共查询到20条相似文献,搜索用时 15 毫秒
1.
痕量苯胺的动力学荧光法测定 总被引:7,自引:0,他引:7
在磷酸介质中,痕量苯胺对过碘酸钾氧化罗丹明6G使其荧光猝灭具有抑制作用,据此建立了动力学荧光法测定痕量苯胺的新方法。方法的线性范围为0.010~0.183 μg·mL-1,检出限为7.2 ng·mL-1。本法灵敏度高、线性范围宽,用于测定酚醛塑料管材和水样中苯胺的含量,回收率在100%~104% 之间,结果令人满意。 相似文献
2.
An inhibitory kinetic fluorimetric method is reported for the determination of trace bisphenol S (BPS). The proposed method is based on the inhibitory effect of BPS on the fluorescence quenching of rhodamine B (RhB) caused by potassium bromate in a dilute phosphoric acid medium. Under the optimal conditions of the experiment, the detection limit for BPS was 0.021 mg/L, and the linear range of determination was from 0.035 mg/L to 0.750 mg/L. The relative standard deviations of 11 measurements for 0.20 mg/L and 0.40 mg/L BPS solutions were 2.74 % and 1.87 %, respectively. The method was successfully applied to the determination of bisphenol S derived from commercially available plastic film samples in hot water. A possible reaction mechanism of the inhibitory effect of BPS on the fluorescence quenching of RhB was proposed. 相似文献
3.
A new spectrofluorimetric method for the determination of cytochrome c using spirocyclic rhodamine B hydrazide (RBH) as fluorogenic
reagent in the presence of sodium dodecylbenzene sulfonate (SDBS) surfactant micelles was developed. The method was based
on the reaction of cytochrome c with RBH, a colorless, nonfluorescent spirolactam of rhodamine B in SDBS micelles to give
highly fluorescent rhodamine B and hence led to a large increase in fluorescence intensity. The dynamic range and detection
limit for the determination of cytochrome c are 4.0–120 ng ml−1 and 0.87 ng ml−1 (3σ), respectively. The optimal conditions for the detection of cytochrome c were evaluated and the possible detection mechanism
was also discussed. 相似文献
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5.
催化荧光法测定痕量草酸 总被引:3,自引:0,他引:3
在硫酸介质中 ,草酸能催化重铬酸钾氧化罗丹明B褪色 ,使体系荧光猝灭 ,建立了催化荧光法测定草酸的新方法。催化反应在 50℃水浴中进行 1 0min ,为假零级反应。测定草酸的线性范围为 0 4~ 1 2 0mg·L- 1 ,其回归方程为ΔF =8 42c(mg·L- 1 ) 3 81 ,r=0 9983 ,检出限为 0 1 6mg·L- 1 。试验了 30种共存物质的干扰情况。此法用于生物样品中草酸含量的测定 ,结果满意。 相似文献
6.
ICP-AES氢化物发生法测定生物样品中的痕量硒 总被引:7,自引:0,他引:7
本文研究了ICP-AES氢化物发生法测定生物样品中痕量硒的方法。对氢化物发生条件和样品消化过程进行了选择,并使之达最佳化。方法检出限达0.09ng/ml。 相似文献
7.
流动注射-多道检测-催化动力学同时测定铜和铁 总被引:10,自引:0,他引:10
基于Cu(Ⅱ),Fe(Ⅲ)在pH3~9范围内能同时催化过氧化氢氧化罗丹明B的褪色反应,探讨了最佳反应条件,通过构建流动注射pH梯度,采用CCD-二极管阵列检测器检测吸光度差值,反向传播-人工神经网络(BP-ANN)处理数据,实现了Cu(Ⅱ),Fe(Ⅲ)流动注射-催化动力学光度法的同时测定。Cu(Ⅱ)和Fe(Ⅲ)的检出限分别为0.10和0.21μg·L~(-1),采样频率为10次·h~(-1),本法用于标准参考物质和食品样品中铜、铁的同时测定,结果满意。 相似文献
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9.
Strong chemiluminescence (CL) emission was observed when sodium new houttuyfonate (SNH) was mixed with Tween 80 in sulfuric
acid medium in the presence of rhodamine B. Base on this phenomenon, a sensitive flow injection-CL method for the determination
of SNH was developed. Under the optimum conditions, the CL emission is linearly with SNH concentration in the range 8.0–4000 ng mL−1, with a detection limit of 2.7 ng mL−1 (3σ). As a preliminary application, the proposed method was successfully applied to the determination of SNH in pharmaceutical
preparations. The possible CL mechanism was also discussed in this paper. 相似文献
10.
A new method for the spectrofluorimetric determination of indium by formation of a fluorescent 1:1 complex with 1,2,4-trihydroxyanthraquinone is proposed. The complex is formed in a mixed, 60:40 v/v acetone-water medium at pH 3.8 provided by an acetic acid-sodium acetate buffer. The calibration graph is linear between 10 and 600 ng/ml. The effect of potential interferents on the determination was assessed and the proposed method was applied to the determination of indium in synthetic samples. 相似文献
11.
A water-soluble fluorescent probe, rhodamine B hydrazide (RBH), was prepared and its properties for recognition of diacetyl
were studied. The method employs the reaction of diacetyl with RBH, a colorless and non-fluorescent rhodamine B spiro form
derivative to give a pink-colored fluorescent substance. In weakly acidic media, RBH reacts more selectively with diacetyl
than with other carbonyls, causing a large increase in fluorescence intensity and thereby providing an easy assay for the
determination of diacetyl. 相似文献
12.
N. V. Gaponenko T. I. Orekhovskaya I. A. Nikolaenko O. P. Linnik M. A. Zhukovskii N. P. Smirnova S. Ya. Prislopskii 《Journal of Applied Spectroscopy》2010,77(3):432-436
We have used the sol–gel method to synthesize titanium dioxide in the pores of an anodic aluminum oxide membrane. The samples
were used for the test reaction of degradation of the organic dye rhodamine B. The concentration of the dye rhodamine B was
monitored from the change in the absorption spectra in the 554 nm region, for an aqueous solution containing the dye and exposed
to the emission from a mercury lamp. The synthesized samples of titanium oxide xerogel in the porous anodic aluminum oxide
membrane are efficient photocatalysts for decomposition of organic dyes in an aqueous medium. 相似文献
13.
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
14.
Bao-xiu Jia Yu-qin Li Cai-hong Liu Ke Li Yong-xiu Qi 《Journal of luminescence》2010,130(11):2188-2191
A novel flow injection chemiluminescence (CL) analysis method for the determination of metoclopramide in the presence of sodium dodecyl sulfonate (SDS) surfactant micelles is described. This method is based on the luminescent properties of the KMnO4-HCHO-metoclopramide in acid medium sensitized by SDS. The optimized experimental conditions were evaluated and the possible mechanism was discussed. The CL increase is linearly related to the concentration of metoclopramide in the range 0-80.0 μg/ml with a detection limit of 31.3 ng/mL (S/N=3).The relative standard deviation for 20.0 μg/ml samples was 2.6% (n=11). The proposed method has been successfully applied to the determination of metoclopramide in tablets. 相似文献
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Abstract The resonance light scattering (RLS) spectra of ethyl rhodamine B with nucleic acid (calf thymus DNA and herring sperm DNA) have been studied. The effective factors and the optimum conditions have been studied, and the enhanced intensity of RLS is in proportion to the concentration of nucleic acids in the range 0~5.00 µg mL?1 for calf thymus DNA (ctDNA) and 0~3.50 µg mL?1 for herring sperm DNA (hsDNA). The limits of detection are 3.42 and 3.14 ng mL?1, respectively. Based on this, a RLS method for the determination of nucleic acids sensitized by emulsifier OP‐micelle was accordingly established. The binding mode concerning the interactions of ethyl rhodamine B with nucleic acids was also studied, and this method has good selectivity and high sensitivity and it has been applied to the determination of DNA in synthetic samples and real samples with satisfactory results. 相似文献
17.
催化分光光度法测定辣根过氧化物酶新方法研究 总被引:8,自引:2,他引:6
本文基于微量辣根过氧化物酶 (HRP)对过氧化氢氧化还原型罗丹明B这一显色反应的催化作用 ,建立了一个高灵敏度测定HRP及其酶标记结合物的催化光度新方法 ,探讨了该催化反应体系的反应条件及干扰情况 ,实验表明 β CD能显著增强还原型罗丹明B的稳定性 ,邻苯二胺对该催化反应有催化诱导作用。应用于测定痕量辣根过氧化物酶 ,其检出限为 12pg·mL-1,其线性范围为 15~ 2 5 0pg·10mL-1,RSD为4 2 5 % (n =10 )。 相似文献
18.
催化荧光法测定痕量亚硝酸根 总被引:13,自引:0,他引:13
在稀磷酸介质中 ,溴酸钾可氧化吖啶橙使之褪色并伴随着吖啶橙荧光强度的减弱 ,但反应速率较慢。痕量亚硝酸根的存在对该反应可起到显著的催化作用 ,使反应的灵敏度明显提高 ,体系的荧光猝灭程度加强。基于此采用固定时间法提出了一种灵敏度高、选择性好的催化荧光法测定痕量亚硝酸根的新方法 ,并研究了该方法的动力学条件。催化反应在λex/λem =4 4 6 / 5 0 5nm处 ,5 5℃水浴中进行 10min。反应可允许较大量的 2 0多种常见离子存在 ,同倍量的Fe3 ,Br-、I-不干扰。亚硝酸根的线性范围为 0 0 5~ 5ng·mL-1,方法的检出限为 0 0 12ng·mL-1。用于水体和土壤中痕量亚硝酸根的测定 ,结果满意。 相似文献
19.
食品安全问题越来越严重,汞作为有害离子之一受到人们的广泛关注,为了寻求茶叶和火腿肠中汞含量测定的新方法。首先以罗丹明B, 肼水化合物, 邻羧基苯甲醛为原料反应生成一种新型的Hg2+荧光增强型探针;接着,通过荧光光谱仪测量探针与不同浓度汞离子络合后的荧光强度,研究汞离子浓度与荧光强度的关系, 绘制出标准工作曲线;然后,对茶叶进行微波消解,消解后用合成的探针测定茶叶中汞的含量。结果表明:探针和络合物的最大激发波长为568.05和560.00 nm, 最大发射波长为587.94和580.00 nm;检测的适宜条件为:溶剂为50%甲醇水溶液,3.0 mL pH 4.0的缓冲溶液,反应时间30 min内。该探针对Hg2+有很好的选择性,Na+, K+, Ca2+, Cu2+, Zn2+, Al3+对此探针的荧光强度几乎没有影响,Fe3+, Mg2+, Ba2+对此探针的荧光强度仅有微弱的增强,而很低浓度的Hg2+对此探针的荧光强度有显著的增强作用。Hg2+浓度在5~20 ng·L-1范围内线性相关系数为0.951 2,检出限为1.9 ng·L-1;对茶叶和火腿肠样品进行Hg2+加标回收实验,标准回收率分别为101.1%,92.6%。该方法仪器结构简单,灵敏度, 准确度高,选择性好且用样量少,无需富集,有很强的实用性。 相似文献
20.
激光诱导荧光光度法测定食品中的锌 总被引:3,自引:0,他引:3
本文利用自行组装的激光诱导荧光 CCD阵列检测器 计算机联用装置 ,建立了一种测定食品中锌的灵敏方法。在乙酸 乙酸铵 ( pH =4 )缓冲溶液中 ,Zn(Ⅱ )与SCN、罗丹明B(RhB)反应生成Zn SCN RhB配合物 ,经乙醚萃取后 ,以YAG激光二倍频 5 32nm为激发波长 ,在 5 80nm处测定荧光强度 ,优化了反应及食品样品的处理条件 ,用于食品试样中锌的测定 ,获得了满意的结果 ,方法检出限 4ng/mL ,加标回收率90 0~ 1 1 0 0 % ,相对标准偏差为 2 0~ 9 7%。 相似文献