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采用高效液相色谱仪同时测定化妆品中烟酸、烟酰胺的含量。样品经甲醇:去离子水(3:7)溶液萃取,HPLC测定,外标法定量。加标回收率在95.5%~102%之间,相对标准偏差为1.11%~3.71%。本方法具有良好的灵敏度和重现性,可以满足化妆品中烟酸、烟酰胺检测的要求。 相似文献
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该工作报道了一种自行设计研制的便携式微型液相色谱仪(portable micro liquid chromatograph, p-μLC)。p-μLC集成了二元大推力注射泵作为流动相驱动装置、毛细管整体柱为分离介质和紫外-可见/荧光两用流通池为在线检测单元。自行设计研制的二元大推力注射泵可以实现等度/梯度洗脱和流动相再装填功能,可控流速范围在0.025 μL/min到5.6 mL/min之间;自制的甲基丙烯酸酯C-18有机聚合物毛细管整体微柱可实现自有机小分子至生物大分子的分离;自行研制的光纤式紫外-可见/荧光两用流通池,可以通过光纤导入来自光源的紫外光和可见光,并采集透射光和与入射光反方向射出的荧光信号,流通池内使用自聚焦透镜和全反射光导毛细管等器件提高通光效率和吸收光程;两用流通池通过光纤分别连接由大功率发光二极管/脉冲氙灯光源和微型光栅光谱仪所组成的检测装置进行在线吸收和荧光光谱检测,检测波长范围为220~700 nm。p-μLC采用整体手提箱式结构,流路模块、检测模块等位于下主箱体中,采集、控制模块等位于上盖中,全重不超过8 kg。仪器由装载了自编控制采集软件的内置平板电脑进行控制和数据采集。使用自行制备的甲基丙烯酸酯C-18有机聚合物毛细管整体柱,在等度洗脱模式下,在p-μLC上分离了烷基苯化合物混合样品,其分离检测效果可以与商品化大型HPLC仪器相媲美。 相似文献
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将液相色谱仪检定规程JJG 705–2014与JJG 705–2002在检定方法、检定条件、技术指标三个方面进行对比并说明更改的缘由,对新规程进行详细解读,重点介绍新规程变化内容,最后介绍增加蒸发光散射检测器的缘由及指标。新规程使检定方法更合理,提高了检定效率,满足了市场发展的需要。 相似文献
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This study aimed to establish a rapid analytical method to determine antioxidants in essence. A simple,efficient and practical, vortex-assisted, cloud-point extraction(VACPE) procedure is proposed for extracting and pre-concentrating four different of synthetic phenolic antioxidants(SPAs), propyl gallate(PG), tert-butylhydroquinone(TBHQ), butylated hydroxyanisole(BHA), butylated hydroxytoluene(BHT) in essence prior to high performance liquid chromatography(HPLC) analysis. The non-ionic surfactant, fatty alcohol polyoxyethylene ether-9(AEO-9), was used as extractant and vortex-mixing was utilized to reduce extraction time and improve extraction efficiency. The effective parameters of the extraction process, such as volume of extraction solvent, pH, vortex-mixing time, equilibration temperature and time, were optimized. Under the optimum conditions, the linear range of PG, TBHQ,BHA and BHT was 8.0–800 ng/mL. All correlation coefficients of the calibration curves were higher than0.996 and relative standard deviations(RSD, n = 5) were 2.36%–5.46%. The proposed method was successfully applied to the extraction and determination of antioxidants in essence samples with satisfactory relative recoveries of 89.4%–103.5%. The results confirmed the SPAs of essence could be effectively monitored by this method and also established good reference criteria for essence. 相似文献
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近年来使用高效液相色谱(HPLC)来进行快速分析开始崭露头角,快速分析作为重要技术课题一直以来都是岛津致力研究的重点。 相似文献