人工神经网络X射线荧光光谱法测定钢中酸溶铝

建立了一种人工神经网络-X射线荧光光谱法测定钢中酸溶铝的方法，用X射线荧光光谱法测定低合金钢中总铝值，应用所建立的ANN-BP网络模型，输入总铝含量直接预测出酸溶铝含量。同时使用改进的BP算法，避免了神经网络学习中可能产生的麻痹现象。该方法用于钢中酸溶铝的测定，结果满意。     

以四硝基铝酞菁为荧光探针测定葡萄糖的荧光分析新方法

建立以四硝基铝酞菁为荧光探针测定葡萄糖的荧光分析新方法。方法基于四硝基铝酞菁苯环上的硝基与葡萄糖发生还原反应,形成铝酞菁的氨基化产物;氨基化铝酞菁具有红区激发和发射的特性,在强酸性介质中可发射较强荧光;体系的荧光强度和葡萄糖的含量呈良好的线性关系,并具有较好的准确性和稳定性。方法用于测定发酵样品中的还原糖,结果满意。     

9-(3，5-二溴)水杨基荧光酮-溴化十六烷基三甲铵荧光光度法测定微量铝

研究了９－（３,５－二溴）水杨基荧光酮与铝（Ⅲ）的反应条件。在ＰＨ５．５的（ＣＨ２）６Ｎ４－ＨＣＬ缓冲溶液中,ＡＩ（Ⅲ）与试睡成络合物使试剂的荧光猝灭。建立了铝－９－（３,５－二溴）,水杨基荧光酮体系测定痕量铝的荧光光度法。荧光强度与铝的含量在０～１．４μｇ／ｍＬ范围内呈线性关系。本法已用于合金风标样中铝的测定。     

氧氟沙星-铝(Ⅲ)-十二烷基苯磺酸钠荧光体系测定氧氟沙星的研究

在表面活性剂十二烷基苯磺酸钠(SDBS)存在下,氧氟沙星能与铝(Ⅲ)形成络合物而使氧氟沙星的内源性荧光显著增强,提出了氧氟沙星-铝(Ⅲ)-十二烷基苯磺酸钠(SDBS)荧光体系测定氧氟沙星含量的新方法。氧氟沙星在1.0×10-9~2.0×10-7kg/L范围内,与荧光增敏值成良好的线性关系,方法检出限为5.0×10-10kg/L。该方法简单,灵敏度高,选择性好,可直接用于片剂和注射液中氧氟沙星含量的测定。     

铬天青S分光光度法测定食品中铝

<正>铝是地壳中含量位居第三的元素,广泛分布于自然界中,在一些植物本底中含量很高~([1])。另外由于传统工艺的运用,某类食物中的铝含量也较高。纵观各种关于食品中铝毒性的报道可知,近几年开展的食品污染物风险监测选择膨化食品、面制食品、米粉和海蜇等进行铝的测定是非常及时和必要的。目前测定铝的方法有分光光度法、荧光光谱法、原子吸收光谱法和等离子体原子发射光谱法~([2])等。本工作采用微波消解处理食品样品,铬天青S     

铝-荧光镓极谱络合吸附波的研究

在ｐＨ５．７２的缓冲溶液中,用单扫示波极谱法可获得灵敏的铝－荧光镓络合吸附波。检测限达１．０×１０＾－８ｍｏｌ／Ｌ。测定了自来水中铝的含量,并测定了络合物组成和表面电极反应速度常数。     

顺序注射荧光光度法测定茶叶中的铝

20世纪70年代临床研究发现铝与老年性痴呆症,帕金森氏痴呆综合症等神经系统疾病相关以来,铝的生物毒性引起人们的广泛关注.铝的测定在食品和环境科学及生物医学研究中具有重要意义.本文基于铝与8-羟基喹啉-5磺酸在酸性介质中的产物的荧光性质,以十六烷基三甲基溴化铵为增敏剂,将顺序注射进样与荧光检测技术联用,建立了铝的顺序注射荧光分析法.方法具有快速、简单、精密的优点,线性范围为3.0～350 μg/L, 检出限为0.6 μg/L,分析方法的RSD小于1%.单次测定仅消耗试剂0.12 mL,试样0.35 mL,茶叶中的铝含量的测定结果与标准值一致.     

中成药中铝含量的光度法测定

研究了二溴羟基苯基荧光酮与铝的显色体系。在Tween-80及F-存在下,铝与二溴羟基苯基荧光酮在碱性介质中形成1∶2的玫瑰红色四元配合物,最大吸收波长558 nm,摩尔吸光系数1.5×105L.mol-1.cm-1,铝含量在0~0.24μg/mL符合比尔定律。方法灵敏,选择性好,用于中成药中微量铝的测定取得满意结果。     

SAAQ-CTMAB荧光光度法测定微量铝的研究

某些席夫碱具有一定的刚性平面及富电子的共轭体系 ,从而使其显示出良好的荧光特性 ,导致该类试剂在荧光分析中显出越来越重要的作用[1 ] 。虽然荧光法测定铝已有文献[2～4] 报道 ,但本文所提出的ＳＡＡＱ在ＣＴＭＡＢ存在下与铝产生荧光增敏测定微量铝的方法尚未见报道。研究表明在ｐＨ =4.0～ 5.5的乙酸铵缓冲溶液及ＣＴＭＡＢ存在下 ,铝与ＳＡＡＱ形成 1∶2的络合物。该络合物在λｅχ/λｅｍ=378ｎｍ/490ｎｍ处荧光最强 ,线性范围为 0～ 2 0 0 μｇ·ｄｍ- 3,方法用于人发及茶叶中铝含量的测定 ,结果满意。1　试验部分1 .1　仪器与试剂…     

铝—酸性铬蓝K荧光光度法测定微量铝的研究

研究了酸性铬蓝Ｋ（ＡＣＢＫ）荧光光度法测定微量铝的反应。Ａｌ＾３＋与ＡＣＢＫ形成络合物的荧光强度与铝的含量在１×１０＾－８～８×１０＾－６ｍｏｌ／Ｌ范围内呈现良好的线性关系，检测限为４．８×１０＾－９ｍｏｌ／Ｌ，对４×１０＾－８ｍｏｌ／Ｌ铝重复１１次检测其相对标准偏差为４．８％，成功地用于人发及钢样中铝含量的测定。     

A Fluorescence Synergistic Method for the Determination of Stilboestrol

Abstract

A simple, highly sensitive and selective fluorescence synergistic method has been developed for rapid determination of stilboestrol with Triton × — 100 (λ_ex = 318nm, λ_em = 415nm) at pH 8.80 ～ 10.20. The calibration graph is linear over the range of 0.0 ～ 30.0μg/10ml. The detection limit is 0.03μg/ml stilboestrol. The method has been successfully applied for the determination of stilboestrol in tabellae stilboestrol and injectio stilboestrol with satisfactory results. It can also be applied for the determination of stilboestrol in body fluid of special patients.     

采用新型固相萃取柱快速测定食用植物油中苯并［a］芘

研究了Bond Elut ENV新型固相萃取柱在食用植物油中苯并[a]芘快速检测中的应用,建立了快速测定食用植物油样品中苯并[a]芘残留量的固相萃取/液相色谱/荧光检测法。样品用正己烷溶解,固相萃取净化,SUPELCOSILTMLC-PAH(25 cm×4.6 mm,5μm)色谱柱分离,以乙腈-水(95∶5)为流动相,荧光检测(λex=297 nm,λem=408 nm),外标法定量。苯并[a]芘的检出限为0.3μg/kg,在1.0～50.0μg/L范围内线性关系良好,相关系数为0.999 6,方法的回收率为79%～102%,相对标准偏差不高于9.4%。该方法准确、实用、简便、快速,在食用植物油的苯并[a]芘残留量检测方面有广泛的应用前景。     

反相高效液相色谱法测定血浆中氢溴酸右美沙芬浓度

报道了反相高效液相色谱法测定血浆中氢溴酸右美沙芬 ( DM)方法。采用Novapak C84μm,1 5 0 mm× 3.9mm i.d.分析柱 ,以乙腈∶水 =5 0∶ 5 0 ( V/V ,加0 .5 % HAc,三乙胺调节 p H至 4.3)为流动相 ,荧光检测器检测 ,DM的最小检出浓度为 0 .2 ng/m L。方法回收率为 93.71 % ,变异系数 3.5 3% ,操作简便 ,灵敏度高 ,适于血浆中 DM测定及药代动力学研究     

[MeCl4]-型配阴离子-亚甲蓝离子缔合物的溶剂萃取和荧光法测定痕量亚甲蓝

研究了离子缔合物溶剂萃取的适宜条件、有机相中荧光和共振荧光光谱特征, 讨论了离子缔合物的组成和结构, 考察了有关的分析化学性质. 建立了测定痕量亚甲蓝的高灵敏度的方法, 其检出限分别为0.2和0.6 ng/mL(荧光法)以及1.1和2.8 ng/mL(共振荧光法), 荧光法具有更高的灵敏度, 更宜于痕量亚甲蓝的测定. 将该方法用于人血清和尿样中痕量亚甲蓝的测定, 结果较好.     

吖啶橙-罗丹明6G能量转移荧光法测定痕量磷

在λex/λem=450/556nm,十二烷基苯磺酸钠(DBS)存在下,吖啶橙-罗丹明6G能够能有效能量转移,使罗丹明6G荧光大大增强,酸性条件下,正酸根与钼酸钼反应生成磷钼酸,磷钼酸与R6G形成离子缔合物,使R6G的光猝来利用吖淀橙-罗丹明6G能量转变荧光法测定痕量磷,提高了测定磷的灵敏度和选择性,磷含量的0.05~0.70μg/L 范围内与罗丹明6G的荧光猝程度呈良好的线性关系.最低检出限为5ng/L,回收率为95%~110%,测定0.50μg/L,磷溶液,相对标偏差为6%,该法用于水样及土壤中的活性磷的测量,结果满意.     

Stopped-flow injection determination of copper(II) at the ng ml−1 level

A stopped-flow injection method for the determination of copper(II) in the range 0.2–300 ng ml^?1 is proposed, based on the catalytic effect of this ion on the 2,2'-dipyridylketone hydrazone/hydrogen peroxide reaction. The oxidation product shows an intense blue fluorescence that is monitored at λ_ex = 350 nm, λ_em = 427 nm. The sampling rate (72 h^?1), r.s.d. (1.4%) and the lack of interference from most foreign ions, allowed application of the method to the determination of copper in foods and blood serum.     

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.     

含有双发色团的化合物分子内能量传递的研究

合成了一系列含有萘环和蒽环的不同链长的二元化合物, 简写为N-Mn-A(n=2,4,6,8,10)。在有机溶剂中做了上述系列化合物的荧光光谱。激发波长为λex=280nm时, 发现荧光光谱中有两个发射峰, λem1=370nm, λem2=450nm。前者为萘的荧光峰, 后者为蒽的荧光峰。实验证明, 只有萘吸收280nm的光, 而蒽无吸收。所以在激发萘的条件下, 能量由处于激发态的萘环传向了外于基态的蒽环。在不同的有机溶剂中, 分别做了该系列化合物的荧光光谱随浓度的变化。实验结果指出, 两个荧光峰强度的比值不随浓度的变化而变化, 表明其能量传递为分子内的能量传递。另外在1%的糖淀粉水溶液中, N-Mn-A的浓度为1.0×10^-^5mol.dm^-^3,通过荧光光谱发现没有发生能量传递。表明处于伸展状态的N-Mn-A化合物分子不能发生能量传递。     

Kinetic-fluorimetric determination of cerium with 1-amino-4-hydroxyanthraquinone

A simple, sensitive, and selective method for the kinetic—fluorimetric determination of cerium (0.1–0.9 ppm), based on the oxidative reaction between cerium(IV) and 1-amino-4-hydroxyanthraquinone, has been developed. The reaction is followed by the measurement of the rate of appearance of yellow fluorescence (λ_ex = 480 nm, λ_em = 575 nm). About 20 cations and anions show negligible interference effects, even when present in large amounts. Only V(V) interferes at similar concentrations to those of Ce(IV) to be determined.     

Environment-sensitive fluorophores with benzothiadiazole and benzoselenadiazole structures as candidate components of a fluorescent polymeric thermometer

An environment-sensitive fluorophore can change its maximum emission wavelength (λ(em)), fluorescence quantum yield (Φ(f)), and fluorescence lifetime in response to the surrounding environment. We have developed two new intramolecular charge-transfer-type environment-sensitive fluorophores, DBThD-IA and DBSeD-IA, in which the oxygen atom of a well-established 2,1,3-benzoxadiazole environment-sensitive fluorophore, DBD-IA, has been replaced by a sulfur and selenium atom, respectively. DBThD-IA is highly fluorescent in n-hexane (Φ(f) =0.81, λ(em) =537?nm) with excitation at 449?nm, but is almost nonfluorescent in water (Φ(f) =0.037, λ(em) =616?nm), similarly to DBD-IA (Φ(f) =0.91, λ(em) =520?nm in n-hexane; Φ(f) =0.027, λ(em) =616?nm in water). A similar variation in fluorescence properties was also observed for DBSeD-IA (Φ(f) =0.24, λ(em) =591?nm in n-hexane; Φ(f) =0.0046, λ(em) =672?nm in water). An intensive study of the solvent effects on the fluorescence properties of these fluorophores revealed that both the polarity of the environment and hydrogen bonding with solvent molecules accelerate the nonradiative relaxation of the excited fluorophores. Time-resolved optoacoustic and phosphorescence measurements clarified that both intersystem crossing and internal conversion are involved in the nonradiative relaxation processes of DBThD-IA and DBSeD-IA. In addition, DBThD-IA exhibits a 10-fold higher photostability in aqueous solution than the original fluorophore DBD-IA, which allowed us to create a new robust molecular nanogel thermometer for intracellular thermometry.