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1.
研究了 2 羟基 5 磺酸基苯基重氮氨基偶氮苯 (HSDAA)与汞 (Ⅱ )的显色反应。在TritonX 10 0存在下 ,于pH 10 30的硼砂 氢氧化钠缓冲溶液中 ,汞 (Ⅱ )与试剂形成 1∶2的稳定橙红色配合物 ,其最大吸收波长位于 5 19nm处 ,表观摩尔吸光系数为 1 6 7× 10 5L·mol- 1 ·cm- 1 。汞 (Ⅱ )在 0~ 6 0 0 μg·L- 1 之间符合朗伯 比尔定律。该法直接应用于水样中痕量汞的测定。  相似文献   

2.
A new, simple and sensitive spectrofluorimetric method has been developed for the determination of oseltamivir phosphate (OSP) in capsules. The method is based on the reaction between oseltamivir and fluorescamine in borate buffer solution of pH 8.50 to give highly fluorescent derivatives that are measured at 483 nm using an excitation wavelength of 381. The different experimental parameters effecting the development and stability of the reaction product were carefully studied and optimized. The fluorescence intensity concentration plot is rectilinear over the range 50–450 ng mL−1 with a lower detection limit (LOD) of 1.219 ng mL−1 and limit of quantitation (LOQ) of 4.064 ng mL−1. Selectivity was validated by subjecting stock solution of OSP to acidic, basic, oxidative, and thermal degradation. No interference was observed from excipients present in formulations. The developed method was successfully applied to determination of the drug in capsules. The mean % recovery (n = 6) was 100.08. The results obtained were in good agreement with those obtained using a reported spectrophotometric method.  相似文献   

3.
A highly sensitive flow-injection spectrofluorimetric method is presented for the rapid and simple determination of Hg (II) in environmental and pharmaceutical samples. Murexide (ammonium purpurate) was used as the fluorescence reagent in the carrier stream. An emission peak of murexide, which is decreased linearly by addition of Hg (II), occurs at 435 nm in aqueous solution with excitation at 335 nm. A linear calibration was obtained for 5–200 ng ml−1 Hg (II) with the relative standard deviation 2.5% (n = 5) for a 20 μl injection volume Hg (II). The limit of the detection was 1 ng ml−1 and the sampling rate was 80 h−1. No significant interference was found by the ions commonly found in the most environmental samples. The proposed method was successfully applied for the determination of trace mercury in real samples and the validation of the proposed methodology is provided.  相似文献   

4.
香菇中甲醛的提取与测定   总被引:4,自引:0,他引:4  
王宝仁  董彩霞 《光谱实验室》2010,27(3):1223-1225
用乙酰丙酮分光光度法测定香菇在不同温度下浸泡不同时间的浸出液中甲醛含量,实验结果表明,用60℃的水浸泡40min或40℃的水浸泡60min可最大限度浸出香菇中的甲醛,为健康食用香菇提供理论依据。  相似文献   

5.
比色法测定纺织品中甲醛含量的确认研究   总被引:3,自引:0,他引:3  
颜红 《光谱实验室》2004,21(1):79-82
对纺织品中的甲醛含量测定的乙酰丙酮比色法中双甲酮确认试验进行了研究 ,发现在乙酰丙酮存在下双甲酮与甲醛的反应会发生逆反应 ,指出了文献方法中这一部分叙述的不准确之处  相似文献   

6.
研究了盐酸介质中N-(1-萘基)-乙二胺(NED)与亚硝酸根的反应。基于NED的荧光强度被亚硝酸根猝灭的现象,建立了一种荧光测定NO-2的新方法,并对反应机理进行了讨论。在优化实验条件下,NO-2在1.07~214.0 μg·L-1范围内与NED的荧光猝灭强度呈线性关系,方法的检出限为0.069 μg·L-1。该法用于测定水样中痕量亚硝酸根的含量,结果令人满意。  相似文献   

7.
8.
Simple, accurate and sensitive spectrofluorimetric method has been proposed for the determination of three cephalosporins, namely; cefixime (cefi), cephalexine (ceph), cefotaxime sodium (cefo) in pharmaceutical formulations. The method is based on a reaction between cephalosporins with 1, 2-naphthoquinone-4-sulfonic (NQS) in alkaline medium, at pH values of 12.0 for cefi and 13.0 for ceph and cefo to give highly fluorescent derivatives extracted with chloroform and subsequently measured at 600,580 and 580 nm after excitation at 520,455 and 490 nm for cefi, ceph and cefo respectively. The optimum experimental conditions have been studied. Beer’s law is obeyed over the concentrations of 10–35 ng/mL, 10–60 ng/mL and 20–45 ng/mL for cefi,ceph and cefo, respectively. The detection limits were 2.02 ng/mL, 2.09 ng/mL and 2.30 ng/mL for cefi, ceph and cefo, respectively, with a linear regression correlation coefficient of 0.9987, 0.9995 and 0.9991 and recoveries in range from 98.5-107.04, 95.17-101.00 and 95.00-109.55% for cefi, ceph and cefo, respectively. This method is simple and can be applied for the determination of cefi, ceph and cefo in pharmaceutical formulations in quality control laboratories.  相似文献   

9.
A simple, economic, selective, and stability indicating spectrofluorimetric method was developed for the determination of famotidine (FMT); is based on its reaction with 9, 10-phenanthraquinone in alkaline medium to give a highly fluorescent derivative measured at 560 nm after excitation at 283 nm. The fluorescence intensity - concentration plot was rectilinear over the concentration range of 50–600 ng/ml with minimum quantification limit (LOQ) of 13.0 ng/ml and minimum detection limit (LOD) of 4.3 ng/ml. The factors affecting the development of the fluorescence intensity of the reaction product were carefully studied and optimized. The method was applied for the determination of FMT in its dosage forms. The stability of the compound was studied, and the proposed method was found to be stability indicating one. The results obtained were in good agreement with those obtained by the official method. Furthermore, the method was applied for the determination of FMT in spiked and real human plasma. The mean % recovery (n = 4) was found to be 99.94 ± 0.24, and 105.13 ± 0.64 for spiked and real human plasma, respectively. The composition of the reaction product as well as its stability constant was also investigated. Moreover, the method was utilized to investigate the kinetics of both alkaline and oxidative induced degradation of the drug. The apparent first order rate constant and half life time of the degradation product was calculated. A proposal of the reaction pathway was postulated.  相似文献   

10.
Spectrophotometric and spectrofluorimetric procedures for the quantitative determination of four penicillins [Amoxycillin (AMX), Bacampicillin (BAC), Piperacillin (PPN) and Sultamcillin (SULT)] and ten cephalosporins [Cefadroxil (CDL), Cefamandole nafate (MAN), Cefuroxime axetil or sodium (CFX), Cefaclor (CFCR), Ceftazidime (CZD), Ceftizoxime (CTIZ), Ceftriaxone (CTRX), Cefoperazone (CPZ), Cefixime (CXIM) and Cefpodoxime proxetil (CFPD)] are described. Both methods are based on the acidic oxidation of the antibiotics with cerium (IV) at elevated temperature. The effect of the reagent concentration, volume of the acid,and the heating temperature were studied to optimize the reaction conditions. Each antibiotic was determined by either measuring the absorbance difference at 317 nm or the cerous inherent fluorescence at 256 and 356 nm for excitation and emission wavelengths, respectively. The two procedures have been successfully applied to the assay of these antibiotics in their pharmaceutical dosage forms. The obtained results have been statistically compared with those obtained by the official methods.  相似文献   

11.
应用荧光光谱法研究了盐酸表阿霉素与血清白蛋白之间的相互作用,求得它们之间的结合常数KA=2.342×10~4(t=25℃),KA=1.993×10~4(t=35℃),KA=1.638×10~4(t=45℃),以及金属离子对结合常数的影响,确定了药物与血清白蛋白之间的相互作用力,并根据Forster非辐射能量转移理论求出给体-受体间的结合距离r=4.25 nm和能量转移效率E=0.018。又进一步在生理条件下成功的测定了药物在血清与尿样中的含量。  相似文献   

12.
建立了用二甲酚橙作为显色剂直接测定痕量锡的新方法 ,锡与二甲酚橙在pH 3 5时形成的络合物 ,加入聚乙烯醇使稳定性大大提高 ,实验条件下显色络合物的最大吸收峰位于 5 4 4nm处 ,表观摩尔吸光系数ε =4 38× 10 5,线性范围为Sn 0 1~ 5 μg· (2 5mL) - 1 ,回收率为 97 4 %~ 10 1 1%。此方法选择性好、灵敏度高、操作简单 ,此方法用于分析水样中的微量锡 ,结果令人满意。  相似文献   

13.
A sensitive, simple and selective spectrofluorimetric method was developed for the determination of oxamniquine (OXM) in pharmaceutical formulations and biological fluids. The method is based on the reaction between the drug and 1-dimethylaminonaphthalene-5-sulphonyl chloride (dansyl chloride) in presence of 0.5 M sodium carbonate (pH 10) to yield a highly fluorescent derivative that is measured at 445 nm after excitation at 335 nm. The different experimental parameters affecting the development and stability of the reaction product were carefully studied and optimized. The fluorescence concentration plot was rectilinear over the range of 0.02–0.2 μg ml−1 with a lower detection limit (LOD) of 0.007 μg ml−1 and limit of quantitation (LOQ) of 0.02 μg ml−1. The proposed method was successfully applied to the analysis of commercial capsules. The results obtained were in good agreement with those obtained using the official spectrophotometric method. Furthermore, the method was applied for the determination of oxamniquine in spiked human plasma, the mean % recovery (n = 4) is 97.77 ± 1.19. A proposal of the reaction pathway was presented.  相似文献   

14.
ICP-AES法同时测定人血清中16种元素含量   总被引:3,自引:0,他引:3  
本文探讨了用电感耦合等离子体原子发射光谱(ICP-AES)法同时测定了人血清中Na、K、Ca、Mg、Co、Mo等16种元素的方法。采用工艺超纯硝酸消化,基体匹配消除干扰。本法最低检出限能满足血清样品的测定要求,回收率在95%-106%之间,对探索血清微量元素与疾病的关系有着重要意义。  相似文献   

15.
The simultaneous determination of zinc and cadmium using derivative synchronous and multiwavelength synchronous spectrofluorimetry is described. Effects of experimental variables on the fluorescence intensities and on the spectral resolution of the fluorescent chelates of these metals with 8-(p-toluenesulfonamido)-quinoline (TSQ) in a sodium lauryl sulfate micellar medium have been studied. Mixtures containing 10–200 g L–1 Zn and 15–250 g L–1 Cd have been analyzed with good results. The proposed method has been applied to a biological sample.  相似文献   

16.
催化动力学光度法测定痕量铜的研究进展   总被引:12,自引:1,他引:11  
本文探讨和论述了近年来催化动力学光度法测定痕量铜的研究进展,比较了催化光度法与原子吸收法、萃取光度法的优缺点;介绍了催化动力学光度法的原理;评述了催化褪色光度法、催化显色光度法、催化荧光光度法等的研究进展,探讨和展望了催化动力学光度法未来的研究方向和发展前景,包括:1.对传统显色剂改性或合成新的高灵敏度、高选择性显色剂;2.活性剂增敏研究;3.加强相关催化机理的研究和探讨。全文参考文献29篇。  相似文献   

17.
分光光度法测定环境水样中痕量镉   总被引:3,自引:1,他引:3  
罗育池  林春 《光谱实验室》2003,20(5):790-792
在 p H8 .5的氨 -氯化铵缓冲溶液中 ,有 CTMAB存在下 ,镉与 5 - Br- PADAP形成红色络合物。最大吸收波长为 5 6 0 nm,表观摩尔吸光系数为 2 .18× 10 5L· mol-1· cm-1。络合物的配合比为镉 ( )∶ 5 - Br-PADAP=1∶ 2 ,镉量在 0— 10 μg/ 2 5 m L范围内符合比耳定律。本法灵敏度高 ,有色络合物稳定 2 0 h以上 ,应用于环境污水中微量镉的测定 ,获得了满意的结果  相似文献   

18.
A rapid and sensitive spectrofluorimetric method was developed and validated for the determination of erlotinib (ETB), a potent anticancer drug, in spiked human plasma without any derivatization. The described method was validated and the analytical parameters of linearity, accuracy, precision (intra- and inter-day), limit of detection (LOD), and limit of quantification (LOQ) were evaluated. The relation between the fluorescence intensity and concentration was found to be linear (r2 0.9998) over the range 125 to 1000?ng/mL with the detection limit of 15?ng/mL. A simple liquid-liquid extraction method was followed in order to extract the drug from spiked plasma. The mean absolute recoveries of ETB were 85.59?% (±0.57), 86.91?% (±1.77) and 89.31?% (±3.01) at spiked plasma ETB concentration of 5000, 3750 and 2500?ng/mL, respectively. The spectrofluorimetric method presented here is a rapid, simple, specific, and reproducible method and can be used to characterize the plasma pharmacokinetics of ETB.  相似文献   

19.
4-硫-5-碘尿苷的合成及其与人血清白蛋白间的相互作用   总被引:2,自引:2,他引:0  
基于硫碱基(thio-base)的易烷基化、易氧化、强紫外长波(UVA)吸收等独特的性质,以及核苷类化合物的抗肿瘤活性,设计合成了一种新化合物4-硫-5-碘尿苷,通过NMR、IR、UV、MS对其结构进行了表征。在模拟生理条件下,利用荧光光谱法、紫外-可见吸收光谱法以及圆二色谱法研究了4-硫-5-碘尿苷与人血清白蛋白(HSA)的相互作用。结果表明,4-硫-5-碘尿苷对HSA荧光具有静态猝灭作用。运用Stern-Volmer方程计算了体系的猝灭常数,利用Lineweaver-Burk方程计算了二者的结合常数,并且确定了4-硫-5-碘尿苷与HSA之间的主要作用力类型为疏水作用力,根据能量转移理论求得4-硫-5-碘尿苷与HSA的结合距离及能量转移率。此外,通过圆二色谱法考察了4-硫-5-碘尿苷对HSA作用前后的构型结构的影响。  相似文献   

20.
电热蒸发ICP-AES法直接测定人血清中微量元素   总被引:1,自引:0,他引:1  
建立了悬浮体制样电热蒸发电感耦合等离子体原子发射光谱法(ETVICPAES)直接测定人血清中微量元素(Cu,Cr,Fe)的方法。采用聚四氟乙烯(PTFE)悬浮体为化学改进剂,以促进待测物的蒸发,改善方法的分析性能。研究了影响待测元素信号强度的主要因素。在优化实验条件下,方法的检出限为14ng·mL-1(Cu)和29ng·mL-1(Fe),相对标准偏差小于60%。  相似文献   

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