流动注射-抑制化学发光法测定克百威

基于在碱性介质中,克百威抑制鲁米诺-过氧化氢-叶绿素铜钠体系的化学发光,提出了流动注射-抑制化学发光法测定克百威含量的方法。试验结果表明:叶绿素铜钠对克百威荧光猝灭过程是静态猝灭过程,叶绿素铜钠与克百威结合形成物质的量比为1比1的稳定配合物,平衡常数(K0)为3.41×105L.mol-1(25℃),结合距离(r)为0.39 nm。克百威质量浓度在0.08～2.00 mg.L-1范围内与其发光强度呈线性关系,方法检出限(3σ/k)为0.03 mg.L-1。此法用于克百威杀虫剂样品的分析,测得方法的平均加标回收率为101.5%。     

流动注射化学发光法检测水相中溶解臭氧浓度

基于碱性水溶液中臭氧氧化鲁米诺产生化学发光的现象,建立了利用流动注射化学发光技术检测水体溶解臭氧(DO3)的方法。检测了较高和较低两部分的DO3浓度范围,低浓度DO3从20μg/L到65μg/L,工作曲线为y=27．658In(X)-192．75;检出限为8．5μg/L(7次空白信号检测);高浓度D03从0．089mg／L到0．890mg／L,线性关系为y=0．0018x-23．711。溶液中的。DO3由靛蓝二磺酸钠法确定。随后利用化学发光系统检测鼓人臭氧气体的自来水,由工作曲线可以确定自来水中DO3的量。方法简便,结果准确。     

鲁米诺化学发光抑制法测定阿洛酮糖

建立一种流动注射化学发光测定阿洛酮糖的方法。基于碱性条件下,阿洛酮糖对鲁米诺-H₂O₂体系的发光强度具有显著的抑制作用,且发光信号的降低值(即相对发光强度)ΔI与阿洛酮糖浓度的对数在一定范围内成线性关系,建立了一种流动注射化学发光法测定阿洛酮糖的新方法。在最佳实验条件下,方法的线性范围为在0.002 mg·mL^-1～2.0 mg·mL^-1(R=0.9977),方法的检出限为4.3×10^-4 mg·mL^-1,对0.05 mg·mL^-1的阿洛酮糖连续测定11次,其相对标准偏差为3.1%。该方法用于果冻中阿洛酮糖含量的测定,与高效液相色谱法测得结果基本一致。     

流动注射-抑制化学发光法测定岩白菜素

本文基于岩白菜素对鲁米诺-牛血清白蛋白体系化学发光信号显著的抑制作用,建立了快速灵敏测定岩白菜素的流动注射-化学发光分析新方法。实验发现,化学发光强度的降低值与岩白菜素质量浓度对数值呈良好的线性关系,方法的线性范围为3.0~5.0×10~5 pg/mL,检出限(3σ)为1.0pg/mL。当溶液流速为2.0mL/min时,完成一次分析过程仅需30s,采样频率120/h。本法用于片剂、人血清和尿液中岩白菜素的含量测定,回收率为98.1%~102.7%,相对标准偏差小于2.0%(n=7)。同时对化学发光反应机理进行了探讨。     

流动注射-化学发光测定环境样品中的痕量铜

本文基于Cu2+与贮备铁氰化钾及鲁米诺在碱性条件下产生化学发光的原理,建立了一种新的测定痕量铜的化学发光方法。方法的相对标准偏差小于5.0%,线性范围为5.0×10-9～1.0×10-7mol/L,检出限(S/N=3)为8.0×10-10mol/L。用本法成功地实现了对环境样品中痕量铜的定量分析。     

儿茶酚胺类药物的流动注射化学发光分析

观察到雷盐（ＮＨ４「Ｃｒ（ＮＨ３）２」（ＳＣＮ）４」。Ｈ２Ｏ）对鲁米诺－Ｈ２Ｏ２化学发光反应的催化作用。根据儿茶酚胺类物质可与雷氏盐发生沉积反应而导致鲁米诺－Ｈ２Ｏ－２雷氏盐体系化学发光强度降低的性质，建立了儿茶酚胺类物质多巴胺，肾上腺素和异丙肾上腺素的流动注射化学发光分析法。     

纳米银参与的多潘立酮化学发光分析法研究

在碱性介质中,基于多潘立酮对纳米银(AgNPs)增敏Luminol-KMnO4化学发光体系发光信号的抑制作用,结合流动注射技术,提出了测定多潘立酮的化学发光分析新方法。在选定的流路和实验条件下,该方法测定多潘立酮的线性范围为1.0×10-8~5.0×10-6 g/mL,检出限为1.05×10-9 g/mL。对1.0×10-6 g/mL的多潘立酮溶液平行测定11次,其相对标准偏差(RSD)为1.7%。该法灵敏、准确、快速,用于样品中多潘立酮的测定,结果满意。     

流动注射-抑制化学发光法测定镱(Ⅲ)

在碱性介质中, Yb(Ⅲ)对Luminol-KMnO4体系化学发光强度具有抑制作用, 据此建立了一种测定Yb(Ⅲ)的化学发光新方法. 在优化的实验条件下, 化学发光强度与Yb(Ⅲ)的浓度在4.0×10-7～1.0×10-4 mol/L范围内呈现出良好的线性关系. 其检测限(3σ)为5.0×10-8 mol/L, 对8.0×10-5 mol/L的Yb(Ⅲ)溶液进行测定, 相对标准偏差为3.9% (n=11). 本法已应用于合成样品中的镱的测定.     

空气中肼的流动注射化学发光分析

研究了肼在碱性条件下与鲁米诺和高磺酸钾产生化学发光行为，建立了流动注射化学发光测定痕量肼的新方法。肼的浓度在１．０×１０＾－８－１．０×１０＾－６ｇ／ｍＬ范围内与化学光强度成线性关系；检出限为４×１０＾－９ｇ／ｍＬ；相对标准偏差小于３％。     

流动注射速差动力学化学发光分析Ⅱ微量磷的快速测定

本文根据磷钼杂多酸可直接氧化Ｌｕｍｉｎｏｌ产生化学发光的特性，建立了磷的流动注射化学发光分析方法。利用磷钼杂多酸、硅钼杂多酸、砷钼杂多酸形成速率的差异，在磷、硅、砷共存时，可不经任何分离，实现对水样和钢样中磷的快速测定。该法检出限为３．６×１０－５ｇ／Ｌ，线性范围２．０×１０－４～１．０×１０－２ｇ／Ｌ，相对标准偏差为１．８％（磷浓度１．０×１０－３ｇ／Ｌ；ｎ＝１１次）。采样频率４５样／ｈ。     

流动注射电化学发光分析法测定甲磺酸培氟沙星

甲磺酸培氟沙星为第三代喹诺酮类抗菌药,疗效好,抗菌谱更广,且对青霉素、头孢菌素、氨基苷类耐药菌株均有效,在临床上被广泛使用。本文发现,在Na2CO3-NaHCO3碱性溶液中,1．40V电解电位下,鲁米诺在铂电极上的弱电化学发光信号可以被甲磺酸培氟沙星强烈地增敏,据此建立了甲磺酸培氟沙星的流动注射电化学发光分析方法。     

Determination of norfloxacin in pharmaceuticals,human serum,and urine using a luminol—dissolved oxygen chemiluminescence system

A sensitive chemiluminescence method, based on the enhancive effect of norfloxacin on the reaction between luminol and dissolved oxygen in a flow injection system, was proposed for the determination of norfloxacin. The increment of the chemiluminiscence intensity was proportional to the concentration of norfloxacin, giving a calibration graph linear over the concentration from 0.4 ng mL⁻¹ to 400.0 ng mL⁻¹ (r ² = 0.9988) with the detection limit of 0.1 ng mL⁻¹ (3 × σ _noise). At the flow rate of 2.0 mL min⁻¹, a complete determination of norfloxacin, including sampling and washing, could be accomplished in 30 s with the relative standard deviation lower than 3.0 %. The proposed method was applied successfully to determine norfloxacin in pharmaceuticals, human urine, and serum. Possible mechanism of the reaction was also discussed.     

Spectrofluorimetric determination of carbaryl and 1-naphthol in micellar media

The interaction of 1-naphthol-N-methyl-carbamate (carbaryl) and its degradation product, 1-naphthol, with the surfactant hexadecyl-trimethylammonium bromide has been studied. The micellar medium allows the direct spectrofluorimetric determination of carbaryl, with 6.2 ng/ml as detection limit in acidic medium, or indirectly, after hydrolysis, as 1-naphthol at pH 11.0 or pH 3.0 with detection limits of 0.4 and 1.6 ng/ml, respectively. The recoveries of carbaryl and 1-naphthol from natural waters are acceptable.     

Flow-injection chemiluminescence method for determination of critical micelle concentration of surfactants

In this study, chemiluminescence (CL) behaviour of Luminol-H₂O₂ in the presence of the different concentrations of four surfactants, cetyltrimethylammonium bromide (CTAB), cetylpyridinium bromide (CPB), sodium dodecyl sulphate (SDS) and polyoxyethylene dodecyl ether (Brij-35), was investigated. A novel method for the direct determination of critical micelle concentration (CMC) of the surfactants using flow-injection CL is described. Under the optimum conditions, the luminescence intensity of the Luminol-H₂O₂ system increased gradually with increasing concentration of the surfactants before the CMC, but rapidly reached to the emission maximum at the CMC, followed by a decrease after the CMC. The concentrations of the surfactants corresponding to the luminescence maximum are in agreement with the literature CMC values. The main factors affecting the determination of CMC are discussed. The mechanistic studies show that the luminescence peaks observed in the experiment were mainly because of the protective effect of the micelle against the transition of the excited species and the retarding effect of the micelle structures on the CL reaction rate.     

Simultaneous kinetic determination of chlorpyrifos and carbaryl based on differential degradation processes in alkaline oxidative medium

A kinetic method for the simultaneous determination of chlorpyrifos and carbaryl is described. The method is based on the degradation of these compounds in alkaline hydrogen peroxide medium by measuring the absorbance at two different reaction times and at two different wavelengths. A homemade stopped-flow system coupled with a diode-array detector and the proportional equation method was used. Resolution was achieved over chlorpyrifos: carbaryl ratios ranging from 61 to 14, with relative errors of 4 and 3%, respectively. The method was successfully applied to the analysis of a commercial formulation.     

流动注射化学发光法测定样品中的白藜芦醇

白藜芦醇具有抗菌、抗氧化、抗衰老、抗癌的作用[1-2],能阻碍血小板凝聚、调节血脂,防止低密度脂蛋白氧化,能抑制生物体内过氧化作用,能消除自由基。植物体内的白藜芦醇作为一种植物抗毒素而存在,其结构同己烯雌酚,有雌激素作用。白藜芦醇在虎杖,花生,葡萄,桑椹中含量最高,白藜     

Flow-injection determination of total iron in freshwater samples with neutralisation chemiluminescence

A flow-injection chemiluminescence method has been established for the determination of total iron in freshwater samples. The enhanced chemiluminescence emission was caused by the iron(II) from the neutralisation reaction of hydrochloric acid and sodium hydroxide without the use of any chemiluminescent reagent. The calibration graph was linear in the concentration range of 2.8–560 µg L^?1 (r ² = 0.9983, n = 8), with relative standard deviation (RSD; n = 4) in the range of 0.8–2.6%. The limit of detection (S/N = 3) was 0.56 µg L^?1 with injection throughput of 180 h^?1. The effect of common anions and cations were studied over their environmentally relevant concentrations in freshwaters. The method was successfully applied to determine total iron in freshwater samples. Iron(III) was reduced to iron(II) by using hydroxylammonium chloride. The proposed method was compared with spectrophotometric method and there was no significant difference between the two methods at the 95% confidence level (t-test). Analysis of river water (certified reference material SLRS-4) for iron(II), after reduction of iron(III) with hydroxylammonium chloride, gave good results (2.17 ± 0.22 µM compared with the certificate value of 1.85 ± 0.1 µM).     

Simultaneous voltammetric determination of carbendazim and carbaryl in medicinal plant infusions with a boron-doped diamond electrode

This study is aimed to develop an electroanalytical methodology using a boron-doped diamond electrode to determine simultaneously and selectively carbendazim (CBZ) and carbaryl (CAR). In previous studies using cyclic voltammetry oxidation, peaks were observed at 1.03 V (CBZ) and 1.44 V (CAR), with characteristics of an irreversible process controlled by diffusion of species, with a supporting electrolyte of BR buffer (0.1 mol L^?1) and pH adjusted to 6.0. The differences between the potentials for both pesticides, about 400 mV, indicate the possibility of selective determination of CBZ and CAR. The square-wave voltammetric parameters were optimised. The best separation conditions were pH 6.0, square-wave frequency of 100 s^?1, pulse amplitude of 50 mV and scan increment of 2.0 mV. These parameters were used to obtain the calibration curves of CBZ and CAR. An analytical curve was constructed in the range concentration of CBZ of 1.3 mg L^?1 to 15.3 mg L^?1 and CAR of 1.0 mg L^?1 to 11.4 mg L^?1, respectively. The limits of detection (LOD) and limits of quantification (LOQ) for CBZ were 0.40 mg L^?1 and 1.30 mg L^?1, respectively. For CAR, the LOD and LOQ were 0.30 mg L^?1 and 1.00 mg L^?1, respectively. Sensitivity values were 0.78 and 2.60 µA/mg L^?1 for CBZ and CAR, respectively. The electroanalytical method was applied in Mikania glomerata infusions. The recovery values were 106.2% and 116.5% for CBZ and CAR, respectively. The results show that the developed method is suitable for application in medicinal plant samples.     

A Highly Sensitive and Selective Assay for Cysteine Using the Chemiluminescence Reaction of Luminol and Hydrogen Peroxide

A very simple, highly sensitive and selective chemiluminescence (CL) method was established for the determination of cysteine. This method is based on the fact that the CL reaction of luminol and hydrogen peroxide can be greatly enhanced by cysteine. The CL intensities at maximum light emission were linearly correlated with the concentration of cysteine over the range of 2.0×10^–8–6.0×10^–6molL^–1 with a detection limit of 7.5×10^–9molL^–1. The relative standard deviation was 1.7% for the determination of 1.0×10^–7molL^–1 cysteine (n=9). The feasibility of utilizing the proposed method for the determination of total concentration of cysteine in human serum was examined.     

微分析系统对苯二酚抑制化学发光的研究

在自行设计和制作的有机玻璃 (PMMA)微流控芯片上 ,以流动注射方式进样 ,利用对苯二酚对Luminol H2 O2 Co2 +体系化学发光 (CL)的强抑制作用 ,建立了间接测定对苯二酚含量的微型全化学分析系统 ( μ TAS)。对影响化学发光反应的各因素进行优化 ,对芯片结构的设计和反应过程进行探讨 ,设计并制作出适合该反应体系的芯片。在合成水样对苯二酚的测定中 ,化学发光强度的变化与对苯二酚的浓度在 1 .0× 1 0 - 7～ 2 .0× 1 0 - 8mol/L范围内成良好线性关系 ,检出限达 2 .0× 1 0 - 9mol/L。