水杨基萤光酮荧光熄灭法测定微量钛

本文用荧光熄灭法研究了水杨基萤光酮(SAF)-吐温-80-Ti(Ⅳ)体系的测定方法及条件。在pH1.0～2.0间的盐酸介质中,检测限为0.1μg/25ml,且在0.1～2.0μg/25ml范围内具有线性关系。本法灵敏度高,选择性好,可用于检测合金钢及铝合金中的微量钛,结果满意。     

A Fluorescence Quenching Method for the Determination of Iodide Ion with Salicylfluorone and Hydrogen Peroxide

Abstract

A highly sensitive and selective fluorescence quenching method has been developed for rapid determination of iodide ion with salicylfluorone (SAF) as fluorogenic reagent (λ_ex = 495 nm, λ_em = 520 nm) at pH 2.5-3.0. The calibration graph is linear over the range 0.05-300 μg/25 ml. The detection limit is 0.05 μ/25 ml iodide. Other halide ions do not interfere with the determination even when present in large excess. The method is rapid and was successfully applied for the determination of iodide ion in sodium chloride, table salt and low sodium salt.     

水杨基萤光酮荧光熄灭法测定微量钨

本文用荧光熄灭法研究了水杨基荧光酮(SAF)-溴化十六烷基三甲胺(CTMAB)-W(VI)体系的测定方法及条件。在pH1.2～3.5的硫酸介质中,检测限为0.1μg/25ml,在0.1～2.5μg/25ml范围内具有线性关系。本法灵敏度高,选择性好,用于检测合金钢中钨,结果满意。     

A Fluorescence Quenching Method for the Determination of Bromate Ion with 4,5-Dibromophenylfluorone and Cetyltrimethylammonium Bromide

Abstract

A highly sensitive and selective fluorescence quenching method was developed to determine the bromate ion (BrO₃ ^?) with 4,5-dibromophenylfluorone (DB-PF) as fluorogenic reagent. BrO₃ ^? reacts with potassium bromide in sulfuric acid solution (0.6M) giving bromine (Br₂) which is estimated with fluorescence quenching method using DB-PF as fluorogenic reagent. Bromine reacts with DB-PF to produce a compound, whose maximum excitation wavelength and emission wavelength are 543nm, 560nm respectively. The linear calibration range is 0.05–0.5 μg/25ml. The detection limit is 0.05μg/25ml. The method may be used to determine microamounts of BrO₃ ^? in potassium chlorate with satisfactory results. The method offers the advantages of simplicity, rapidity and sensitivity.     

4,5-二溴苯基萤光酮-溴化十六烷基三甲基铵——荧光光度法测定微量铌

本文研究了二溴苯基萤光酮-表面活性剂-铌三元体系的荧光特性,提出了以二溴苯基萤光酮-溴化十六烷基三甲基铵荧光光度法测定铌的新方法,该方法选择性和灵敏度以及重现性均很好,在λ_(ex)=420nm,λ_(em)=470 nm处铌含量在0～6μg/25ml范围内,线性关系良好、采用适当的掩蔽剂测定钢样中的微量铌,获得了满意的结果。     

协同系数补偿—动力学两次标准加入法测定相互干扰的双组份

本提出了协同铲应补偿的动力两次标准加入法，讨论了相互干扰双组份同时测定的原理，研究了钙（Ⅵ）和钨（Ⅵ）催化的Ｈ２Ｏ２－Ｉ＾－动力学反应，确定了同时测定条件：［Ｈ２Ｏ２］＝９．×１０＾－３ｍｏｌ／Ｌ，［Ｉ＾－］＝１．０×１０ｍｏｌ／Ｌ，ＰＨ３．０，２５℃；为补偿钼和钨之间的协同催化效化效应，引入了协同催化系数的概念，有效地消除了吸江度对加和性的偏离。用本法同时测定样品中的钼和钨含量，回收率分别为９     

二氯荧光素-氯化十六烷基吡啶荧光猝灭法测定微量碘

本文研究了用二氯荧光素(DCF)-氯化十六烷基毗啶(CPC)体系荧光猝灭法测定微量碘。在pH为2.8～3.1的H_2SO_4介质中,检出限为0.30μg/25ml,线性范围为0.30～2.00μg/25ml。本法灵敏度高,选择性好,适用于微量碘的测定。     

停流—荧光动力学分析法测定痕量钛的研究

利用自行组装的停流-荧光动力学分析仪,采用停流法汇合流体动力注入技术,研究了钛与3.5-二溴水杨基荧光酮的荧光增强动力学反应性质,讨论了流速、进样时间对方法灵敏度和精密度的影响,提出了一个快速、简便、精确测定钛的分析方法,并用于稀土样品及合成样品中痕量钛的测定.方法检测限为8×10~(-3)ppm,大多数元素的干扰均可用动力学方法消除.     

筛选抗癌药物的荧光实验法

筛选抗癌药物常用的体外肿瘤系统方法有甲烯蓝法、染色法、细胞呼吸法等,这些方法需要取肿瘤细胞进行实验,时间较长。顺铂是很好的抗癌药物,Sohell等用DNA-溴化乙啶(EthBr)荧光体系研究了铂络合物与DNA的作用,认为该体系可以半定量地说明铂络合物的抗癌性。本文研究发现一些络合物-DNA-EthBr体系的荧光大小与络合物的抗癌性有关,可用荧光法筛选抗癌药物。其可靠性远比甲烯蓝法高,方法简单、快速,且假阳性少。     

Fluorescence Quenching Method for Determination of Trace Tungsten in Soil after Cloud Point Extraction

A new procedure for trace tungsten W(VI) in soil by fluorescence quenching method coupled with cloud point extraction (CPE) as the separation-preconcentration method was described. The Triton X-100 CPE behavior of W(VI)-salicylfluorone (SAF)was investigated. Under the optimized conditions, the fluorescence quenched intensity (ΔF) was linearly with W(VI). The range of linear was 0.8 ～ 20.0 μg · L^?1, the detection limit (DL) was 0.14 ng · mL^?1 (3σ), the relative standard deviation 3.3% (c = 10.0 μg · L^?1, n = 5) and the recovery was 101.0–102.2%. The proposed method applied to the analysis of W(VI) in certified reference materials and real samples.     

荧光共振能量转移猝灭法测定片剂中莫西沙星含量

基于在pH 6.50的B-R缓冲溶液,十二烷基硫酸钠(SDS)介质中,吖啶橙(AO)-罗丹明B(RB)能够发生有效的能量转移,使RB荧光增强,而加入莫西沙星(MXFC)后使得RB的荧光猝灭,且其荧光淬灭程度与莫西沙星的质量浓度在1.00～10.0mg.L-1范围内呈线性关系,据此提出了利用AO-RB荧光共振能量转移,荧光淬灭法间接测定片剂中莫西沙星含量的方法。方法的检出限(3S/N)为0.039mg.L-1。方法用于莫西沙星片剂的分析,测定值与高效液相色谱法测定值相一致,加标平均回收率为99%,相对标准偏差(n=5)均小于0.9%。     

四(4-三甲铵苯基)卟啉荧光熄灭法测定痕量镉(Ⅱ)

利用TPPS₄催化动力学荧光测定痕量镉(Ⅱ)已有报道^[1],而利用四(4-三甲铵苯基)卟啉(TAPP)的荧光熄灭测定痕量镉(Ⅱ)的工作尚未见报道.本文研究了室温下Cd(Ⅱ)-TAPP反应体系的荧光光谱特性,发现Cd(Ⅱ)-TAPP的形成使TAPP的荧光发生静态熄灭.利用咪唑(Imid)、十二烷基硫酸钠(SDS)和乙醇增敏、增稳,最低可检测3×10^-4ppmCd(Ⅱ),灵敏度高于其它方法^[2].测定了胶印锌片和人发中的镉,结果与标准值或方法对照值吻合.     

荧光各向异性法快速测定荧光标记物对蛋白质的标记比

免疫荧光技术是免疫学检测的重要手段之一,该技术在病原微生物的早期诊断、自身免疫研究、抗原或抗体的免疫组化定位等方面都得到了广泛应用^[1].荧光色素对抗体(或抗原)标记比的测定是免疫荧光技术的重要部分.     

功能性CdS纳米荧光探针荧光增敏法测定人血清白蛋白

目前 ,以荧光分析法对蛋白质进行研究主要采用有机荧光探针[1～ 3 ] .与传统的有机染料 (如罗丹明 )探针相比 ,半导体纳米晶体探针的光强度要高 2 0倍 ,光稳定性要高 1 0 0倍 ,谱线宽度只是有机染料谱线宽度的 1 /3 [4 ] .将半导体纳米晶体作为探针用于测定生物分子 ,将大大提高分析的灵敏度和选择性 ,而目前其应用于生物染色、医疗诊断、DNA序列测定和免疫分析等方面的研究很少 [4 ,5] .本文合成了胶态纳米粒子 Cd S,并在其外表面修饰一层巯基乙酸 ,使其具有水溶性 ,并能与生物分子作用 ,从而可利用其外表面的功能性基团对人血清白蛋白进…     

卤代荧光素荧光猝灭法测定肾上腺色腙

在pH=6.6 的缓冲介质中, 肾上腺色腙(CBZC)与二氯荧光素(DCF)、二溴荧光素(DBF) 和二碘荧光素(DIF)通过静电引力、芳基堆积作用和范德华力形成摩尔比为2: 1的复合物, 引起上述二卤代荧光素的荧光发生猝灭, 最大猝灭波长分别位于533, 536和560 nm. 其荧光猝灭值(ΔF)在一定范围内与肾上腺色腙浓度成正比, 荧光猝灭反应具有较高的灵敏度, 对CBZC的检出限分别为3.3 ng/mL(CBZC-DCF体系), 5.7 ng/mL(CBZC-DBF体系)和129.6 ng/mL(CBZC-DIF体系). 考察了共存物质的影响、荧光猝灭反应的适宜条件和影响因素, 结果表明, 该方法具有良好的选择性, 可用于CBZC的血药和尿药浓度的快速检测. 从温度的影响、荧光寿命以及Stern-Volmer图判断该反应为静态猝灭反应.     

以TritonX-100为增敏剂荧光速率法测定银

基于醋酸钠介质中，银（Ⅰ）催化过硫酸钾氧化荧光素反应，以２，２－联吡啶为活化剂，Ｔｒｉｔｏｎ Ｘ－１００为增敏剂，拟定了测定痕量银的新荧光速率法。本法由于添加 Ｔｒｉｔｏｎ Ｘ－１００表面活性剂，使得灵敏度提高了４倍，测定银含量线性范围为２～３２ μｇ／Ｌ，相对标准偏差为３．１％（ｎ＝９），检出限为１．７６ × １０－３（ｍｇ／Ｌ）。用于测定氯化银的溶度积和光谱感光板中的银，结果满意。     

A Novel Method for Uric Acid Determination Using CdS Quantum Dots as Fluorescence Probes

A novel method has been developed for uric acid analysis based on the quenching of fluorescence emission from CdS quantum dots by uric acid. Also, the effect of the presence of different surfactant agents, in order to improve the fluorescent signals of the CdS QDs, has been investigated, and the cetyltrimethyl ammonium bromide (CTAB) was selected. Under optimum conditions, the calibration graph was linear over the range of 0.1 ng/mL to 12.0 ng/mL (r = 0.9950). The limit of detection (S/N = 3) was 0.1 ng/mL. The RSD for ten determinations of 5.0 ng/mL uric acid was 3.5%. The method was applied to determine uric acid in human serum and urine sample with satisfactory results.