Development and validation of high-performance liquid chromatography method for analysis of β-CCT and its related substances

Compound 2β-carbomethoxy-3β-(4-chlorophenyl)tropane (β-CCT) is a key intermediate for the synthesis of some clinical dopamine transporter (DAT) imaging agents. Potential impurities from synthesis process of β-CCT and degradation during storage might have detrimental effect on the final imaging agents. Thus, it is necessary to guarantee the quality of β-CCT. In this study, a rapid, sensitive and accurate high-performance liquid chromatography (HPLC) method was developed and validated for the analysis of β-CCT and its related substances. The chromatographic separation was achieved on a reverse-phase phenomenex? Gemini C18 column with an isocratic mobile phase consisted of methanol, water and TFA (30:70:0.1 v/v/v). The flow rate was 1.0 mL/min at 30 °C and samples were monitored at 220 nm. The method was validated concerning system suitability, linearity, accuracy, precision, specificity, robustness and stability. The limit of detection (LOD) and the limit of quantification (LOQ) of β-CCT were 0.5 and 1.5 μg/mL, respectively. The linearity range of β-CCT was 1.5–450 μg/mL with a good linear correlation coefficient (R² = 0.9999) between the peak response and concentration. Specificity investigation through forced degradation experiments displayed that β-CCT was stable in acidic, thermal and photolytic degradation conditions, but significantly unstable in alkaline and oxidative conditions. With the developed chromatographic method, possible impurity α-CCT from synthetic process and potential degradation products could be well separated from β-CCT. Good recovery and precision were manifested in the assay method. These results indicated that the present method would be suitable for not only the quality assurance of β-CCT in regular production sample assays but also the monitoring and determination of its related substances.     

Analysis of aquatic‐phase natural organic matter by optimized LDI‐MS method

The composition and physiochemical properties of aquatic‐phase natural organic matter (NOM) are most important problems for both environmental studies and water industry. Laser desorption/ionization (LDI) mass spectrometry facilitated successful examinations of NOM, as humic and fulvic acids in NOM are readily ionized by the nitrogen laser. In this study, hydrophobic NOMs (HPO NOMs) from river, reservoir and waste water were characterized by this technique. The effect of analytical variables like concentration, solvent composition and laser energy was investigated. The exact masses of small molecular NOM moieties in the range of 200–1200 m/z were determined in reflectron mode. In addition, spectra of post‐source‐decay experiments in this range showed that some compounds from different natural NOMs had the same fragmental ions. In the large mass range of 1200–15 000 Da, macromolecules and their aggregates were found in HPO NOMs from natural waters. Highly humic HPO exhibited mass peaks larger than 8000 Da. On the other hand, the waste water and reservoir water mainly had relatively smaller molecules of about 2000 Da. The LDI‐MS measurements indicated that highly humic river waters were able to form large aggregates and membrane foulants, while the HPO NOMs from waste water and reservoir water were unlikely to form large aggregates. Copyright © 2014 John Wiley & Sons, Ltd.     

反相高效液相色谱二极管阵列检测器对戊四硝酯粉质量的研究

建立了戊四硝酯粉含量及有关物质的RP-HPLC测定法。采用ODS色谱柱,甲醇/水(70∶30)为流动相,使戊四硝酯与有关物质基线分离,二极管阵列检测器检测波长206nm。本方法操作简便,重现性好。     

离子对反相高效液相色谱法分离伊班膦酸钠及其有关物质

采用离子对反相高效液相色谱法研究了伊班膦酸钠及其有关物质的色谱分离方法。以Inertsil C8色谱柱为固定相,乙腈．甲醇．12mmol／L乙酸铵缓冲液（含35mmol／L正戊胺,pH7．0）（8：4：88）为流动相,流速为1．0mL／min,分析物以通用型的蒸发光散射检测器（ELSD）测定。在该色谱条件下,伊班膦酸钠及其有关物质分离良好且能够被同时检测。本方法采用的可挥发离子对试剂和缓冲液的流动相系统,同时解决了伊班膦酸钠及其有关物质的分离与检测的问题,简单快速、专属性强,适用于伊班膦酸钠的有关物质检测,为该药的质量控制提供了简便可靠的分析手段。     

酸枣果肉中挥发性化学成分的提取及分析

报道了用蒸馏-萃取法和同时蒸馏-萃取法提取酸枣果肉中挥发性物质,测得两种方法提取的酸枣果肉挥发油含量分别为1．80％和2．30％。用GC／MS法从酸枣果肉挥发油中分别分离并确定出43种和28种化学成分,分别占酸枣果肉挥发油总检出量的95．62％和94．88％。用峰面积归一化法通过化学工作站数据处理系统,得出各化学成分在挥发油中的相对百分含量。     

氟甲砜霉素注射液含量及其有关物质的HPLC测定

为建立测定氟甲砜霉素注射液含量的方法,采用高效液相色谱法,选用Agilent EclipseXDB-C8柱(4.6 mm×250 mm,5μm),Lab Alliance C8保护柱(4.6 mm×10 mm,5μm),流动相为(V乙腈) V(水)=35 65,流量1.0 mL.min-1,检测波长224 nm,进量样20μL,柱温为室温。结果表明,方法的线性范围为10.0～400μg.mL-1(r=0.999 6),最低检测限2.0 ng。回收率98.7%～101.2%,RSD 0.30%～1.22%(n=5)。方法简便灵敏,结果准确可靠,可用于氟甲砜霉素注射液的质量控制。     

我国典型电子垃圾拆解地持久性有毒化学污染物污染现状

电子垃圾拆解所引起的环境问题已经受到广泛关注,根据联合国环境规划署统计,全球约70%的电子垃圾通过各种途径进入我国,而我国自身也产生大量的电子垃圾。我国电子垃圾拆解活动采用的工艺较为原始,位于广东的贵屿和浙江的台州是我国最大的两个电子垃圾拆解地,拆解过程中电子垃圾本身含有和不当处置所产生的大量持久性有毒化学污染物(如重金属、二 NFDA1 英类、溴代阻燃剂等)释放到环境中,对拆解地生态系统及居民健康造成严重的威胁。本文重点针对我国电子垃圾拆解所造成的持久性有毒污染物(PTS)污染现状、管理措施和法规、拆解区居民所面临的持久性有毒污染物暴露健康风险及其相关研究最新进展进行了分析和概括,并对电子垃圾拆解区域持久性有毒污染物及新型环境污染物研究和发展方向作了展望。     

A Multicolumn Ion Chromatographic Determination of Nitrate and Sulfate in Waters Containing Humic Substances

Abstract

A three-column ion chromatographic system for the removal of humic substances from natural waters, and subsequent on-line concentration and determination of nitrate and sulfate using non-suppressed ion chromatography is presented. Humic substances are removed using disposable adsorption columns packed with chemically bonded amine silica material. The sample is directly transfered to an ion exchange column where the anions are concentrated ca 10 times. After reversing the flow, the ions are transferred to a third column where they are separated and quantified. The detection limit is less than 1 mg L^?1 of nitrate or sulfate in water containing 45mgL^?1 of humic acid.     

3类高关注紫外线吸收剂的前处理与检测技术研究进展

紫外线吸收剂是一种具有强烈吸收紫外线作用的光稳定剂,会对生态环境以及人体健康造成危害,国内外许多国家已制定相关法规限制其使用。该文综述了近几年来国内外关于二苯甲酮类、三嗪类和苯并三唑类3类紫外线吸收剂检测的研究现状,分别对样品前处理与检测技术进行了详细介绍,并对其研究发展趋势进行了展望。     

基于甲基苯丙胺和吗啡的胶体金免疫层析试剂盒检测法的可靠性评价

通过固相萃取-液相色谱-多级质谱(SPE-LC-MS/MS)联用技术和毒品胶体金免疫层析试剂盒检测法对13种中药及调味品样品中甲基苯丙胺及吗啡分别进行定量分析,依据LC-MS/MS检测结果,对毒品胶体金免疫层析试剂盒检测法进行可靠性评价。实验结果表明:型号1试剂盒对甲基苯丙胺和吗啡的特异性均不高,检测准确率分别为57.7%与78.8%;型号2试剂盒对甲基苯丙胺的特异性不足,准确率为73.1%,但对吗啡的检测准确率达到100%。在利用毒品胶体金免疫层析试剂盒进行毒品快速筛查时,应注重排除干扰因素以提高免疫胶体金层析试剂盒的检测准确度。