鲁米诺-铁氰化钾化学发光体系测定氧氟沙星

基于氧氟沙星对鲁米诺-铁氰化钾化学发光体系具有较强的增敏作用,建立了一种测定氧氟沙星的新方法。该法简便、快速、灵敏度高,化学发光强度的变化值与氧氟沙星的浓度在6.84×10^-9—2.28×10^-5mol/L范围内呈线性关系,检出限（S/N=3）达4.56×10^-10mol/L。方法成功用于胶囊中氧氟沙星含量的测定,结果令人满意。     

鲁米诺-铁氰化钾化学发光体系测定利福平

基于鲁米诺在碱性条件下可以被铁氰化钾氧化产生化学发光,利福平对此化学发光具有增敏作用这一现象,结合流动注射技术建立了一种直接测定利福平的流动注射化学发光分析新方法.该方法的线性范围为5.0×10-8-3.0×10-6 g·mL-1,检出限为1×10-8g·mL-1,对3.0×10-7g·mL-1的利福平连续进行11次平行测定,其相对标准偏差为4.5%,该方法已成功地测定了利福平眼药水中利福平的含量.     

反相流动注射-化学发光法测定盐酸多巴胺

基于在碱性介质中,盐酸多巴胺对鲁米诺-铁氰化钾化学发光反应体系的强烈抑制作用,建立了反相流动注射抑制化学发光测定盐酸多巴胺的新方法。研究了影响化学发光强度的因素,并探讨了化学发光反应的可能机理。该方法快速、准确、线性范围宽,测定盐酸多巴胺的检出限为1.14×10-9 g·mL-1,方法的线性范围为2.0×10-9～8.0×10-7 g·mL-1,对于4.0×10-7 g·mL-1盐酸多巴胺测定11次的相对标准偏差为0.99%。应用于盐酸多巴胺注射液中盐酸多巴胺的测定,结果满意。     

鲁米诺-高锰酸钾流动注射化学发光体系测定头孢呋辛钠

在碱性介质中,鲁米诺与高锰酸钾反应产生化学发光,头孢呋辛钠能增强其化学发光强度,据此,建立了流动注射化学发光测定头孢呋辛钠的新方法。在最佳实验条件下,相对发光强度与头孢呋辛钠的质量浓度在2.0×10-7—8.0×10-5g/mL范围内,呈良好的线性关系,方法的检出限为3.0×10-8g/mL;对8.0×10-6g/mL头孢呋辛钠进行11次平行测定,相对标准偏差为1.1%。该方法用于合成样品及尿样的测定,结果满意。     

流动注射化学发光增强法测定焦性没食子酸

在较低 p H值的 Na OH介质中 ,焦性没食子酸对 Luminol- K3 Fe(CN) 6化学发光体系有很强的增敏作用 ,据此建立了焦性没食子酸的测定方法——流动注射化学发光增强法。该法的化学发光增强值 (ΔI)与焦性没食子酸浓度 (在 3.0× 10 -9— 1.0× 10 -6mol/ L范围内 )呈良好的线性关系 ,检出限为 1.0× 10 -9mol/ L(n=11) ,对 5× 10 -8mol/ L焦性没食子酸测定的相对标准偏差为 2 .8%。用于没食子酸热解产物中的焦性没食子酸测定 ,结果令人满意     

鲁米诺化学发光熄灭法测定稀土镧的研究

本文研究了稀土La（Ⅲ）对Luminol-H2O2-Cr(Ⅲ)化学发光体系的熄灭效应，在此基础上建立了稀土镧的流动注射化学发光分析法，方法的检出限为4×10^-8mol/L；对于2×10^-7mol/L稀土镧标准溶液测定的相对标准偏差为3.0%（n＝11）；线性范围为1.0×10^-7-1.0×10^-4mol/L；相关系数大于0.9984，该法用于合成样品分析，结果满意。     

化学发光分析法测定绿原酸

本文基于碱性介质中绿原酸对鲁米诺-铁氰化钾化学发光体系的抑制作用,首次建立了绿原酸的化学发光分析法,并探讨了其作用机理。方便简便、迅速、重复性好、灵敏度高。采用该法可测定1.0×10-8g/ml～1.0×10-5g/ml范围内的绿原酸,其检出限达到5.2×10-9g/ml,回收率为104%.     

鲁米诺化学发光猝灭法测定微量钬的研究

本文利用钬对鲁米诺-过氧化氢-铬(Ⅲ)体系化学发光的熄灭效应,建立了钬的流动注射化学发光分析法.该法灵敏度高、线性范围宽、仪器设备简单、操作方便.     

流动注射化学发光法测定头孢拉定

研究发现在碱性条件下,头孢拉定对鲁米诺化学发光体系有增敏作用,结合流动注射化学发光法建立测定头孢拉定含量的新方法,该法的线性范围为1.0×10-7—1.0×10-4g/mL,检出限(3σ)为8×1-0 8g/mL,对5.0×1-0 6g/mL头孢拉定样品连续进行11次平行测定,其相对标准偏差(RSD)为1.6%,该法可用于测定头孢拉定胶囊中头孢拉定的含量。     

流动注射化学发光法测定水中氰化物

基于流动注射化学发光分析和对 Luminol- Cu2 - CN-化学发光体系进行研究 ,建立了测定水中氰化物的分析方法。在其最佳实验条件下 ,测定 CN-的线性范围为 0 .0 0 2— 5μg/m L,检出限 0 .0 0 0 4μg/m L。对0 .0 5 0μg/m L CN-连续测定 7次 ,其相对标准偏差为 1.9%。     

Flow injection determination of metoclopramide based on KMnO4—HCHO chemiluminescence in a micellar medium

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.     

N-溴代丁二酰亚胺氧化体系流动注射化学发光法测定水中苯酚

在碱性介质中,N-溴代丁二酰亚胺氧化鲁米诺产生化学发光,苯酚对反应具有很强的抑制作用,据此建立了N-溴代丁二酰亚胺-鲁米诺-苯酚化学发光体系测定水中苯酚的新方法。当苯酚的浓度在1.0×10-5～9.0×10-4 mg·mL-1范围内,其浓度与发光强度呈良好的线性关系, 检出限是1.81×10-7 mg·mL-1, 相对标准偏差为1.11%, 将该方法直接用到水样中苯酚的测定, 取得满意的结果。并探讨了该化学发光反应的机理。     

A Sensitive Chemiluminescence Flow Injection Procedure for Assay of Fluoride in Waters and Humane Urine by Use of Immobilized Reagents

A new simple, rapid, selective and sensitive analytical procedure based on chemiluminescence (CL) detection is described for the determination of free fluoride at sub‐nanogram levels by use of controlled‐reagent‐release technology in a flow injection system. The analytical reagents involved in the CL reaction, including luminol and periodate, were both immobilized on anion‐exchange resins in a flow injection system. Through water injection luminol and periodate were eluted from the anion exchange column to generate the chemiluminescence, which was enhanced in the presence of fluoride. The increased CL intensity was linear with fluoride concentration in the range from 0.1 to 10 ng·mL^? 1. The limit of detection was 20 pg·mL^? 1 (3σ) and the relative standard deviation (RSD) was 1.02% (n = 5) for a 1.0 ng·mL^? 1 fluoride. At a flow rate of 2.0 mL·min^? 1, including sampling and washing, a typical analytical procedure could be performed in 0.5 min with a RSD of less than 3.0%. The proposed method was successfully applied to determine the free fluoride in water and human urine, and the results were in good agreement with those obtained by ion chromatography.     

A sonochemical assisted synthesis of hollow sphere structured tin (IV) oxide on graphene oxide sheets for the low-level detection of environmental pollutant mercury in biological samples and foodstuffs

In modern approaches for nanomaterials synthesis, ultrasonication plays an important role in providing the larger surface area and smaller crystalline size properties that are favorable to electrochemical techniques. Herein, we report the tin (IV) oxide on graphene oxide nanoparticles were synthesized (SnO₂@GO NPs) by ultrasonic methodology (UZ SONOPULS HD 3400 Ultrasonic homogenizer) with the total power of 400 W and the (frequency of 20 kHz; 140 W/dm³). The formation of as-prepared SnO₂@GO NPs and its surface morphology were scrutinized over XRD, XPS, TEM, and FESEM. Besides, the sonochemically prepared SnO₂@GO NPs were employed for the determination of environmental hazardous mercury (Hg). As a result, the modified electrode acquired a very low-level detection limit of 1.2 nM with a wider range of 0.01–10.41-µM and 14.52–225.4-µM for the detection of Hg. Finally, the practical applicability of SnO₂@GO NPs in spiked human blood serum and tuna fish samples shows appreciable found and recovery values..     

非分离状态下FI-KR-FAAS测定铁的价态

建立了流动注射(FI)编结反应器(KR)在线预富集与火焰原子吸收光谱(FAAS)联用非分离状态下测定铁的价态的新方法。进样流速6.0 mL.min-1;进样时间60s,测定0.04 mg.L-1的Fe(Ⅲ)和Fe(Ⅱ),Fe(Ⅲ)和Fe(Ⅱ)的浓集系数(EF)分别为41和9;检出限分别为2.5和14.3μg.L-1;相对标准偏差(RSD,n=11)分别为2.3%和3.1%。以0.1‰φ的三乙醇胺为掩蔽剂,Fe(Ⅲ)和Fe(Ⅱ)在水样中的回收率分别为97%～101%和96%～100%。     

两步洗脱法FIA-FAAS测定水样中的锌

建立了流动注射(FI)在线预富集与火焰原子吸收光谱(FAAS)联用测定水样中痕量锌的两步洗脱新方法。将洗脱和检测分成2个步骤进行。洗脱过程中,洗脱剂不经过蠕动泵管而是依靠蠕动泵的吸力通过聚四氟乙烯管(PTFE tube)进入编结反应器(KR),然后送入FAAS进行检测,大大延长了蠕动泵管的使用寿命。同时,洗脱过程依靠蠕动泵的吸力而不是推力实现洗脱剂的输送,明显降低了被分析物在洗脱过程中的分散,提高了原子吸收信号峰值(A)和浓集系数(EF)。增加了样品溶液排空步骤,保证了每次实验的准确性和重复性。进样流速6.0mL.min-1;进样时间60s,测定20μg.L-1的锌,EF由传统方法的9提高到28;检出限为0.35μg.L-1;测样频率为37.h-1;相对标准偏差(RSD,n=11)为2.1%。以0.1‰φ的三乙醇胺为掩蔽剂,在水样中的回收率为98.7%～99.6%。     

A method for the determination of residual beta activity in drinking water samples

The determination of residual beta activity in drinking water is usually needed in most monitoring programs. In this work a procedure for its determination is described and expressions for the calculations of detection limits and uncertainties are proposed.     

A nanostructure-based electrochemical sensor for square wave voltammetric determination of N-acetylcysteine in pharmaceutical and biological samples

Ionics - In this study, a carbon paste electrode (CPE) was chemically modified with Pt/carbon nanotubes (CNTs) nanocomposite and 8,9-dihydroxy-7-methyl-12H-benzothiazolo [2,3-b] quinazolin-12-one...     

FI-KR-FAAS空气混合吸附二次气体分隔洗脱法测定海洋生物样中的痕量铅

建立了流动注射（flow injection, FI）空气混合吸附预富集编结反应器（knotted reactor, KR）二次气体分隔洗脱法与火焰原子吸收光谱法（flame atomic absorption spectrum, FAAS）联用测定海洋生物样中的痕量铅。在预富集步骤,空气、络合剂和铅溶液在线混合,空气的引入,大大提高了铅的螯合物在KR内壁的吸附效果。在洗脱前,通入一段空气流,在洗脱过程中,即在非完全洗脱时,加入一段空气流,两段空气流的引入,大大降低了被分析物在洗脱液中的分散,提高了信号响应值,从而提高了浓集系数（enhancement factor, EF）。将空气混合吸附预富集与二次气体分隔洗脱法联用,使得KR吸附富集效果和洗脱效果达到了更高的水平。和微柱的低寿命、高反压相比,KR反压小,耐酸耐碱,寿命几乎无限长,对蠕动泵的要求很低,不易造成溶液渗漏等问题。在洗脱过程进行到第5秒时输入1 s空气流作为间隔,而不是等整个洗脱过程完成以后再输入空气流,此方法的优点是：洗脱完全,而且大大降低了被分析物在洗脱过程中的分散,吸收信号值大大增加。如果单纯地把洗脱时间降到5 s,那么洗脱会非常不完全,也就是没有洗脱干净,在管路中还会残存大量的被分析物,残存的被分析物被带入下一个样品分析中,会对整个实验造成很大的误差,所有的实验数据都将不准,失去数据利用价值。所以完全的洗脱是非常必要的,必须保证一定的洗脱时间。由于随着洗脱过程的进行,洗脱下来的被分析物呈逐渐减小的趋势,在以往洗脱方法中,等到整个洗脱过程全部进行完以后,被分析物在洗脱液中的分散已经相当严重了,导致所得到吸收信号值大大减小。在洗脱过程中插入空气流,即在非完全洗脱时插入空气流,降低了被分析物在洗脱过程中的分散,同时保证了洗脱的完全,大大提高了吸收信号峰值。优化了络合剂种类、浓度和酸度,样品富集时间和流速,空气混合吸附时的空气流速和时间,洗脱前第一次通气时间,预洗脱时间,洗脱过程中第二次通气时间等实验参数。在最佳实验条件下,铅在0.005～0.6 mg·L-1浓度范围内呈现良好的线性关系,铅的检出限（3σ）为2.2 μg·L-1。将新方法与直接火焰原子吸收法、传统的FI-KR空气混合吸附预富集普通洗脱法进行了比较,结果显示本方法的浓集系数更高。将该方法应用于海洋生物样中痕量铅的测定,测得鳝鱼、对虾、虾姑、鲟鱼、舌鳎和贻贝标准中的铅含量为0.34~1.92 μg·g-1;加标量为1.0 μg·g-1时,加标回收率为93.5%~96.4%;相对标准偏差为0.52%~2.94%。用FI-KR-FAAS空气混合吸附预富集,二次气体分隔洗脱法测定海洋生物样中的痕量铅,具有富集效果好,准确度高,精密度好,浓集系数高等优点,分析结果令人满意。     

A new laser shadowgraphy method for measurements of dynamic contact angle and simultaneous flow visualization in a sessile drop

A new laser shadowgraphy method is presented to measure the dynamic contact angle of a sessile drop on a nontransparent metal substrate and simultaneously visualize flow motions inside the drop. A collimated laser beam is refracted into the drop, then reflected on the substrate surface and finally refracted out of the drop to form a shadowgraphic image on a screen. The instant diameters of the refracted-shadowgraphic image, cooperated with the corresponding instant contact-diameters of the drop measured from the magnified top view, are used to determine the instant contact angles of the sessile drop. At the same time, flow motions, if any, in the drop can be visualized from the refracted-shadowgraphic image. The new method is demonstrated to be a very simple, accurate, and unique optical technique for simultaneous measuring of the dynamic contact angle of a liquid drop spreading on a nontransparent metal substrate with flow visualization in the drop.