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在线分子印迹-化学发光法对食品中苏丹红Ⅰ的测定 总被引:1,自引:0,他引:1
以苏丹红Ⅰ作模板分子,用悬浮聚合法制备出微米级苏丹红Ⅰ分子印迹聚合物并将其做成微固相萃取柱,直接安装在流动注射系统的八通阀上,对样品溶液中的苏丹红Ⅰ进行在线分离和富集;经甲醇和甲酸混合洗脱液(体积比2:1)在线洗脱后与酸性高锰酸钾发生化学发光反应。据此建立了在线分子印迹微固相萃取,高锰酸钾氧化苏丹红化学发光测定食品中苏丹红Ⅰ的新方法。结果表明,测定的苏丹红Ⅰ线性范围为1.0×10^-6~7.0×10^-4g/L,方法检出限(3仃)为3×10^-7g/L,11次平行测定1×10^-5g/L苏丹红Ⅰ溶液的化学发光强度相对标准偏差为2.0%。 相似文献
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脱水穿心莲内酯琥珀酸半酯单钾盐(穿琥宁, DAS-K)具有清热解毒、抗菌消炎功能, 在临床上广泛用于病毒性肺炎、疟疾和呼吸道感染等疾病的治疗。本文基于NaOH碱性介质中,在罗丹明B的存在下,铁氰化钾可以直接氧化穿琥宁产生化学发光这一现象,建立了一种利用化学发光测定中药穿琥宁的新方法。优化了化学发光反应的条件并讨论了可能的反应机理。在优化实验条件下,该法测定DAS-K的线性范围为0.1~80
µmol•L−1,检出限为0.05µmol•L−1。在此基础上,结合在线微超滤技术,测定了DAS-K和牛血清白蛋白作用后未结合DAS-K的浓度,以Scatchard和Klotz方程作图求解,得出了DAS-K和与牛血清白蛋白相互作用的结合常数,为中药与蛋白相互作用的研究提供了一种简单、快速的在线微超滤化学发光新方法。 相似文献
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化妆品样品用甲醇提取使苯甲酸及山梨酸溶于溶剂中,经离心分离,取上层清液,通过反相C18固相萃取小柱纯化。取其流出液经过滤和脱气后,用于高效液相色谱法分析。取20μL进样,在Hypersil C18反相色谱柱(柱温30℃)上进行分离,所用流动相为甲醇与0.02 mol.L-1乙酸铵(15+85)混合溶液,流量为0.8 mL.min-1。采用紫外检测,检测波长为221 nm,测得苯甲酸和山梨酸的检出限(3S/N)分别为0.04,0.08 mg.L-1。用5 mg.L-1的苯甲酸和山梨酸标准溶液作精密度试验,测得两者的相对标准偏差(n=7)分别为2.8%及2.5%,向实际样品中加上述两种酸的标准溶液作回收试验,测得回收率在85.0%~106.7%之间。 相似文献
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Potassium dehydroandrographolide succinate (DAS-K) has antibacterial and antiviral effects. It has been used widely for the treatment of virus pneumonia, malaria and respiratory infections. In this work, a novel flow-injection chemiluminescence (CL) method for the determination of DAS-K was proposed. The method is based on the reaction between DAS-K and hexacyanoferrate(III) in alkaline solution to give weak CL signal, which is enhanced by rhodamine B. The experimental conditions for the CL reaction were optimized and the possible reaction mechanism was discussed. Under the optimum conditions, the concentration of DAS-K is proportional to the CL intensity in the range of 0.1-80 μmol·L^-1 with a detection limit of 0.05 μmol·L^-1. The interaction of the DAS-K with bovine serum albumin by on-line ultrafiltration and flow-injection chemiluminescence was studied. The concentrations of unbound DAS-K from ultra filter tube were determined by the flow-injection CL method. The binding parameters were estimated by the Scatchard plot and Klotz plot. The proposed system proved that FIA-CL coupled with on-line ultrafiltration sampling was a fast and simple technique for the study of drug-protein interaction. 相似文献
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