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1.
研究了在稀硫酸介质中亚硝酸根与吖啶红发生的亚硝化反应,建立了测定痕量亚硝酸根的荧光猝灭法。方法的测定范围为0.01~0.70μg·ml-1。方法用于环境水样中痕量亚硝酸根的测定,结果满意。 相似文献
2.
1引言测定痕量亚硝酸根,光度法仍是最重要的一类方法,但常规光度法如Griess法等灵敏度较低,而另一系列基于通过NO-2的重氮化和偶联反应,形成偶氮染料的光度法,均需使用有毒试剂。在稀磷酸溶液中,NO-2对KBrO3氧化吖啶红(Acridinered,C.I.45000,缩写为ADR)的褪色反应具有很强的催化作用,以此反应为指示反应,建立了测定痕量NO-2的新方法,用于多种样品中NO-2的测定,结果满意。2.2实验部分2.1仪器及试剂澳大利亚GBCUV/VIS916分光光度计(带恒温比色架),T… 相似文献
3.
研究了在稀盐酸介质中吖啶红与亚硝酸根发生亚硝化反应,建立了极谱法测定亚硝酸根的新方法。反应产物的2.5次微分波的峰谷电位为-0.49V,亚硝酸根浓度在0.02-0.6μg.ml^-1范围内与峰高呈线性关系,检出限为6.2*10^-3μg.ml^-1。相对标准偏差为1.84%,用于测定环境水样中亚硝酸根,结果满意。 相似文献
4.
以溴酸钾与水杨基荧光酮的氧化-还原反应为指示反应,以水杨基荧光酮荧光变化为测定依据,系统研究了亚硝酸根催化荧光熄灭反应的动力学条件,建立了水杨基荧光酮催化动力学荧光熄灭法测定自来水中痕量亚硝酸根的方法。用固定时间法得到了良好的工作曲线lgF0/F= 1.305 c-0.017 5,线性范围为0.1~0.5μg/25 mL,线性相关系数为0.999 0。该方法的检出限为1.6μg·L-1。水样测定结果的相对标准偏差为3.7%,加标回收率为95%~106%。 相似文献
5.
研究了用荧光猝灭法测定了亚硝酸根。本方法是基于亚硝酸根与碘化钾反应生成了单质碘,碘可以使2’,7’0二氯荧光素(DCF)发生荧光猝灭,从而间接测定亚硝酯根。亚硝酸根浓度在10 ̄120μg/L范围内,荧光强度差值与亚硝酸根浓度呈线性关系。检测限为5.6μg/L。本法简便、灵敏度较高,已用于合成样和分析纯试剂中亚硝酸根的测定。 相似文献
6.
在稀盐酸溶液中,Se(Ⅳ)与碘化钾反应生成碘分子,碘分子与吖啶红反应,使其发生荧光猝灭反应,荧光猝灭值在一定范围内与硒(Ⅳ)浓度呈线性关系,据此建立了测定痕量硒的荧光猝灭方法。方法的测定范围为0.01~O.20μg·ml-1。方法用于金属锰中痕量硒的测定,结果满意。 相似文献
7.
研究了在盐酸介质中NO^-2与中性红的亚硝化反应。结果表明,在0.048mol/L的盐酸介质中,NO^-2与中性红反应生成无荧光的物质,NO^-2在40-240μg/L,范围内与荧光猝灭程度成正比,常见的共存离子不干扰其测定。所拟方法用于水样中NO^-2的测定,结果满意。 相似文献
8.
在硫酸介质中,亚硝酸根能还原吡咯红Y,使其荧光猝灭据此提出了一个测定痕量亚硝酸根的荧光分析法,方法的检出限为2.7ng/mL,线性范围为6.0-88ng/mL,可直接用于电厂废水、自来水、井水中亚硝酸根的测定。 相似文献
9.
1 引 言亚硝酸根与芳胺或苯甲胺反应因生成致癌物质亚硝胺而引起广泛的关注。测定亚硝酸根的方法除经典的Griess法外还有分光光度法、荧光法、催化动力学法等 ,但利用罗丹明 3GO与亚硝酸根发生的荧光熄灭法测定亚硝酸根的方法尚未见报道。本研究发现 ,在盐酸介质中 ,亚硝酸根的加入使罗丹明 3GO荧光强度明显降低 ,其降低程度与亚硝酸根的加入量间存在着良好的线性关系 ,从而建立了用罗丹明 3GO荧光熄灭法测定亚硝酸根的新方法。方法操作简单 ,灵敏度高 ,重现性好 ,可直接测定水样中的亚硝酸根。2 实验部分2 .1 仪器和试剂… 相似文献
10.
基于在柠檬酸(0.06mol.L^-1)介质和抗坏血酸(0.008mol.L^-1)存在下,VO^-3离子催化KBrO3(0.004mol.L^-1)氧化吡罗红Y(6×10^-6mol.L^-1)荧光定量熄灭建立了测定痕量钒的新方法,VO^-3浓度在0~50ng/25ml范围内与吡罗红Y相对荧光强度△F呈直线关系,方法灵敏度高,选择性好,可直接测定水样和人发中的钒。 相似文献
11.
在HCl介质中,NO2-与5-氨基-1,2,3,4-四氢-1,4酞嗪二酮(ATPD)发生亚硝化反应,使ATPD的荧光猝灭,且其荧光猝灭程度与NO2-量呈线性关系,从而建立了测定痕量NO2-的新方法。该法线性范围为0.067~1.172μg/mL,方法检出限为0.70μg/L。本法已用于雨水中痕量NO2-的测定。 相似文献
12.
The carbazole derivative, with an amino group in 9-position (9-methylacryloylamino carbazole (MAC), has been utilized to prepare a fluorescent sensor and used for the determination of NO 2− based on the reaction between nitrite (NO 2−) and excess I − to form I 3−, which can quench the fluorescence of carbazole derivative. MAC, as a fluorescent carrier, has a terminal double bond and is covalently immobilized on a quartz glass plate surface by photo-polymerization to prevent the leakage of the dye. The sensor shows sufficient repeatability, selectivity, operational lifetime of 8 weeks, and a fast response of less then 30 s. NO 2− can be determined in the range between 1.0×10 −6 and 1.0×10 −4 mol l −1 with a detection limit of 8.0×10 −7 mol l −1 at pH of 2.0. The quenching mechanism is discussed. Most commonly coexisting ions do not interfer with the NO 2− assay. 相似文献
13.
建立了吖啶橙(AO)-罗丹明6G(R6G)共振能量转移荧光猝灭法测定尿中1-羟基芘的新方法.在λex/λem=470/556nm,十二烷基苯磺酸钠(SDBS)存在下,AO-R6G能够发生有效的能量转移,使R6G的荧光大大增强;1-羟基芘(1-OHP)的加入使R6G的荧光猝灭.方法的线性范围是21.3~982 μg/L;检出限为6.4 μg/L;平行7次测定相对标准偏差为0.98%~2.0%;回收率为96.0%~104.4%.该方法用于锅炉工尿样中1-羟基芘的测定,结果与常规的高效液相色谱法一致. 相似文献
14.
A simple, sensitive and selective fluorimetric method for the determination of nitrite ion in waters using a merging zones flow injection system is described. The fluorimetric determination is based on the measurement of the quenching effect produced by nitrite on proflavine (3,6-diaminoacridine) fluorescence (λ ex/λ em=290/519 nm). The optimum experimental conditions were investigated by merging 0.5 ml of the sample and 0.5 ml of a solution of 5 mg l−1 of proflavine (in 0.1 M HCl) in a flow injection system, on-line connected to a flow-cell placed in the conventional sample compartment of a spectrofluorimeter. The selected carrier solution and final flow rate were 0.1 M HCl and 0.5 ml min−1, respectively. A reaction coil of 2 ml was used. As a result of the simplicity of this system, a sample throughput of about 50 samples h−1 can be achieved with the proposed methodology. The detection limit was 1.1 ng ml−1 (3σ criterion) of nitrite. The repeatability for five sample injections containing 100 ng ml−1 of nitrite was ±0.3% and the observed linear range extended up to 400 ng ml−1. Also, the effect of interferences from various metals and anions commonly present in waters was also studied. The method was successfully applied to the determination of low levels of nitrite in different water samples (river, fountain, tap and commercial drinking waters). 相似文献
15.
研究了吖啶橙(AO)与罗丹明B(RB)间发生能量转移的最佳条件,在pH=6.80的Britton-Robinson(B-R)缓冲溶液,十二烷基苯磺酸钠的介质中,AO-RB间发生有效能量转移,使RB荧光大大增强,叶酸(FA)的加入使能量转移体系的RB的荧光强度降低,即发生猝灭.以此建立了利用AO-RB能量转移荧光猝灭法测... 相似文献
16.
在H2SO4介质中,KIO4氧化吖啶黄,使体系褪色并伴随荧光猝灭,痕量的As(Ⅲ)能显著阻抑此反应,据此建立了一种新的荧光法测定痕量As(Ⅲ)。本文对该体系的实验条件进行了详细研究。在最佳条件下,方法的线性范围为5.0~400μg/L,检出限为2.4μg/L。方法已用于环境水样中痕量As(Ⅲ)的测定,加标回收率为94.2%~102.6%。 相似文献
17.
研究了在pH5.0~6.4的HAC-NaAC缓冲介质中和CTMAB存在下,Mo(Ⅳ)对二甲氧基羟基苯基荧光酮(DMH-PF)的荧光猝灭效应,建立了荧光猝灭法测定微量Mo(Ⅳ)的新体系,DMH-PF最大激发波长为λex=514nm、最大发射波长为λem=547nm,DMH-PF与Mo(Ⅵ)形成1:2配合物使荧光猝灭,荧光猝灭量与Mo(Ⅵ)在0~0.072mg/L范围内呈线性关系,方法的检出限为0.0022mg/L,体系稳定,灵敏度高,采用液膜分离富集钼,可应用于合金钢和石墨中微量钼的测定。 相似文献
18.
荧光动力学分析法常以罗丹明类、荧光素类、桑色素等作为指示物,用蒽醌作为指示物较少见。本文报道了以2,3二-氢-9,10二-羟基-1,4蒽-醌(R)为指示物,荧光动力学分析法测定痕量汞的新方法。直接用硼酸代替三氯化铝加硫酸封环一步法制得1,4二-羟基-9,10蒽-醌,再经冰醋酸和锌粉还原 相似文献
19.
In this report we described a highly selective and sensitive iodate sensor. Due to its interaction with fluorescent gold nanoclusters, iodate was capable of oxidizing and etching gold core of the nanoclusters, resulting in fluorescence quenching. Furthermore, it was found that extra iodide ion could enhance this etching process, and even a small amount of iodate could lead to significant quenching. Under an optimized condition, linear relationship between the iodate concentration and the fluorescence quenching was obtained in the range 10 nM–1 μM. The developed iodate sensor was found selective and capable of detecting iodate as low as 2.8 nM. The sensor was then applied for the analysis of iodate in real sample and satisfactory recoveries were obtained. 相似文献
20.
A sensitive method for the detection of catecholamine based on the fluorescence quenching of CdSe nanocrystals was developed. The sodium citrate-protected CdSe nanocrystals were synthesized in water solution. The fluorescence quenching of CdSe nanocrystals by dopamine, uric acid, ascorbic acid and catechol was studied; the results showed that all of these four kinds of compounds could quench the fluorescence of nanocrystals, and the quenching constant was 6.3 × 10 4, 2.57 × 10 3, 2.14 × 10 3 and 1.168 × 10 3, respectively. The order of sensitivity for the biosensor was: dopamine > lactic acid > ascorbic acid > catechol. This method shows good selectivity for dopamine, the detection limit reaches 5.8 × 10 −8 M. 相似文献
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