超高效液相色谱-四极杆飞行时间质谱法测定血液与尿液中赛拉嗪及代谢产物2,6-二甲基苯胺

建立了一种超高效液相色谱-串联四极杆飞行时间质谱同时测定血液和尿液中赛拉嗪及2,6-二甲基苯胺的分析方法。样品经乙酸乙酯-正己烷(1∶1,体积比)提取,C18色谱柱分离,电喷雾正电离条件下进行全离子扫描模式检测。借助分析软件,通过对化合物离子精确质荷比、同位素轮廓丰度、特征二级质谱以及保留时间的比对,对目标物进行验证。方法的回收率为72.5%~87.8%,相对标准偏差为6.8%~9.7%。赛拉嗪在血液和尿液中的检出限分别为0.2,0.1μg/L,定量下限分别为0.6,0.3μg/L;2,6-二甲基苯胺在血液和尿液中的检出限分别为0.5,0.3μg/L,定量下限分别为1.5,1.0μg/L。方法快速、灵敏度高、重现性好,适用于中毒人体的血液和尿液中赛拉嗪及2,6-二甲基苯胺的检测。     

液相色谱-串联质谱法测定尿液中的泛酸

该文建立了检测尿液中泛酸含量的液相色谱-串联质谱(HPLC-MS/MS)方法,尿液经过离心、稀释后,采用ACPUITY UPLC SS T3(2.1 mm×100 mm,1.8μm)色谱柱进行分离,电喷雾正离子模式电离,多反应监测模式进行检测,方法的线性关系良好(r=0.999 3),方法检出限为0.46 ng/m L,回收率为87.9%~95.3%,相对标准偏差(RSD)为2.5%~13.0%。该方法具有灵敏度高、分析时间短等特点,可用于尿液中泛酸含量的分析。     

Identification of metabolites in human and rat urine after oral administration of Xiao‐Qing‐Long‐Tang granule using ultra high performance liquid chromatography combined with quadrupole time‐of‐flight mass spectrometry

Xiao‐Qing‐Long‐Tang is a traditional Chinese formula used for the treatment of cold syndrome, bronchitis, and nasal allergies for thousands of years. However, the in vivo integrated metabolism of its multiple components and the active chemical constituents of Xiao‐Qing‐Long‐Tang remain unknown. In this study, a method using ultra high performance liquid chromatography coupled with quadrupole time‐of‐flight tandem mass spectrometry was established for the detection and identification of the metabolites in human and rat urine after oral administration of Xiao‐Qing‐Long‐Tang. A total of 19 compounds were detected or tentatively identified in human urine samples, including eight prototypes and 11 metabolites. Also, a total of 50 compounds were detected or tentatively identified in rat urine samples, including 15 prototypes and 35 metabolites detected with either a highly sensitive extracted ion chromatogram method or the MS^E determination using Mass Fragment software. Our results indicated that phase Ⅱ reactions (e.g. glucuronidation and sulfation) were the main metabolic pathways of flavones, while phase I reactions (e.g. demethylation and hydroxylation) were the major metabolic reaction for alkaloids, lignans, and ginger essential oil. This investigation provided important structural information on the metabolism of Xiao‐Qing‐Long‐Tang and provided evidence to obtain a more comprehensive metabolic profile.     

Investigation of the continuous flow of the sample solution on the performance of electromembrane extraction: Comparison with conventional procedure

In this study, electromembrane extraction from a flowing sample solution, termed as continuous‐flow electromembrane extraction, was developed and compared with conventional procedures for the determination of four basic drugs in real samples. Experimental parameters affecting the extraction efficiency were further studied and optimized. Under optimum conditions, linearity of continuous‐flow procedure was within 8.0–500 ng/mL, while it was wider for conventional procedures (2.0–500 ng/mL). Moreover, repeatability (percentage relative standard deviation) was found to range between 5.6 and 10.4% (n  = 3) for the continuous‐flow procedure, with a better repeatability than that of conventional procedures (2.3–5.5% (n  = 3)). Also, for the continuous‐flow procedure, the estimated detection limit (signal‐to‐noise ratio = 3) was less than 2.4 ng/mL and extraction recoveries were within 8–10%, while the corresponding figures for conventional procedures were less than 0.6 ng/mL and 42–60%, respectively. Thus, the results showed that both continuous flow and conventional procedures were applicable for the extraction of model compounds. However, the conventional procedure was more convenient to use, and thus it was applied to determine sample drugs in real urine and wastewater samples.     

Analysis of the human urine endogenous peptides by nanoparticle extraction and mass spectrometry identification

Peptides in urine are excreted by kidney from the blood and tissues, which are composed of a large amount of hormones, cytokines, regulatory factors and the metabolized fragments of proteins. The peptide distribution in urine will reflect the physiological and pathophysiological processes in body. In past, limited information was reported about the composition of the peptides in urine. One possible reason is that the peptides in urine are fairly low abundant and there are high concentrations of salts and organic metabolites in the urine. In this report, we extracted the peptides from human urine by highly ordered mesoporous silica particles with the pore size of 2 nm, which will exclude the high molecular weight proteins over 12 kDa. The extracted peptides were then separated into fractions according to their molecular weight by size exclusion chromatography. Each of the fractions was further analyzed by MALDI-TOF MS and μRPLC–MS/MS. Totally, 193 peptides were identified by two-dimensional SEC/μRPLC–MS/MS analysis. By analyzing the progenitor protein of the peptides; we found that two-thirds of the proteins differed from the reported urine proteome database, and the high abundant proteins in urine proteome were less detected in the urine peptidome. The developed extraction and separation methods were efficient for the profiling of the endogenous peptides in human urine. The peptidome in human urine was complementary to the human urinary proteome and may provide an emerging field for biomarker discovery.     

HPLC法测定人尿中尿酸含量

建立了一种人体尿液中尿酸含量的高效液相色谱测定方法.采用ACE5 AQ亲水色谱柱,pH3.2的乙酸水溶液为流动相,检测波长280nm.尿酸含量在7.1～224.6μg/mL范围内线性关系良好,平均加样回收率为99.7%～100.5%,RSD小于1.4%.将该法用于健康人和肝硬化病人尿液样本的测定,两类样本中尿酸含量无显...     

超高效液相色谱-串联质谱法测定人尿液中全氟有机化合物

采用超高效液相色谱-串联质谱(UPLC-MS/MS)联用技术,建立了对人尿液中12种全氟有机化合物(PFCs)的分析方法。首先在尿液样品中加入相应的同位素内标,以2%(体积分数)甲酸甲醇溶液超声萃取、离心后,将提取液用弱阴离子交换固相萃取柱净化,采用UPLC-MS/MS测定,内标法定量。12种目标化合物在0.05～50 μg/L质量浓度范围内线性良好,相关系数(r)均大于0.992,检出限在0.44～3.47 ng/L之间。在20、100、500 ng/L添加水平下,平均回收率范围为80.3%～116.2%,相对标准偏差(n=6)在5.5%～13.8%之间。该方法灵敏度高、重现性好、回收率高、操作简单,适合人尿液中PFCs的测定。     

暴露于环境烟气中的大鼠尿样代谢物分析

4-(甲基亚硝胺基)-1-(3-吡啶基)-1-丁醇(NNAL)是烟草特有亚硝胺4-(甲基亚硝胺基)-1-(3-吡啶)-1-丁酮(NNK)在生物体内的一种代谢标记物,分析暴露于烟气中的生物体内NNAL的含量是研究卷烟烟气对生物体健康影响的有效手段.基于人体的个体差异性很大,本文以饲养的大鼠为研究对象,采用LC-MS/MS...     

Some Observations on the Spectrophotometry Determination of Di-And Trihydric Phenols by Edta Titration

Abstract

Novel reaction between trioxalatoferrate (III) complex (A) and some di- and trihydric phenols were studied and found to form interesting mixed ligand chelates of iron (III) in the ratio 1:2:1 (Fe : oxalate : phenol) forming blue to violet colors at pH 4.0 to 6.5 and λ_max = 580 to 590 nm. These reactions were used for indirect volumetric and spectrophotometric microdetermination of catechol (PC), pyrogallol (PG), dopamine hydrochloride (DHCl), adrenaline hydrogen tartrate (AHT) and sulbutamol sulfate (SS) via EDTA titration using complex (A) as an indicator. PC, DHC1 and PG were determined by EDTA titration within the concentration ranges of 0.55-2.2, 0.95-3.79 and 0.65-2.52 μg ml^?1, respectively. AHT was determined in the concentration range of 96 to 204 μg ml^?1 and SS was also determined in the range 5.75 to 57.7 μg ml^?1. Adrenaline in ampoules coming from two Egyptian companies: sulbutamol in sulbovent liquids, and dopamine in five urine samples of Egyptian tumor patients, was also determined using the suggested procedure with high accuracy.     

Flow injection preconcentration by chemofiltration and spectrophotometric determination of Gd

A new on-line Gd preconcentration and determination system associated to flow injection (FI) method was developed. 2,2′-(1,8-dihydroxy-3,6-disulfonaphthylene-2,7-bisazo) bisbenzenearsonic acid (Arsenazo III) was used as a complexing agent at pH 2.5. A reactor containing the polyamide membrane was used for the retention of the Gd complex by chemofiltration. The complex was then removed from the reactor with buffer solution pH 9. The variables affecting the combined on-line preconcentration-absorptiometric method have been evaluated and optimised. The coupling of the on-line preconcentration and spectrophotometric flow through detection led to a detection limit of 15 μg l⁻¹ for a preconcentration time of 5 min at 2 ml/min. The method was successfully applied to biological samples.