Flow-injection Spectrophotometric Determination of Uric Acid in Urine via Prussian Blue Reaction

A simple and sensitive flow injection(FI) spectrophotometric method was reported for the determination of uric acid based on the reduction of Fe(III)/ferricyanide in the presence of uric acid. The in situ reduced ions reacted with unreduced portion of ferricyanide/Fe(III) to form soluble Prussian blue, which was monitored at an absorption wavelength of 735 nm. The optimized conditions allow a linear calibration graph in a concentration range of 1―100 μmol/L. The relative standard deviation was in a range of 0.5%―2.5%, with a detection limit(3σ blank) of 0.3 μmol/L and a sampling frequency of 60 injection/h was obtained. The effect of common substances present in human physiological fluids on the determination of uric acid was examined. The method was applied to determining uric acid in human urine samples with the recoveries in a range of 96%―105%. The results agree well with those by spectrophotometric reference method at a confidence level of 95%. Spectrophotometric procedures for uric acid determination in clinical samples were reviewed briefly.     

Spectrophotometric Determination of Selected Antibiotics Using Prussian Blue Reaction

A simple, sensitive and accurate spectrophotometric method has been described for the determination of ampicillin(I), amoxicillin trihydrate(II) and cefazolin sodium(III). The procedure is based on the formation of Prussian Blue (PB) complex. The reaction between the acidic hydrolysis products of antibiotics (T = 60 °C) with mixture of Fe³⁺ and hexacyanoferrate(III) ions was evaluated for the spectrophotometric determination of the mentioned drugs. The maximum absorbance of the colored complex occurs at λ = 700 nm and the molar absorptivity is 3.0 × 10⁴ 1 mol^?1cm^?1. The effect of various parameters such as concentration of K₃Fe(CN)₆ and Fe³⁺, nature and amount of acids used, temperature and time of heating were investigated. Under optimum conditions the linear range of calibration graph was 2.0–12.0, 5.0–13.5 and 3.0–12.0 μg mL^?1 for ampicillin, amoxicillin and cefazolin, respectively. The relative standard deviation for the determination of 10 μg mL^?1 of antibiotics was about 0.5–1.5%. The proposed method was successfully applied to the determination of selected antibiotics from pharmaceutical preparations. The validity of the method was tested by the official methods and by the recovery studies of standard addition to pharmaceuticals.     

吗啡的流动注射分光光度法分析研究

本文建立了吗啡的流动注射分光光度分析法。在优化条件下,线性检测范围为30～700μg/ml,回归方程为h=0.0250+1.74×10~(-3)C,相关系数为0.9999,并用于吗啡样品的分析。回收率为99.9％,相对标准偏差为0.43％,样品分析速度为240次/小时。     

Automated Determination of Captopril by Flow and Sequential Injection Analysis: A Review

The present study intends to present a review of automated methods for the determination of Captopril—an angiotensin converting enzyme (ACE) inhibitor—using flow or sequential injection analysis. The review covers a range of more than fifteen years of published research on this topic (1993–today). The methods are classified according to the detection systems in three categories, namely spectrophotometric, chemiluminescence, and electroanalytical. The principles and main analytical figures of merit of the reported studies are presented and discussed.     

流动注射—分光光度法测定植物中钼

本文将流动注射分析(FIA)引入Mo-SCN~--RhB三元缔合体系测定痕量Mo。不需萃取,反应迅速,重现性好。0～1.6μg/ml Mo符合比耳定律,检测限0.02μg/ml。用预混线圈R_1可克服Fe~(3+)等元素与SCN~-络合的干扰。测定了植物中Mo,结果满意。     

流动注射分光光度法测定微量镉的研究

研究了在Ｔｒｉｔｏｎ Ｘ－１００存在下,以二溴羧基苯基氮氨基偶氮苯（ＤＢＫＤＡＡ）为显色剂的流动注射分光光度测定微量镉的新方法。用ｐＨ１０．５的硼砂－氢氧化钠缓冲溶液作栽流,ＤＢＫＤＡＡ和Ｔｒｉｔｏｎ Ｘ－１００的混合液作试剂流,采用双道流路,在５２０ｎｍ波长下检测反应生成的红色配合物。方法的线性范围是０～０．８０μｇ／ｍＬ,进样频率为１８０样次／小时,直接应用于工业废水中微量镉的测定,结果满意。     

Spectrophotometric Determination of Uranium(VI) with Chlorophosphonazo-mN by Flow Injection Analysis

Abstract

A sensitive and selective spectrophotometric flow injection analysis (FIA) method with chlorophosphonazo-mN has been developed for the determination of uranium(VI) in standard ore samples. Most of interfering ions are effectively eliminated by the masking reagent of diethylenetriaminepentaacetic acid (DTPA). In the U(VI)-chlorophosphonazo-mN system, the maximum absorption wavelength is at 680 nm and Beer's law is obeyed in the range of 1 to 15 μg ml^?1. The correlation coefficient of the calibration curve is 0.9998, the sampling frenquency is 60 h^?1, and the detection limit for uranium(VI) is 0.5 μg ml^?1. The composition of the U(VI)-chlorophosphonazo-nN complex was established to be 1:2 by flow-through spectrophotometric and conventional molar ratios methods.     

Determination of Orciprenaline Using a Flow Injection Analysis System with Sequential Potentiometric and Spectrophotometric Detection

Abstract

This work describes an attempt to have a flow injection analysis (FIA) system for Orciprenaline with potentiometric and spectrophotometric detectors working sequentially. The potentiometric detection was performed using an orciprenaline ion-selective electrode made of orciprenaline ion-associate with phosphotungstic acid incorporated in a PVC matrix membrane, followed by sequential spectrophotometric detection of the same sample using the reaction of orciprenaline with phosphomolybdic acid in alkaline medium and measurement at 670 nm using a USB2000 fiber-optic spectrophotometer. The method was applied and validated for the assay of different samples that are 1.0 × 10^?2–1.0 × 10^?7 M orciprenaline, and the recovery values for Alupent® tablets, plasma and urine sample ranged from 99.39–100.93, 99.87–100.57, and 98.83–100.64 respectively for the potentiometric detector and 99.66–100.58, 99.78–100.69 and 99.12–100.92 respectively for the sequential spectrophotometric detector. It was found that using the double detection system compensated for both the unselectivity of the spectrophotometric method and the low detection limit of the potentiometric method (6.3 × 10^?4 M). Although two detectors were used in the measurements, the method is still very simple to design and apply, in addition to being rapid and less expensive than other more sophisticated techniques applied in the literature and can therefore be used for other pharmaceutical compounds as well.     

水杨基荧光酮胶束增敏流动注射分光光度法测定微量锗

本文将锗一水杨基荧光酮一溴化十六烷基三甲基铵胶束五色体系应用于流动注射分析，建立了测定微量锗的快速方法。方法采用单通道流路及合并带流路进行试验。对有关的管路参数及试剂浓度等影响因素进行了探讨。优化的流动注射分析体系对锗的检测灵敏度高、重现性好。方法用于混合成试样及有机锗生物制品中锗的测定，结果满意。     

流动注射分光光度法测定微量铜的研究

研究了在ＴｒｉｔｏｎＮ－１０１存在下，２－羟基－３－羧基－５－磺酸基苯重氮氨基偶氮苯（ＨＣＳ－ＤＡＡ）显色流动注射光度测定微量铜的新方法，用ｐＨ０．４～１１．５Ｎａ２Ｂ４Ｏ７－ＮａＯＨ缓冲溶液作载流，ＨＣＳＤＡＡ和ＴｒｉｔｏｎＮ－１０１的混合试剂作试剂流，采双道流路，５３０ｎｍ检测反应生成红色配合物，方法线性范围是０．０２４～０．２０μｇ／ｍＬ，检出限为８ｎｇ／ｍＬ，进样频率为１００样次／ｈ，直接     

流动注射分光光度法测定砷的研究

本文采用自行设计制造的氢化物发生及吸收装置,将流动注射技术同氢化物发生分光光度法结合在一起,设计了一种不使用载气的流动注射分析系统并对该系统的测定条件进行了实验研究,实验用HNO_3-AgNO_3-聚乙烯醇-乙醇混合液作吸收液,结果证明该系统具有操作简便,成本低廉,分析速度快(30次/小时),灵敏度高,重现性好及线性范围可调的优点。     

甲氧氯普胺的流动注射光度分析

基于在盐酸介质中,利用甲氧氯普胺－亚硝酸钠－α－萘胺的重氮化－偶合反应,建立了流动注射光度法测定甲氯普胺的新方法,利用单纯形优化法选择了最佳实验条件。方法的线性范围为0.0-30mg/L,进样频率为160／h。11次重复测定的相对标准偏差小于0.6％,该方法已成功用于药物中甲氧氯普胺含量的测定,测定结果与药典法对照,并经统计学处理,结果满意。     

Flow Injection Catalytic Determination of Vanadium using the Indicator Reaction between Victoria Blue B and Bromate and A Citric Acid Activator

ABSTRACT

A flow injection catalytic method is proposed for determination of trace vanadium based on its catalytic action on a new indicator reaction between Victoria blue B (VBB) and potassium bromate in the presence of citric acid as an activator and in dilute sulfuric acid medium. The reaction is monitored spectrophotometrically by measuring the decrease in absorbance of VBB injected at the maximum absorption wavelength of 618 nm. The detection limit is 0.5 ng ml^?1 and is independent of the initial valence state of vanadium. The relative standard deviation is 1.5% obtained from 11 standard solutions each containing 40 ng ml^?1 of vanadium. The sampling rate is about 15 samples per hour. This method is very simple and has been applied to the determination of trace vanadium in some natural waters with recoveries of 93-103%.     

饮料、甜橙、药片和尿液中维生素C的流动注射分析——2,6-二氯吲哚酚光度法

流动注射2,6-二氯吲哚酚光度法测定维生素C具有灵敏,快速的特点,检出限为0.5μg/ml,分析速度120样/h,取Vc 40μg/ml时测量的相对标准偏差为±0.5％。测定各类样品中Vc含量获得较好的结果。     

微孔膜气体扩散分离流动注射光度法测定废水中氰化物

研究了利用吡啶-巴比妥酸显色体系反应的中间产物,采用微孔膜气体扩散分离流动注射分析技术测定工业废水中氰化物,该法具有简便、快速并能消除某些干扰的特点。进样频率为65个样/h,检出限为0.02μg/ml,取氰化物2.5μg/ml时测量的相对标准偏差为0.3％(n=20),测定实际样品结果令人满意。     

流动注射催化分光光度法测定钌的研究

利用钌（Ⅲ）对过氧化氢氧化还原型百里酚酞显色反应的显著催化作用，建立了钌的新流动注射催化分光光度分析法，该法快速灵敏、简便，用于实际样品分析，结果良好。     

Catalytic Spectrophotometric Determination of Vanadium by Flow Injection Analysis

Determination of trace amount of vanadium in water was studied by flow injection analysis. Catalytic spectrophotometric detection was performed with bromate oxidation of o-phenylenediamine and by addition of tiron as an activator and also as a masking agent. Vanadium can be determined with sample rate of ca. 60–70 samples/hour with in a range of 0.01 ppm to 0.5 ppm V and with r.s.d. 0.555% for 0.1 ppm V and 0.37% for 0.3 ppm V. Interference by Fe(III) can be reduced by using 0.3% NH₄F as a carrier solution.     

百里酚蓝分光光度法测定阿昔洛韦及其反应机理

在pH 7.84的NaH2PO4-Na2HPO4缓冲介质中,百里酚蓝与阿昔洛韦反应形成离子缔合物,最大吸收波长为596 nm,并在436 nm波长处产生负吸收。阿昔洛韦的浓度在2.05×10-6~2.38×10-5mol.L-1内遵守比耳定律,ε=3.19×104L.mol-1.cm-1,检出限为6.21×10-7mol.L-1。若用双波长叠加,ε=4.46×104L.mol-1.cm-1,检出限为5.13×10-7mol.L-1。用于药品、血浆及尿液中阿昔洛韦的测定,RSD为0.68%~2.76%,回收率为99.1%~103.3%。对反应机理进行探讨,表明离子缔合物的形成不仅由静电引力引起,且与荷移作用和范德华力有关。     

流动注射掺杂普鲁士蓝碳糊电极测定过氧化氢

在化学法制得普鲁士蓝(PB)粉末的基础上,用固体石蜡作粘合剂,将PB粉末和石墨粉按一定比例充分混合,制得掺杂PB的碳糊电极(PBCPE)。研究了该修饰电极的制备,电化学性质及对H2O2的电催化作用。该修饰电极在0.5mol/L的KCl底液中进行循环伏安实验,于0.2V(vs.SCE)附近出现一对氧化还原峰,扫速为30mV/s时,峰电位差67mV,重现性良好。采用流动注射进样,基于PBCPE电极成功实现了恒电位快速检测医用消毒水中H2O2的浓度。最佳检测电位为-0.3V,进样频率为120次/小时。响应电流与H2O2的浓度在0.08～3.2mmol/L范围内呈良好的线性关系,线性相关系数为0.9994,检出限为2.4×10-6mol/L(S/N=3)。     

耐尔蓝分光光度法间接测定铵

以耐尔蓝为显色剂，采用分光光度法进行铵的测定。选择了ＮａＯＨ碱解蒸馏分离氨的条件，探讨了表面活性剂ＯＰ，ＳＤＳ增敏增溶作用，分别测定了雨水，土壤，绿叶中铵含量，结果满意。