微分电位溶出法测定尿中铅

作者研究了用微分电位溶出法测定尿中铅。尿样用盐酸酸化至0.2mol/L,直接用预镀汞膜的玻碳工作电极在-1.2V(对SCE)富集80秒,用标准加入法定量。结果:铅的线性范围在0～150ppb,检出限达2ppb,尿样中铅的回收率达89.5～110.0％,相对标准偏差为1.6％。本法灵敏、快速、准确、简便,而且成本低廉,样本不需消化处理,不使用有机溶剂等有毒物质;与双硫腙法比较,其结果无显著性差异。     

溶出伏安法直接测定尿铜的研究

溶出伏安法测定尿铜需将尿样先消化，本文改用盐酸酸化后加入Tritonx-100等底液，即可用溶出伏安法测尿铜。本法检出下限为2.5pp^b，变异系数4.54-6.45%，回收率82．35％－108．33％，铜含量在10－100pp^b与溶出电流峰有良好的线性关系。本法分别与尿样消化后再测定和原子吸收光谱法比较，差异均无显著性意义（P＞0．05），亦密切相关（P＞0．05）。本法快速，简单，实用。     

钯作为基体改进剂在石墨炉原子吸收光谱法测定尿铅中的应用

目的：探讨钯作为基体改进剂在石墨炉原子吸收光谱法测定尿铅中的应用价值。方法：用氯化钯作为基体改进剂,配制标准曲线,然后对非铅接触组和铅接触组尿液测定,用同法对尿铅标样进行测定,观察其相对误差。结果：标准1（尿比重≤1．016）的标准曲线为Y=0．746X＋0．04816（r=0．9999）;标准2（尿比重1．016～1．028）为Y=0．988X-0．03418（r=-0．9999）;标准3（尿比重〉1．028）为Y=O．948X＋0．05346（r=0．9999）;三个标准曲线铅的最低检出浓度均为2．0μg／L。精密度实验中,平均浓度为（26．75±1．19）μg／L、（73．24±1．33）μg／L的两尿样,RSD分别为5．27％、3．47％。准确度试验中,浓度为30．26、50．26、70．26μg／L的加标尿样测得的回收率分别为102．28％、98．55％、97．62％。用该法测定尿铅标样ZK103—1（82．00μg／L）、ZK103—2（221．00μg／L）相对误差分别为1．70％、1．41％。用该法均可测定正常人及铅接触人群的尿铅浓度。结论：石墨炉原子吸收光谱法应用基体改进剂测定尿铅速度快,准确度、灵敏度高,结果可靠。     

Development and validation of LCMS method for determination of Ethyl Glucuronide (EtG) in urine

BackgroundEthyl glucuronide (EtG) is a phase II metabolite of ethanol and is an upcoming biomarker for recent alcohol intake. Monitoring of alcohol intake in case of alcohol-dependent syndrome is very useful for early intervention and preventing harmful effects. EtG has also been identified as a very useful marker in differentiating antemortem ingestion of alcohol from postmortem production of alcohol. This study was undertaken with an objective of developing a sensitive and specific method for determination of EtG in urine.MethodsTriple quadruple Liquid Chromatography (LC)-Mass Spectrometry (MS) with Electrospray Ionization (ESI) negative mode has been used for developing the multiple reaction monitoring method by using the Polaris 3 C 18-Ether analytical column. A simple sample preparation method was adopted using the Bond Elute Plexa PAX SPE cartridge. The developed method was also tested on actual urine samples from 15 individuals after consumption of 60 and 90 ml of whiskey at different time intervals.ResultsA simple method was developed for determination of EtG in urine, with a sensitivity of 100 ppb and a recovery of 75%. Validation of the method on urine samples revealed that EtG could be detected for up to 18 h in individuals who ingested 60 ml of whiskey and up to 24 h in those who ingested 90 ml of whiskey.ConclusionThe simple method was developed for determination of EtG in urine and validated on actual urine samples. This method can now be used in aircraft accident investigation to differentiate postmortem production of alcohol, and the method is also a very useful tool to monitor Alcohol dependent Syndrome (ADS) cases.     

微波消解——氢化物原子荧光光谱法测定食品中铅

目的研究氢化物原子荧光光谱法测定食品中铅。方法采用微波消解作食品样品前处理方法，用氢化物发生原子荧光光谱法检测食品中铅。结果铅的．测定线性范围为0～80ng／ml，方法的相对标准偏差为2．32％，回收率为92．0％～102．O％。结论氢化物原子荧光光谱法准确，干扰物质少，与石墨炉原子吸收光谱法测定结果相一致。     

Antibody-coated bacteria in the urine of preschool and school-aged girls with asymptomatic bacteriuria.

Urine samples from 3564 girls aged 2 to 13 years were screened for evidence of infection. Cultures were positive (bacteria count, more than 10(5)/ml) in 61 (1.7%) by the dipslide method and in 55 (1.5%) by standard culture techniques. In 13 (23.6%) of the 55, antibody-coated bacteria (ACB) were detected in the urine. The clinical, bacteriologic, radiologic and urinalysis findings in children with ACB were no different from those in children in whom the bacteria were not coated. Direct examination of uncentrifuged urine under high power revealed one or more bacteria per two high-power fields in 96% of infected urine samples and in only 7% of noninfected samples. Five or more leukocytes per high-power field in centrifuged urine were detected in 36.7% of infected urine samples but not in noninfected samples. The ACB test did not differentiate between asymptomatic bacteriuria with parenchymal scarring or vesicoureteral reflux or both and asymptomatic bacteriuria without these abnormalities.     

RP-HPLC-ECD检测血浆尿液中儿茶酚胺及其临床应用

目的 建立一种简便、准确、灵敏、易于临床推广的测定血尿中儿茶酚胺(CAs，包括NE、E、DA)的检测方法，并进行了临床血浆及24小时尿液标本中CAs测定。方法 采用活性氧化铝吸附标本中CAs，酸解吸附后，以3，4-二羟基苄胺(13HBA)为内标，利用离子对反相高效液相色谱及电化学检测器进行测定。结果 显示NE、E、DA在0．156—100ng／ml浓度范围内与响应值(色谱峰面积对内标峰面积之比)线性关系良好(r分别为0．9998、0．9999、0．9998)，其方法回收率分别为63．2％—93．4％、65．6％—103．7％、70．4％—111．3％，CV值为1．23％—19．52％，在嗜铬细胞瘤患者中CAs有显著升高。结论 该实验方法简单、准确、灵敏、特异性高，不失为一种敏感、可靠的诊断嗜铬细胞瘤的方法。     

高效液相色谱法测定尿中苯妥英代谢物浓度

A high-performance liquid chromatographic method for the determination of p-hydroxyphenytoin (p-HDPH) in human urine was reported. Following acid hydrolysis of urine sample at 90 degrees C for 1 h, an internal standard, nitrophenol, was added. The sample was extracted with n-hexane-ethyl acetate (50:50), and organic layer was evaporated. The residue was dissolved in methanol and chromatographed on an Ultrasphere-ODS column, using a mobile phase of phosphate buffer (0.03 mol/L, pH 6.0): methanol (65:35) at a flow rate of 0.8 ml/min. The eluent was monitored at 240 nm. The standard curve was linear within the range 5.0-200 micrograms/ml (r = 0.9998). Analytical recovery rates were 102.8 +/- 7.3% (p-HDPH 9.70 micrograms/ml, n = 5) and 104.9 +/- 6.4% (p-HDPH 54.70 micrograms/ml, n = 5). The cumulative recovery of p-HDPH in 0-12 h volunteers' urine samples accounted for 20% of the oral dose of 100 mg phenytoin sodium.     

石墨炉原子吸收法测定尿铬的实验条件探讨

目的对石墨炉原子吸收法测定尿铬的实验条件进行探讨,并确定方法最佳试验条件,以改善并提高本方法的灵敏度和准确度。方法优化石墨炉在测定尿铬的升温程序,确定最佳样品保存酸度和保存时间,应用硝酸铵基体改进剂改善背景干扰,比较并确定合适的线性范围,对实际样品进行加标回收率和精密度测定。结果对石墨炉测定尿铬的升温程序进行优化后提高了测定方法的灵敏度,确定使用1%的硝酸作为样品的保存酸度,加入10μL30%的硝酸铵基体改进剂,经比较后确定0～10μg/L铬工作曲线作为最佳线性范围。对54份尿样进行测定,样品均值加标回收率为97%~110%,精密度均值为3.57%~7.89%。结论应用石墨炉原子吸收法测定尿铬,对实验条件进行探讨后,确定样品最佳保存酸度和保存时间,通过优化石墨炉升温程序并加入硝酸铵基体改进剂,确定0～10μg/L铬线性范围后,方法更可靠,灵敏度更高,     

柱前紫外衍生-高效液相色谱法测定全氟辛酸

目的 建立污水和尿液中全氟辛酸(PFOA)的柱前紫外衍生-高效液相色谱测定方法.方法 样品中的PFOA与四丁基氢氧化铵形成的离子缔合物被甲基叔丁基醚萃取后,与ω-溴苯乙酮在乙腈中衍生成具有紫外吸收的物质,高效液相色谱-紫外可见检测器检测.结果 方法检出限可达7.0 μg/L;相对标准偏差(RSD) ＜10%;样品的回收率在85.3%～116%之间.结论 本法适用于测定水样及尿液中的全氟辛酸.