人尿中硒脲存在的实验验证

已知人尿中的硒主要以三甲基硒离子形式存在,国内外至今还没有人证实人尿中存在硒脲。本文设计了一种检验方法,称富集-化学分离-三氟乙酰酐衍生气相色谱法,首次证实人尿中硒脲的存在。此发现对阐明硒在人体中的代谢历程有重要意义。     

新生儿及其乳母碘营养状况探讨

为了解杭州部分地区现行加碘盐含量是否满足孕妇分娩时碘营养需求,采用碘铈催化分光光度法对79对新生儿及其母亲尿碘进行了检测。结果表明,新生儿组尿碘明显高于其母亲组(t=22.62,P<0.01)。新生儿的尿碘与其母亲尿碘含量呈正相关(r=0.862,P<0.01),母亲组尿碘小于100μg/L,有9人,占本组11.4%。新生儿组有10人及其母亲组有57人,尿碘在100~200μg/L,分别占本组的12.7%和72.2%。表明母亲组碘营养轻度不足比例较高。     

大骨节病活跃严重病区和邻近非病区儿童尿硒与尿羟脯氨酸关系研究

通过测定尿硒、尿羟脯氨酸含量,研究了大骨节病活跃严重病区和邻近非病区儿童尿硒含量和尿羟脯氨酸含量的变化及其相关性.结果表明,大骨节病活跃严重病区组儿童尿硒含量和尿羟脯氨酸含量均明显低于邻近非病区组（P＜0.01）,处于病区中较低水平.两组的尿硒含量与尿羟脯氨酸含量均显著正相关（r=0.582,P＜0.01;r=0.383,P＜0.05）.这些结果提示,体硒水平是影响尿羟脯氨酸排泄量的原因之一,大骨节病活跃严重病区儿童的低硒状态,是导致其尿羟脯氨酸减少的一个重要因素.     

毛细管电泳-电化学发光法研究阿莫西林在人尿中的药代动力学

建立了毛细管电泳一电化学发光(CE-ECL)法测定人尿中阿莫西林的新方法,并将该方法用于人尿中阿莫西林药代动力学的研究.结果表明:阿莫西林在尿液中平均回收率为95.35%,该方法的线性范围为0.001～5.0μg/mL,检出限(3σ)为0.32ng/mL,对1.0μg/mL阿莫西林连续测定6次,其相对标准偏差小于2.0%.给药后6 h内的排泄率为44.54%,人尿中阿莫西林最大药物浓度出现时间为1.0～1.5 h.本方法用于人尿中阿莫西林药代动力学的研究具有快速、简便、灵敏、样品用量少等特点.     

煤烘玉米和饮水为介质地氟病区骨畸形病人全血尿多元素含量的分析

采集了贵族个煤烘玉米为主要介质和河北２个饮水为介质氟病区内骨畸形病人的全血、尿、检测了其中８种元素含量,结果表明,贵州各氟病区少儿骨软化与成年骨硬化畸形病人的全血铝、钙、磷、铁和尿氟、铝均显著高于同龄对照组,尿磷均低于同龄对照组。少儿骨软化病人全血锌均下降,尿锌多下降。某水型氟病区骨软化经产妇尿氟、全血铜升高;骨软化少年全血铝显著升高,锌、铁下降,尿氟升高,尿锌,磷下降。海边的典型氟骨症病人全血、     

孝感地区初诊甲状腺疾病患者尿碘水平分析

目的通过对孝感地区初诊甲状腺疾病患者的尿碘水平的检测,探讨尿碘水平与甲状腺疾病发生的相关性。方法选择孝感地区160例初诊甲状腺疾病患者作为观察组,同期选择60例健康体检者作为对照组,两组均采用砷铈催化分光光度计法测定尿碘含量,同时采用免疫化学发光法测定血甲状腺功能(FT3、FT4、TSH)及甲状腺抗体(TGAb、TMAb)水平,完善两组人群甲状腺彩色超声检查。结果 1两组尿碘中位数均100μg/L。2观察组尿碘中位数及平均值均明显高于对照组。3观察组中尿碘中位数及平均值均存在由高到低的以下规律:功能亢进组,功能正常组,功能减低组,显示尿碘越高,甲状腺功能水平越高。4观察组随着尿碘水平的增加,甲状腺体积逐渐增大(取肿大明显的单侧比较),但TGAb、TMAb组间比较无统计学差异。结论尿碘水平的升高是导致初诊甲状腺疾病患者甲状腺功能和形态改变的原因,其与甲状腺自身抗体无明显相关性。孝感地区人群食用普通碘盐后尿碘水平部分过量,需提倡科学补碘。     

高效毛细管区带电泳测定人尿液中尿酸、肌酐和伪尿核苷的含量

报道了采用高效毛细管区带电泳技术直接将人尿液注入毛细管进行尿液中肌酐、尿酸及伪尿核苷含量测定的新方法。试验表明,以磷酸盐（ｐＨ６．１）作缓冲液,对人体尿液中肌酐、尿酸及伪尿核苷进行直接分析具有较高的灵敏度和较好的重复性。     

尿中微量芳香酸的高效毛细管电泳分析--用于苯丙酮酸尿症的诊断

建立了可用于诊断苯丙酮酸尿症的5种尿中微量芳香酸的毛细管电泳分析新方法.应用硼砂-胆酸钠(均为25mmol/L,pH=10.0)电泳介质体系,可将5种芳香酸在15min内达到全分离;最低检测限达1.5×10-9mol;采用Sep-PakC18微柱进行尿样前处理,有效地除去了尿蛋白对分离的干扰,可作为苯丙酮酸尿症的筛查方法.     

用GC—MS法测定尿中可待因及其代谢物的浓度

建立了用ＧＣ－ＭＳ（ＳＩＭ）内标定量法快速测定人尿中可待因及其代谢物浓度的方法，样品经酸水解、乙醚／异丙醇提取，用ＭＳＴＦＡ－ＭＢＴＦＡ衍生化后进样于ＧＣ－ＭＳＤ，方法灵敏、准确，可用于监测吸毒者尿中可待因，吗啡类药物的浓度。本法已经受ＩＯＣ的１９９２年水平考试的考验。     

尿中有机酸的毛细管气相色谱—质谱轮廓分析—用于苯丙酮尿症的诊断

应用毛细管气相色谱-质谱轮廓分析方法,测定了33例2.5～4.5岁健康儿童尿中有机酸种类及含量和8例拟诊为苯丙酮尿症儿童尿中的有机酸,结果表明患儿尿样中苯丙酮酸、苯乙酸、邻羟基苯乙酸、对羟基苯乙酸高于正常值10～470倍。为苯丙酮尿症的确诊提供了可靠方法。     

Determination of remoxipride in human plasma and urine by reversed-phase ion-pair high-performance liquid chromatography.

A sensitive method is described for the measurement of remoxipride in human plasma and urine. Remoxipride and its internal standard are extracted from plasma or urine at pH 12 with a mixture of hexane and methyl tert.-butyl ether. After washing the organic phase with base, the compounds are extracted into acid and analyzed on a C18 column with ultraviolet detection at 214 nm. The mobile phase is composed of acetonitrile and aqueous buffer (sodium perchlorate and phosphoric acid, pH 1.7). The limits of reliable quantitation for remoxipride are 12.5 and 50 ng/ml for plasma and urine, respectively. The run times are 6 min for plasma and 3 min for urine. The method has been successfully used to assay remoxipride clinical study samples. This mobile phase has also been successfully applied to the analysis of other basic drugs such as cimetidine, codeine, diltiazem and quinidine with minor modifications.     

Separation and determination of 11 marker pteridines in human urine by liquid chromatography and fluorimetric detection

A simple liquid chromatographic method has been developed to achieve the complete separation and determination of a wide range of pteridinic compounds and creatinine (CREA) in urine samples, in just one run. The influences of mobile phase composition and buffer pH have been studied. The optimized mobile phase was composed of a Tris-HCl buffer (15 mmol/L) at pH 6.10 solution (eluent A) and a Tris-HCl buffer (15 mmol/L) at pH 6.40 solution (eluent B), in gradient mode. Analytes were determined by fluorimetric detection, exciting at 272 nm, and measuring the fluorescence emission at three wavelengths, 410, 445 and 465 nm. CREA, as a reference of metabolites excretion in urine, was determined by photometric detection at 230 nm. Pteridines detection limits varied from 0.2 to 6.1 ng/mL, and 0.2 g/mL for CREA. Calculated precision values expressed as RSD (%) varied from 1.1 to 5.9. Two different oxidation procedures for urine samples were optimized. The neopterin/biopterin ratios found were 0.98 and 0.86 for adults and children, respectively, by means of the alkaline iodide/iodine oxidation and 0.45 and 0.57 using neutral KMnO(4) oxidation.     

High-performance liquid chromatographic determination of glibenclamide in human plasma and urine

A selective and sensitive high-performance liquid chromatographic method for determination of intact glibenclamide in human plasma or urine has been developed. With glibornuride as internal standard, acid-buffered plasma or urine was extracted with benzene. The organic layer was evaporated and the residue was dissolved in equilibrated mobile phase (acetonitrile-phosphate buffer 0.01 M pH 3.5, 50:50). An aliquot of 20 microliters was chromatographed on a Spherisorb ODS reversed-phase column, and quantitation was achieved by monitoring the ultraviolet absorbance at 225 nm. The response was linear (0-1000 ng/ml) and the detection limit was 5-10 ng/ml in plasma or urine. The within-assay variation was less than or equal to 10%. No interferences from metabolites or endogenous constituents could be noted. The utility of the method was demonstrated by analysing glibenclamide in samples from diabetic subjects on therapeutic doses of the drug.     

Determination of luxabendazole in biological fluids by high-performance liquid chromatography.

Luxabendazole, a new benzimidazole, is a highly potent broad-spectrum anthelmintic. A high-performance liquid chromatographic method has been developed for its determination in serum and urine samples. In order to optimize the clean-up of samples we compared two procedures: C18 Sep-Pak cartridges and ultrafiltration through a cellulose membrane with a 30,000 relative molecular mass cut-off. In order to obtain the most suitable mobile phase, we studied the influence of pH and acetonitrile content on the capacity factor (k'). Chromatographic separation and quantification were performed on a reversed-phase column packed with 5-microns Nucleosil C18. The mobile phase was acetonitrile-0.05 M phosphate buffer (pH 7.0), (40:60, v/v). The column effluent was monitored by ultraviolet-visible spectrophotometry at 290 nm. The method shows good recovery, precision and accuracy. The lower limit of detection for luxabendazole is 15 ng/ml in serum samples and 25 ng/ml in urine samples.     

Direct Urine Injection with Micellar Liquid Chromatography-Amperometric Detection for Dopamine Monitoring

Abstract

Micellar liquid chromatography with amperometric detection was evaluated for the determination of dopamine in urine. The samples were injected directly without time-consuming protein precipitation. The separations were carried out in an analytical column packed with C18. The mobile phase was 0. 01M SDS with 3% n-propanol added at pH 4. 15. The limit of detection for dopamine is 4 pg. Eight urine samples were analyzed. The results were in a reasonable range.     

Determination of vanilmandelic acid in urine by coupled-column liquid chromatography combining affinity to boronate and separation by anion exchange

An automated liquid chromatographic method for assaying vanilmandelic acid in urine is described. Vanilmandelic acid and potential interfering substances, such as catechol compounds and their metabolites, have been tested for affinity to boronic acid-substituted silica at various pH values. Vanilmandelic acid and the internal standard, isovanilmandelic acid, were bound to the boronate matrix at an acidic pH, whereas for instance catecholamines were unretained and passed through the column. The alpha-hydroxycarboxylic acids were then desorbed by another mobile phase (pH 6.0) and transferred to an anion exchanger for chromatography and electrochemical detection. A relative standard deviation of 2.8% was obtained for the analysis of human urine samples containing 6.6 microM vanilmandelic acid.     

High-performance liquid chromatographic determination of glipizide in human plasma and urine

A sensitive and selective high-performance liquid chromatographic method for determination of intact glipizide in human plasma or urine has been developed. The plasma and urine samples were acid-buffered, before tolbutamide was added as internal standard. The samples were extracted with benzene, and the organic layer was evaporated to dryness. The residue was dissolved in equilibrated mobile phase (acetonitrile-0.01 M phosphate buffer pH 3.5, 35:65), and an aliquot of 20 microliters was chromatographed on a Spherisorb ODS reversed-phase column. Quantitation was achieved by monitoring the ultraviolet absorbance at 275 nm. The response was linear (0-1000 ng/ml) and the detection limit was 5-10 ng/ml in plasma or urine. The within-assay variation was less than or equal to 10%. No interferences from metabolites or endogenous constituents were observed. The utility of the assay was demonstrated by determining glipizide in samples from a diabetic subject receiving a therapeutic dose of 5 mg of the drug.     

Determination of clozapine and its metabolites in serum and urine by reversed phase HPLC

A rapid, specific and sensitive method using reversed phase HPLC for the simultaneous determination of clozapine and its two metabolites in serum and urine has been developed. The mobile phase was a mixture of 67% (v/v) methanol in water containing 0.4% tetramethylethylenediamine and 0.32% acetic acid (pH 5.5). The influence of methanol content, the pH of the mobile phase and the effect of adding alkylammonium ions as peak tailing reducer in the mobile phase have been investigated. The solvent for extracting clozapine from serum and urine was ether. 50 microliters of 0.25 M H2SO4 solution was used to redissolve the dry residue to eliminate the endogenous compounds which could otherwise be eluted together with clozapine from the HPLC column. The analysis of a single sample was accomplished within half an hour. The identities of the chromatographic peaks of clozapine and its N-demethyl metabolite collected from the patient urine sample were confirmed by mass spectrometry. The method is sufficiently sensitive (5 ng/ml) and reproducible (CV 2.9%-6.7%) for clinical and pharmacokinetic studies, and preliminary results in these respects are presented.     

色氨酸及其主要代谢产物的分离和在生物样品中的测定

建立以乙酸缓冲系统和甲醇作流动相、电化学和紫外检测器联用的高效液相色谱法,分离和测定了色氨酸经5-羟色胺和犬尿酸原两条主要代谢途径的8种代谢物。使用三氯乙酸作离子对试剂以延长3-羟犬尿酸原的保留时间,分析了流动相pH值和三氯乙酸浓度对各物质分离的影响及检测条件。结果表明,pH值及三氯乙酸浓度对各物质保留时间有明显影响,可作为控制分离的主要因素。此外,对生物样品中各物质分离和检测条件进行了讨论。     

Determination of ethyl glucuronide in urine using reversed-phase HPLC and pulsed electrochemical detection (Part II)

A direct, versatile method for the determination of ethyl glucuronide (EtG), a biomarker of ethanol consumption, in urine has been developed using reversed-phase liquid chromatography with pulsed electrochemical detection (PED). EtG and methyl glucuronide (MetG), which serves as an internal standard, are readily separated using a mobile phase consisting of 1% acetic acid/acetonitrile (98/2, v/v). Post-column addition of NaOH allows for the detection of all glucuronides using PED at a gold working electrode. Upon optimization, EtG was found to have a limit of detection of 0.03 μg/mL (7 pmol; 50 μL injection volume) and repeatability at the limit of quantitation of 1.7%R.S.D. (relative standard deviation). Solid-phase extraction (SPE) using an aminopropyl phase was used to remove interferents in urine samples prior to their analysis. Compound recovery following SPE was approximately 50 ± 2%. The forensic utility of this method was further validated by the analysis of 29 post-mortem urine specimens, whose results agreed strongly with certified determinations.