9-芴甲氧羰酰氯柱前衍生-高效毛细管电泳法测定人血浆中牛磺酸

建立了区带毛细管电泳法快速测定人血浆中牛磺酸的方法.血浆样品经乙腈沉淀蛋白并离心后,上清液中牛磺酸与9-芴甲氧羰酰氯在室温及pH 9.5条件下避光反应20 min,生成具有紫外吸收的衍生产物,以40 mmol/L的乙酸钠(pH 4.6)为运行缓冲溶液,熔融石英毛细管为分离柱;分离电压22kV;紫外检测.实验结果表明:在优化的实验条件下,样品检测仅需9 min,牛磺酸质量浓度在2.5~40.0 μg/mL范围内具良好线性关系(r=0.9995),检出限为0.8 mg/L(S/N=3),迁移时间和峰面积RSD分别为0.27%和1.8%,加标回收率90.3%～108.0%.用本法测定18名健康成人血浆中的牛磺酸,均值为15.8±3.2μg/mL.     

高效毛细管电泳法检测牛奶中的青霉素中间体以及3种青霉素类药物

建立了高效毛细管电泳(HPCE)同时检测牛奶中青霉素类抗生素中间体6-氨基青霉烷酸(6-APA)以及3种青霉素类药物青霉素钾(PEN)、氨苄青霉素(AMP)和阿莫西林(AMO)的方法。利用正交实验设计,对HPCE中的缓冲液离子浓度和pH值、分离电压、分离温度等分离条件进行了优化。结果表明: 在采用40 mmol/L磷酸二氢钾-20 mmol/L硼砂缓冲体系(pH 7.8)、分离电压为28 kV、分离温度为30 ℃的电泳条件下,4.5 min内可以实现上述4种青霉素类药物的快速分离检测。各组分在1.56～100 mg/L范围内有良好的线性,相关系数(r2)为0.9979～0.9998,加标回收率为84.91%～96.72%,相对标准偏差(RSDs)为1.11%～9.11% (n=6)。该方法简便、快速,可以应用于市售牛奶中4种青霉素类药物的快速检测。     

二元环糊精体系对柴胡中柴胡皂苷a与柴胡皂苷d的毛细管电泳分离测定

以磺丁基-B-环糊精(SBE-β-CD)和β-环糊精(β-CD)组成二元手性选择体系,用毛细管电泳法对柴胡中的柴胡皂苷a及柴胡皂苷d进行分离测定.考察了缓冲液的组成和浓度、手性选择剂的组成和浓度、进样方式及样品介质等对灵敏度和分离度的影响.结果表明:采用熔融石英毛细管柱(60 cm×50 μm i.d,有效长度为53 ...     

高效毛细管电泳I. 分析化学中的一个新的前沿领域

本文是关于高效毛细管电泳(HPCE)的详细综述的第一部分,概括了HPCE技术发展的历史、国内外研究现状,总结了HPCE的基本原理、主要操作方式以及HPCE所具有的特点,并讨论了该技术目前存在的问题及可能的解决方法。     

功能食品与饮品中牛磺酸的柱前衍生-高效毛细管电泳法快速测定

建立了功能食品和饮品中牛磺酸的高效毛细管电泳快速分析方法。以邻苯二甲醛(OPA)为衍生剂进行柱前衍生,采用45 mmol/L(pH9.5)的硼砂缓冲溶液为运行缓冲溶液,熔融石英毛细管(50 cm×50μm,有效长度41 cm,未涂层)为分离柱;柱上紫外检测波长:335 nm,分离电压19 kV,电泳温度20℃,重力进样,进样时间10 s。牛磺酸的质量浓度在5.0~100.0 mg/L范围内呈良好线性关系(r0.999),检出限(S/N=3)为1.6 mg/L,迁移时间和峰面积的相对标准偏差(n=7)分别为2.4%和3.8%。用该法测定了功能食品、乳制饮品和饮料等样品中的牛磺酸,相对标准偏差为0.7%~3.7%,加标回收率为93%~111%。     

改良聚酰胺吸附-高效毛细管电泳内标法测定饮料中的亮蓝和苋菜红

以日落黄为内标物,建立了碳酸饮料中亮蓝和苋菜红的高效毛细管电泳内标测定方法。毛细管有效长度40 cm,内径75 μm,分离电压20 kV,进样量14 kPa×3 s,室温下分离,缓冲溶液为10 mmol/L磷酸氢二钠(pH 8.56),检测波长390 nm。亮蓝与苋菜红的相对校正因子分别为0.8329(相对标准偏差(RSD)为3.3%)和1.2253(RSD为2.6%);定量限(S/N=10)分别为1.629 mg/L和4.160 mg/L;回收率分别为97.87%～102.1%(RSD为1.8%)和94.07%～103.8%(RSD为4.1%);方法的精密度分别为3.2%和2.0%。对样品预处理的优化使该法更适用于碳酸类饮料中亮蓝和苋菜红的高效毛细管电泳分析。以样品空白为基液进行内标法定量测定,基本上消除了背景带来的系统误差。将该方法应用于实际样品的测定,结果准确。     

小分子大豆多肽的分离检测研究

最近的研究表明,多肽特别是二肽和三肽更易被人体吸收,此外小分子大豆肽还具有很好溶解性、稳定性、低粘度和许多生理活性,如降血压,降胆固醇,抗疲劳等,因此大豆肽广泛应用在食品、化妆品、药品等领域 [1,2].     

A novel amphipathic block copolymer coating forming micelle-like aggregates for separation of steroids in open tubular capillary electrochromatography

A new amphipathic block copolymer, poly(tert-butyl acrylate)₁₂₇-block-poly(glycidyl methacrylate)₈₆, was developed for the coating in open tubular capillary electrochromatography. The self-assembly characters of the coating, which could form micelle-like aggregates under proper conditions, were observed by atomic force microscopy. Compared with bare capillary, this coating could act as surfactant and lead to improve the separation of steroids. In addition, the influence of pH, buffer concentration and organic solvents on the separation was investigated. The best separation of the three model steroid analytes could be achieved using 20.0 mM borate buffer at pH 10.5. For covalent bonding, the coating showed good repeatability and stability with RSD of u_EOF less than 3.3%. Then, this proposed method was well validated with good linearity (≥0.999), recovery (91.0-94.0%) and repeatability, and was successfully used for separation of steroids in spiked serum samples, which indicated that this new OT-CEC method could provide a potential tool to determine steroids in real biological system without interference.     

X-ray absorption fine structure of artificial antigens for cadmium

Immunoassay technology as a quick and large-scale screening method to detect metal ions in foods and environmental samples has rapidly been developed due to several advantages over conventional instrument-intensive methods. Unlike biomacromolecule, metal ions are haptens without immunogenicity, so successful preparation of artificial antigens is the first critical step for establishing immunoassay methods for them. In the current paper, cadmium ions were conjugated to BSA and OVA, respectively, using bifunctional chelator, p-SCN-Bn-DTPA. The ultraviolet analysis indicated that the maximum absorption peak of Cd–p-SCN-DTPA–BSA and Cd–p-SCN-DTPA–OVA had a small peak shift and an apparent absorbance increase compared to that of BSA and OVA, and the extents of substitution of ?-amino in both conjugates were 51.2% and 58.6%, respectively. In addition, the EXAFS of conjugates implied that Cd²⁺ coordinated with N and O atoms of DTPA in artificial antigens, the coordination type and number of Cd–DTPA, Cd–p-SCN-Bn-DTPA–BSA, Cd–p-SCN-Bn-DTPA–OVA were the same. XANES region and geometries of the three compounds were also same. These results implied that the three antigens had the similar local structure and atomic geometry.This was the first time that the XAFS was attempted for the identification of artificial heavy metal ion antigens.     

血中胺碘酮的胶束电动毛细管电泳优化分析

建立了血中胺碘酮的胶束电动毛细管电泳分析方法(MEKCE)。采用未涂层融硅毛细管分离通道，以25mmol/L十二烷基硫酸钠(SDS)-50mmol/L硼酸-三(羟甲基)胺基甲烷(Tris)缓冲液(pH8．33)为电泳介质，6．9KPa压力进样，25kV恒压电泳，25℃电泳温度，243nm检测波长。线性范围7．2-7200ng／mL(r＝0．9934)，血药浓度的最低检出量72．0ng/mL，血清标本的平均回收率为50．6％，RSD为1．2％。