and quantification of the radiodetector were fixed at 3 and 9 c/s. Retention times for [18F]LBT-999 and the two radiometabolites detected by radio-UHPLC were 6.5, 4.8 and 9.6 min. Forty-five min after the injection, parent fraction was still predominant with 57.8% ± 25% of the total radioactivity. Conclusions: An innovative approach, allying UHPLC and Turboflow column, was developed and its sensitivity, linearity, specificity and repeatability validated. Preliminary results of the clinical trial are in accordance with literature data, demonstrating its efficiency in radiometabolites quantification.

Advancements in the preparation of high-performance liquid chromatographic organic polymer monoliths for the separation of small-molecule drugs

The various advantages of organic polymer monoliths, including relatively simple preparation processes,abundant monomer availability, and a wide application range of pH, have attracted the attention of chromatographers. Organic polymer monoliths prepared by traditional methods only have macropores and mesopores, and micropores of less than 50 nm are not commonly available. These typical monoliths are suitable for the separation of biological macromolecules such as proteins and nucleic acids, but their ability to separate small molecular compounds is poor. In recent years, researchers have successfully modified polymer monoliths to achieve uniform compact pore structures. In particular, microporous materials with pores of 50 nm or less that can provide a large enough surface area are the key to the separation of small molecules. In this review, preparation methods of polymer monoliths for high-performance liquid chromatography, including ultra-high cross-linking technology, post-surface modification, and the addition of nanomaterials, are discussed. Modified monolithic columns have been used successfully to separate small molecules with obvious improvements in column efficiency.

Imidazolium ionic liquid as the background ultraviolet absorption reagent for determination of morpholinium cations by high performance liquid chromatography-indirect ultraviolet detection

A novel analytical method was developed for determining morpholinium cations lacking ultraviolet absorption groups.This determination was carried out by high performance liquid chromatographyindirect ultraviolet（HPLC-1UV） detection using imidazolium ionic liquid as background absorption reagents,and imidazolium ionic liquid aq.soln.-organic solvent as mobile phase by a reversed-phase C18 column.The background ultraviolet absorption reagents,imidazolium ionic liquids and organic solvents were investigated.The imidazolium ionic liquid in the mobile phase is not only the background ultraviolet absorption reagent for IUV,but also an active component to improve the separation of morpholinium cations.It was found that morpholinium cations could be adequately determined when0.5 mmol/L 1-ethyl-3-methylimidazolium tetrafluoroborate aq.soln./methanol（80：20,v/v） was used as mobile phase with an IUV detection wavelength of 210 nm.In this study,the baseline separation of Nmethyl,ethylmorpholinium cations（MEMo） and N-methyl.propylmorpholinium cations（MPMo） was successfully achieved in 8.5 min.The detection limits（S/N = 3） for MEMo and MPMo were 0.15 and0.29 mg/L,respectively.This simple and practical method has been successfully applied to the determination of two morpholinium ionic liquids synthesized by the chemistry laboratory.

Separation and identification of moxifloxacin impurities in drug substance by high-performance liquid chromatography coupled with ultraviolet detection and Fourier transform ion cyclotron resonance mass spectrometry

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.

Chromatographic fingerprint analysis of Fructus Aurantii Immaturus by HPLC-DAD and chemometric methods

An efficient method for quality control of Fructus Aurantii Immaturus (FAI),a famous traditional Chinese medicine (TCM) was established. A simple and reliable high-performance liquid chromatography-photodiode array detector (HPLC-DAD) procedure coupled with chemometric methods was developed for fingerprint analysis,qualitative analysis and quantitative determination of this herb. In qualitative and quantitative analyses,heuristic evolving latent projection (HELP) method was employed to resolve the overlapping peaks of the tested samples. Two bioactive components,namely hesperidin and naringin,are confirmed and determined,together with four flavonoids compounds tentatively identified including two new ones. From fingerprint analysis,the fingerprint data were processed with correlation coefficients for quantitative expression of their similarity and dissimilarity. The developed method based on an integration of chromatographic fingerprint and quantitative analysis is scientific,and the obtained results can be applied to the quality control of herb medicine.

Development and Validation of a Method for Simultaneous Determination of Metformin Hydrochloride and Sitagliptin Phosphate in a Formulation by RP-HPLC

Present study was aimed to develop and validate a reverse-phase high-performance liquid chromatography method for simultaneous determination of sitagliptin phosphate and metformin hy-drochloride in a marketed formulation. The drug separation was performed on Hibar-240, Li-chrosphere-100 C18 ODS (250 × 4.6 mm, 5 μm) column, at a flow rate of 1 mL/min. The mobile phase used was a mixture of methanol: potassium di-hydrogen phosphate buffer at a ratio of 70:30 v/v. The detection was carried out at a wavelength of 266 nm. The retention times of sitagliptin phosphate and metformin hydrochloride were found as 6.1 and 4.9 min respectively. Linear calibration curves with good correlation coefficients were obtained over the concentration ranges of 10 - 50 μg/mL for sitagliptin and 20 - 100 μg/mL for metformin. The limit of detection was 0.016 and 0.14 μg/mL and the limit of quantification was 0.048 and 0.42 μg/mL for sitagliptin phosphate and metformin hydrochloride respectively. Validation of the method demonstrated system selectivity, specificity, linearity, accuracy and precision. The developed method was found useful in the simultaneous analysis of sitagliptin phosphate and metformin hydrochloride in formulation.

Qualitative and Quantitative Analysis of Five Bioactive Flavonoids in <i>Salix bordensis</i>Turcz. by HPLC-DAD and HPLC-ESI-MS

The qualitative characterization and quantitative analysis of five bioactive flavonoids in Salix bordensis Turcz. were achieved via reversed-phase high-performance liquid chromatography coupled with diode array detection and tandem mass spectrometry, by using an Agilent ZORBAX SB-C18 HPLC column with a gradient elution of 0.3% (v/v) formic acid in water and methanol as the mobile phase. The compounds in the mixture were clearly identified by comparing their HPLC-DAD ultraviolet spectra, retention times, and MS data with those of corresponding reference compounds. All calibration curves showed good linearity (r2 > 0.9998) within the test ranges. The LOD, LOQ, specificity, precision, and accuracy for the method were validated. The results demonstrated that this analytical approach is ideal for the determination of bioactive compounds, such as flavonoids, and that it constructed a basis for the comprehensive evaluation of the quality of Salix bordensis Turcz.

固相萃取-一标多测高效液相色谱法测定化妆品中5种苯并三唑类防晒剂

建立了固相萃取技术结合高效液相色谱测定化妆品中5种苯并三唑类防晒剂的一标多测定量分析方法。该方法待测样品使用HLB固相萃取小柱净化处理,以亚甲基双-苯并三唑基四甲基丁基酚为内参物,通过建立该物质与另外4种物质的相对校正因子,计算出各物质的含量。研究了不同进样量、不同流动相流速及不同柱温对相对校正因子的影响,比较了一标多测法和外标法的计算结果。结果表明,5种物质的线性关系良好(R^(2)≥0.9997),检测限和定量限分别为4.00~26.43μg/L和10.00~60.42μg/L;各物质的相对校正因子重复性较好,其相对标准偏差(RSD)为0.25%~1.16%;两种方法计算结果无明显差异,其相对平均偏差(RAD)为0.12%~2.19%。该方法操作简单,使用标准物质少,检测效率高,可用于化妆品中5种防晒剂的含量测定和质量控制。

高效液相色谱-串联质谱法检测牛组织和奶中咪多卡残留的研究

建立了一种检测牛组织和牛奶中咪多卡残留检测的高效液相色谱-串联质谱法。牛组织(肌肉、肝脏、肾脏、脂肪)和奶在NaAc缓冲体系中酶解,经HCl溶液提取,WCX固相萃取柱净化,以0.3%甲酸水溶液(含20 mM甲酸铵)和0.3%甲酸乙腈为流动相进行梯度洗脱,在HILIC色谱柱上分离,在电喷雾正离子(ESI^(+))模式下,用多反应监测(MRM)模式检测,同位素内标法定量。结果表明:咪多卡在2.5~1000 ng/mL的浓度范围内呈现良好线性关系,相关系数(R^(2))大于0.99;咪多卡在牛组织和奶中的检测限均为10μg/kg,定量限均为20μg/kg;咪多卡在牛组织和奶中20~4000μg/kg添加浓度水平上的回收率在70.9%~109%范围内;批内RSD在0.55%~9.59%之间,批间RSD在2.21%~12.1%之间。该方法具有灵敏度高、定量准确,重复性好等特点,可以满足牛组织和奶中咪多卡残留检测的要求。

高效液相荧光色谱法同时测定六神曲中黄曲霉毒素、玉米赤霉烯酮和赭曲霉毒素A

目的建立一种用免疫亲和柱净化-柱后光化学衍生-高效液相色谱同时检测六神曲中黄曲霉毒素、玉米赤霉烯酮和赭曲霉毒素A的方法。方法样品采用60%乙腈超声提取,免疫亲和柱净化,采用XBridge^(®)Phenyl苯基色谱柱(4.6 mm×250 mm,5μm),以乙腈和0.1%磷酸溶液为流动相,梯度洗脱,光化学衍生仪衍生,通过切换荧光波长检测。结果黄曲霉毒素、玉米赤霉烯酮和赭曲霉毒素A标准曲线的线性范围分别为0.006~0.108、0.500~2.500和0.202~1.009 ng,6种毒素的线性关系在0.9994以上,检出限分别为1.2、100.0和40.3 ng/ml,平均加标回收率为73.2%~92.3%,相对偏差为2.1%~5.4%。结论该方法具有专属性强、操作方便等特点,能够有效用于六神曲中3种毒素的同时检测和安全质量控制。

配合饲料中64种药物超高效液相色谱-三重四极杆串联质谱检测方法的研究

[目的]建立同时检测配合饲料中64种药物的超高效液相色谱-三重四极杆串联质谱(ultra-high performance liquid chromatography-triple quadrupole tandem mass spectrometry,UHPLC-MS/MS)法,提高非法添加物的检测效率。[方法]采用Waters HSS T3型色谱柱(2.1 mm×100 mm,1.8μm)进行分离,流动相A为0.1%甲酸水溶液,流动相B为含0.1%甲酸的乙腈溶液,梯度洗脱,流速为0.40 mL/min,进样量为2μL;采用电喷雾离子源正离子扫描模式进行检测,多反应监测模式进行信号采集。比较4种样品提取溶剂以及2种固相萃取柱处理对目标药物的回收率,确定样品前处理的最佳方法。利用建立的UHPLC-MS/MS法对宁夏回族自治区不同来源的100批次配合饲料样品进行64种药物检测。[结果]配合饲料样品均质后,用含0.2%甲酸的乙腈水溶液(乙腈∶水=8∶2,V/V)提取,利用Oasis PRiME HLB型固相萃取柱对样品净化,多数目标药物的回收率在60%以上。64种药物在浓度为5.0~200.0μg/L的范围内线性关系良好,相关系数(R)均大于0.99;不同药物的定量限在5.0~10.0μg/kg;阳性添加5.0、20.0、50.0μg/kg 3个浓度的平均回收率在41.00%~120.49%,批内相对标准偏差(RSD)在0.54%~15.94%,批间RSD在1.25%~13.64%。在100个批次的配合饲料样品中均未检出目标药物。[结论]建立的UHPLC-MS/MS法线性关系良好、回收率高、精密度好,具有较高的重现性和较好的可操作性,可用于配合饲料中非法添加64种药物的筛查。

UPLC-MS/MS法检测3种食品中松仁过敏原

基于食品基质中松仁过敏原Pin k 2建立了一种超高效液相色谱-串联质谱法。将松仁经过研磨、脱脂、浸提、酶解后经Easy-nLC 1000-QExactive高分辨质谱仪进行分离分析,结合Uniprot蛋白数据库以及ProteinPilotTM软件对质谱图进行数据处理,经BLAST验证特异性,最终筛选3条松仁特异性肽段。方法学验证结果表明,方法在0.001~50mg/mL范围内线性关系良好,定量限为1mg/kg;在饼干、巧克力和饮料3种空白基质中的平均回收率为88.50%~107.57%,相对标准偏差不高于6.08%,基质效应为89.77%~96.13%。该方法具有灵敏度高、特异性好的优势,可应用于饼干、巧克力、饮料等食品样品中松仁过敏原的检测,为我国食品标签真实性检验及食品中隐性过敏原的检测提供技术支持。

高效液相色谱法测定室温下硝酸甘油注射液的存贮期限

目的高效液相色谱法测定硝酸甘油注射液在室温下的含量变化,预测硝酸甘油注射液在室温下的存贮期限。方法(1)HPLC法测定硝酸甘油注射液的含量。采用色谱柱(Kromasil C18),以甲醇:水(59:41)为流动相,流速1.0 ml·min^(-1),检测波长215 nm,柱温30℃;(2)采用加速试验和长期留样试验对硝酸甘油注射液的稳定性进行研究,经典恒温试验预测其在室温下的有效期。结果硝酸甘油注射液检测浓度在10μg·ml^(-1)-600μg·ml^(-1)范围内与峰面积呈良好的线性关系(R=0.9999),日内精密度、日间精密度、稳定性试验、重复性实验RSD均小于2%,含量测定平均值在99.99μg·ml^(-1)(标准值100μg·ml^(-1)),加样回收率RSD为1.67%。经典恒温试验测得硝酸甘油的含量变化符合一级反应规律,在25℃,硝酸甘油注射液的速率变化常数K_(25)=7.1395×10^(-4),有效贮存期限为147 d;在30℃时,K_(30)=9.4175×10^(-4),有效贮存期限为111 d。长期留样观察实验可以验证该实验的可靠性。结论高效液相色谱法检测方法简单、快速、精密度高,重复性好。硝酸甘油注射液在室温(25℃)下的存储期限约5个月,可以为临床管理抢救车药品提供参考依据。

高效液相色谱及其串联质谱技术在牙膏风险物质分析中的应用

牙膏是日常生活中必不可少的口腔清洁护理用品,牙膏的基料较为复杂,牙膏中潜在的风险物质对人体存在一定危害,因此牙膏产品的安全性已成为当今社会关注的焦点之一。利用现代先进的检验检测技术对牙膏中潜在的风险物质进行分析、研究,将有利于实现对牙膏产品的安全监管,本文综述了近几年来高效液相色谱及其串联质谱技术在牙膏产品检验标准和检验方法开发等方面的研究以及应用进展,一定程度上能为牙膏产品的质量控制和科学监管提供参考。

不同产地杜仲叶活性成分的定量分析

通过杜仲叶中主要活性成分绿原酸的提取率,优化杜仲叶活性成分的提取工艺,比较不同产地杜仲叶组成及含量的差异.以绿原酸为目标产物,通过单因素实验和Box-Behnken模型,并采用高效液相色谱法测定秦仲叶和华仲叶中芦丁、松脂醇二葡萄糖苷、金丝桃苷、绿原酸及没食子酸五种活性成分含量.单因素条件对两者叶的提取效果影响均为:提取温度>提取时间>乙醇体积分数>料液比.在最佳提取条件下,秦仲叶绿原酸提取率为62.94%,华仲叶绿原酸提取率为47.84%.两者叶中绿原酸含量最高,秦仲叶中芦丁、松脂醇二葡萄糖苷含量比华仲叶高出1.97倍和6.59倍,但华仲叶中金丝桃苷和绿原酸含量比秦仲叶高出1.41倍和1.16倍.本研究旨在为不同地域杜仲树种的选育以及临床上应用标准提供理论依据,帮助更加全面地评价不同产地杜仲药材质量.

九蒸九制对鸡头黄精理化性质及抗氧化性的影响

为了探究蒸制处理对鸡头黄精有效成分及代谢物种类和含量影响,采用低场核磁、苯酚-浓硫酸法、高效液相色谱-蒸发光散射检测法(HPLC-ELSD)和液相色谱-质谱技术(LC-MS)等对其中的水分分布、多糖含量、单糖组成和代谢产物等进行分析。结果表明,多次蒸制后,鸡头黄精结合水的含量、多糖含量逐渐降低,水提液pH值逐渐降低呈弱酸性达到4.07,还原糖、总酚、黄酮含量逐渐升高分别达到28.69%、10.02 mg/g和0.69%,抗氧化性逐渐增强,ABTS抗氧化能力在7制达到最高为0.73 mmol/L,较1制增加0.35 mmol/L,DPPH自由基清除率和FRAP值在8制达到最高分别为81.95%,1.97 mmol/L,较1制分别增加50.92%,1.72 mmol/L;同时蔗糖逐渐水解从18.53mg/g到7.62mg/g,葡萄糖和果糖含量提高,分别由1制0.00和11.30mg/g,达到9制17.25和230.89 mg/g。选取一制与九制黄精进行代谢物差异分析,在正离子模式下共检测到1310种代谢物,差异代谢物有176种(按其特性分为38类),在负离子模式下共检测到1841种代谢物,差异代谢物有148种(按其特性分为26类)。黄精经蒸制后有效成分差异性显著,对鸡头黄精炮制加工提供科学依据。