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1.
硫酸颜色反应用于荧光法测定利血平研究   总被引:6,自引:1,他引:6  
赵一兵  王冬媛 《分析化学》1995,23(9):1055-1058
提出了硫酸颜色反应用于利血平的荧光分析新方法。利用血平与浓硫酸反应,生成强荧光物质,所得产物的荧光强度与利血平的浓度在0-0.6μg/mL范围内有良好的线性关系。检测限为0.2ng/mL。本法可直接用于尿液中利血平的定量分析,回收率为82.5%-84.2%。  相似文献   

2.
《Analytical letters》2012,45(7):1295-1306
Abstract

Oxazepam, when heated in mixtures of acetic acid and methanol, undergoes a reaction giving an intense fluorescence at excitation and emission wavelengths of 364 and 469 nm, respectively. The best reaction conditions were a 7:25 methanol:acetic acid volume ratio, a temperature of 100 °C (examinated range 50–100 °C), and a reaction time of 5 minutes. A linear range from 0.025 to 50 μg/ml with a limit of detection of 0.014 μg/ml and a reproducibility within day of less than 5% were attained. A Flow Injection Analysis method was designed and a linear range from 0.1 to 100 μg/ml with a limit of detection of 0.035 μg/ml and a reproducibility within day of less than 5% were obtained. These methods were applied to the determination of oxazepam in five pharmaceutical formulations.  相似文献   

3.
《Analytical letters》2012,45(14):2493-2502
Abstract

A method for the fluorimetric determination of fluoxetine in continuous and discontinuous systems is reported. The method is based on the hydrolysis of fluoxetine in acid medium. The fluorescent product has a spectrum with excitation and emission maxima at 253 and 306 nm, respectively. The method was applied to the determination of fluoxetine in pharmaceutical products.  相似文献   

4.
草甘膦的邻硝基苯磺酰氯柱前衍生高效液相色谱分析   总被引:2,自引:0,他引:2  
以邻硝基苯磺酰氯(NBSC)为衍生化试剂,建立了柱前衍生草甘膦的反相高效液相色谱紫外检测法,并对衍生化条件进行了优化.最佳衍生化条件为:衍生温度25℃,反应时间10 min,硼砂缓冲溶液浓度0.25 mol/L(pH 9.0),草甘膦与NBSC的摩尔比为1:5.HPLC分析条件为:采用Lichrospher C18柱,...  相似文献   

5.
阎宏涛  朱小云 《分析化学》1997,25(7):804-806
报道用催化反应热诱导激光光偏转法测定痕量尿素。发现将脲酶制成一定浓度的乙醇浓液能显著地增强激光光偏转信号强度。探讨了增强作用机理以及光偏转号强度与尿素浓度的关系,并应用于尿样中尿素含量的测定,结果满意。  相似文献   

6.
Secondary problems, such as the occurrence of side reactions and the accumulation of by-products, are a major challenge in the application of wet denitrification technology through urea solution. We revealed the formation mechanism of urea nitrate and clarified the main and side reaction paths and key intermediates of denitrification. Urea nitrate would be separated from urea absorption solution only when the concentration product of [urea], [H+] and [NO3] was greater than 0.87~1.22 mol3/L3. The effects of the urea concentration (5–20%) and reaction temperature (30–70 °C) on the denitrification efficiency could be ignored. Improving the oxidation degree of the flue gas promoted the removal of nitrogen oxides. The alkaline condition was beneficial to the dissolution process, while the acidic condition was beneficial to the reaction process. As a whole, the alkaline condition was the preferred process parameter. The research results could guide the optimization of process conditions in theory, improve the operation efficiency of the denitrification reactor and avoid the occurrence of side reactions.  相似文献   

7.
《Analytical letters》2012,45(9):771-779
Abstract

Sensitive fluorometric procedure has been developed for the determination of nitrate with resorcinol. Reaction conditions, sensitivity of the method and the effect of nitrite are discussed. It is possible to determine 5 to 70 ng of nitrate-nitrogen by the recommended method.  相似文献   

8.
建筑材料中甲醛含量的柱内衍生HPLC法测定   总被引:4,自引:0,他引:4  
选用偏二甲肼作柱内衍生剂,利用甲醛与偏二甲肼能在适当的pH值条件下生成有较强紫外吸收的偏二甲腙的实验原理,建立了内墙涂料和胶牯剂中甲醛的柱内衍生高效液相色谱测定方法。实验讨论了甲醛与偏二甲肼反应的机理、pH值对亲核加成反应的影响,估算了流动相的pH值范围为2相似文献   

9.
A fluorimetric study on the extraction of calcium into 1,2-dichloroethane as an ion-pair, formed between the cryptand 2.2.1-calcium complex and the eosinate anion, is described. Optimum conditions for extraction are established and a new fluorimetric determination of ultratraces of calcium is proposed. A linear working range from 1.5 ng ml–1 (detection limit) to 100 ng ml–1 of calcium and a relative standard deviation of ± 2.9% at the 70 ng ml–1 level are obtained. The equilibrium constants involved in the extraction process have been calculated and refined by the Letagrop-DISTR program. The proposed method has been tested for the direct determination of calcium in sugars.  相似文献   

10.
采用一种新型紫外衍生试剂对乙酰氨基苯磺酰氟(PAABS-F)作为柱前衍生试剂,成功地对19种标准D-氨基酸和甘氨酸进行了衍生和毛细管电泳分离。详细研究了各种分离条件对毛细管电泳分离的影响。实验结果表明:采用20 mmol/L硼砂(pH 9.3),126 mmol/L十二烷基硫酸钠,8 mmol/Lβ-环糊精和20mmol/L NaC l时分离结果最佳,16 m in内实现了20种氨基酸的基线分离。  相似文献   

11.
冯素玲  李俊  樊静 《分析化学》2003,31(2):198-200
基于鞣酸对Cu(Ⅱ)催化过氧化氢氧化罗丹明B具有活化作用,提出了一种简单、高灵敏度的荧光动力学测定痕量鞣酸的新方法。该方法的线性范围为0.04-0.72mg/L;检出限为0.025mg/L.该方法已成功地用于茶叶中鞣酸含量的测定.并与Folin—Ciocalteu光度法作了对照。  相似文献   

12.
阻抑动力学荧光法测定氨苄青霉素   总被引:1,自引:0,他引:1  
氨苄青霉素属于β-内酰胺类抗生素,是国内临床上广泛使用的广谱青霉素,其含量测定多采用紫外可见分光光度法[1-2]、高效液相色谱法[3]、电位滴定法[4]、化学发光法[5]、极谱法[6]等。但上述方法有的试剂繁多操作复杂,有的费时,灵敏度不高,线性范围较窄。美国药典(第23版)采用剩  相似文献   

13.
《Analytical letters》2012,45(8):1499-1513
Abstract

A sensitive fluorimetric method was developed for the determination of trace amount of europium in rare earth oxides. In the presence of gadolinium, the fluorescence of the europium complex with thenoyltrifluoroacetone and 4,7-diphenyl-1,10-phenanthroline was increased by a factor of about 2; the excitation and emission wavelengths were 346 and 613nm, respectively;the fluorescence was linear up to 1.59ng/ml of europium;and the detection limit was found to be 0.6pg/ml of europium. A general mechanism of fluorescence enhancement was proposed.  相似文献   

14.
催化荧光法测定注射用头孢哌酮钠含量   总被引:2,自引:0,他引:2  
在氢氧化钠介质中,头孢哌酮钠能催化过硫酸钾氧化光泽精褪色,使体系荧光猝灭,据此建立了测定头孢哌酮钠含量的催化荧光分析方法.头孢哌酮钠的质量浓度与荧光强度的变化在7.56~55.44 mg/L范围内呈良好的线性关系,相对标准偏差(RSD)为2.41%,方法的检出限(S/N=3)为6.95 mg/L.该法简便、快速,可靠,并应用于药物粉针制剂中头孢哌酮钠含量的测定,结果令人满意.  相似文献   

15.
合成了一种用于醇类分析的高灵敏度的荧光衍生化试剂2(4羧基苯基)4,5萘并咪唑(CNI),将其在二氯甲烷中于80℃条件下与醇缩合成酯,并采用RPHPLC法进行分离检测,色谱柱为ZorbaxBpC8柱(250mm×4.6mmi.d.),流动相为V(乙腈)∶V(甲醇)=90∶10的溶液,荧光检测波长λex345nm,λem485nm。同时,测定了人血清中的胆固醇,其最低检出质量浓度为1.0μgL。  相似文献   

16.
阻抑动力学荧光法测定痕量间苯二酚   总被引:16,自引:0,他引:16  
王瑞勇  樊静  冯素玲 《分析化学》2000,28(8):968-970
基于在HClO4介质中,间苯二酚对Fe(Ⅲ)催化H2O2氧化罗丹明6G使其荧光猝灭的抑制作用,建立了动力学荧光法测定痕量间苯二酚的新方法。线性范围为0.008~0.096mg/L间苯二酚,方法检测限为5.9ug/L。用于测定合成样中间苯二酚的含量,结果令人满意。  相似文献   

17.
 A highly sensitive fluorimetric method has been developed for the determination of gentamicin. The method is based on its coupling with 4-chloro-7-nitrobenzo-2-oxa-1,3-diazole (NBD-Cl) in 50% (v/v) methanolic phosphate buffer (pH 7.2) to give an intensely fluorescent product having excitation and emission wavelengths at 465 nm and 530 nm, respectively. The experimental parameters were carefully studied and incorporated into the procedure. The fluorescence-concentration plot is rectilinear over the range 0.56–2.8 μg/mL (r = 0.999) with minimum detectability (S/N = 2) of 0.11 μg/mL (1.6 × 10−7 mol/L). The method was applied successfully to the determination of the drug in pharmaceutical dosage forms and the percentage recoveries were satisfactorily accurate and precise. The method was further applied to spiked human plasma samples, the percentage recovery was 97.9 ± 3.4. The interference encountered from endogenous amino acids could be eliminated through selective complexation with freshly prepared copper (II) hydroxide. A proposal of the reaction pathway is presented. The method can measure the intact drug, and can be used in presence of possible interference. Received April 18, 2001; accepted April 10, 2002  相似文献   

18.
采用新型的紫外、荧光衍生试剂咔唑-9-乙基氯甲酸酯,对15种脂肪醇柱前衍生的反应条件,包括反应温度、催化剂的选择、衍生化时间等,进行了考察。结果表明:催化剂选用吡啶,反应温度80℃,时间15min,衍生化具有最大且恒定的检测响应。利用高效液相色谱对衍生产物进行分析,同时对衍生物的分离进行了优化选择,达到了较好的基线分离。检测限为13.3-93.5nmol/L。  相似文献   

19.
痕量溴的阻抑动力学荧光法测定   总被引:9,自引:0,他引:9       下载免费PDF全文
基于在磷酸介质中溴对溴酸钾氧化丁基罗丹明B反应的抑制作用,建立了痕量溴的阻抑动力学荧光分析的新方法;应用单纯形最优化法确定了 实验条件,方法的检出限0.075μg/L,线性范围0.40-6.40μg/L;将该法应用于地下水、人发中溴的分析,获得满意结果,并对反应机理进行了初步探讨。  相似文献   

20.
A simple, rapid and sensitive high performance liquid chromatography (HPLC) method was developed for the determination of metoclopramide in pharmaceutical preparation. The method is based on the derivatization of metoclopramide with fluorescamine. The separation was achieved on a C18 column using methanol‐water (70:30, V/V) mobile phase. Fluorescence detector was used at the excitation and emission of 403 and 485 nm, respectively. The method was validated for linearity, limit of detection, limit of quantification, precision, accuracy, recovery, robustness and system suitability. The assay was linear over the concentration range of 100–2000 ng/mL. The mean recovery was 100.37%. The proposed method was successfully applied to the assay of metoclopramide in tablet preparation. The preparation was also analyzed with an official method and statistical comparison by t‐ and F‐tests revealed that there was no significant difference between the results of the two methods with respect to mean values and standard deviations at the 95% confidence level.  相似文献   

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