交流示波极谱滴定法测定吡哌酸

本文介绍用交流示波极谱滴定法测定吡哌酸的含量。在ＨＣｌ－ＮａＡｃ缓冲溶液中，加入过量的Ｎａ－ＴＰＢ与吡哌酸作用生成沉淀，过滤后用亚铊标准溶液定滤液中过量的ＴＰＢ，由交流示波极谱图上ＴＰＢ的切口消失指示终点。本法操作简便，终点直观，应用于原料药样品的测定，并与药典法相对照，结果基本吻合。     

交流示波极谱滴定法测定氧氟沙星

１引言氧氟沙星（Ｏｆｌｏｘａｃｉｎ，ＯＦＬＸ）为新一代喹喏酮类抗菌药，其含量测定，文献报道可用分光光度法、ＨＰＬＣ、毛细管电泳法、离子选择电极法等。本文详细研究了交流示波极谱滴定法测定ＯＲＬＸ的实验条件，并用以测定其注射液和片剂的含量。２实验部分２．１仪器与试剂交流示波极谱仪，按文献（高鸿，示波极谱滴定，南京：江苏科技出版社，１９８５：１７）组装，ＵＶ－７５４分光光度计（上海第三分析仪器厂），ＯＦＬＸ注射液、片剂、化学对照品（北京制药厂）。容量仪器均经过校正，所用试剂四苯硼钠、硫酸亚铊及ＨＡｃ－…     

交流示波极谱滴定法测定氧氟沙星的研究

报道了用交流示波极谱滴定法测定氧氟沙星（ＯＦＸ）含量。用ｐＨ４．０的ＨＡｃ－ＮａＡｃ缓冲溶液溶解样品，加入过量的四苯硼钠（Ｎａ－ＴＰＢ）使药样沉淀完全１，过滤后滤液用硫酸亚铊标准溶液进行返滴定，由示波极谱图［ｄＥ／ｄｔ＝ｆ（Ｅ）］上ＴＰＢ切口的消失指示滴定终点。应用于片剂和注射剂测定，平均加标回收率为１００．０２％，相对标准偏差≤０．１７％。     

交流示波极谱滴定法测定度米芬含量

度米芬(Domiphen Bromide)是一种阳离子表面活性杀菌剂,其结构式为:测定方法有碘酸钾法、铁氰化钾法、四苯硼钠双相滴定法等。前两种方法操作繁琐,双相滴定法近终点时必须剧烈振摇,终点不易观察,且甩较大量氯仿既不经济又对人体有害。交流示波极谱四苯硼钠沉淀滴定法,可用于测定含氮有机药物。本文研究了交流示波极谱滴定法测定度米芬含量,方法准确,简单易行,终点灵敏直观。     

示波极谱滴定法测定生物碱氢溴酸盐类药物

以ＡｇＮＯ３作滴定剂，ＫＮＯ３和磺基水杨酸为极谱底液，采用交流示波极谱滴定法测定氢溴酸山莨菪碱、氢溴酸东莨菪碱、氢溴酸加兰他敏三种生物碱氢溴酸盐类药物的含量。该法到目前为止未见报道，具有快速、准确、终点直观的特点。     

Antilg de／dt—E曲线上的示波极谱滴定法

在示波极谱滴定中,当去极剂切口位于示波极谱图|dE/dt|的最大值附近时,利用Antilg dE/dt～E示波图来指示滴定终点能使终点变化更为敏锐。原来较难进行滴定的一些体系现在可用这种方法滴定。在50Hz的交流电频率下,用氨羧络合剂滴定了Cd~(2+)、Pb~(2+)、Zn~(2+)、Co~(2+),滴定结果符合分析要求。非线性放大还可应用于以dE/dt～E示波图的扩张或收缩来指示滴定终点的示波极谱滴定法及以荧光电位线的伸长或收缩来指示滴定终点的示波电位滴定法,以提高终点变化的敏锐性。以亚硝酸钠滴定对氨基苯磺酸为例说明了这一方法的可行性。     

Determination of aniline in environmental water samples by alternating-current oscillopolarographic titration

A new method for the determination of aniline in environmental water based on oscillopolarographic titration was presented in this paper. Several factors including the kind, concentration, and volume of acid, the dosage of potassium bromide, the temperature and concentration of concomitant substances were investigated in detail. The experimental results indicated that this method was simple, rapid, and sensitive. The linear range was 8.367×10-4 to 2.789×10-2 mol L-1, the relative standard deviation (R.S.D.) was lower than 0.96%, and the spiked recoveries of aniline in environmental water samples were in the range of 99.4-106.9% under the optimal conditions. The results indicated that the present method could be used as an alternative method for aniline determination in realworld water samples.     

磷酸苯丙哌林与曙红B的相互作用及其分析应用

在pH为3.35的HAc-NaAc酸性介质中,曙红B(EB)与磷酸苯丙哌林(BPP)借助静电作用和疏水作用力发生相互作用形成EB-BPP离子缔合物,导致体系共振光散射(RLS)强度显著增强,并在364 nm处出现最大散射峰。研究了体系的共振光散射光谱,吸收光谱及荧光光谱的特征,考察了实验条件及共存物质的影响。结果表明,在最佳的实验条件下,体系共振散射增强的强度与BPP的浓度在一定范围内呈良好的线性关系,其线性范围为0.04μg.mL-1~2.00μg.mL-1,检出限为14.31 ng.mL-1。据此,建立了一种高灵敏的定量测定活性组分BPP的方法。方法成功地用于药物、血清及尿样中BPP含量的测定。     

电化学发光法测定人尿中的磷酸苯丙哌林

基于磷酸苯丙哌林对联吡啶钌(Ru(bpy)32 )的电化学发光信号有较强的增敏作用,建立了一种检测磷酸苯丙哌林的电化学发光方法,并且应用于人尿中磷酸苯丙哌林的测定。结果表明,在0.02 mol/L Na2CO3-NaHCO3介质中,以方波为电解方式,联吡啶钌的质量浓度为1.0×10-5g/mL时,磷酸苯丙哌林对联吡啶钌电化学发光信号的增敏效果最好。在此条件下,测定磷酸苯丙哌林的线性范围为10~600 ng/mL,检出限为7.2 ng/mL,相对标准偏差RSD为1.6%(n=11,ρ=300 ng/mL)。     

Determination of glyphosate in water samples by alternating-current oscillopolarographic titration.

This paper describes a novel, simple and sensitive method for the determination of glyphosate in water samples by alternating-current oscillopolarographic titration. Under an acidic condition, glyphosate can be transferred into a nitrosocompound by reacting with NaNO2. The titration end-point was obtained by the formation of a sharp cut in the oscillopolarographic with infinitesimal NaNO2 on double platinum electrodes. The results showed that glyphosate had an excellent linear relationship over the range of 7.16 x 10(-6) - 4.14 x 10(-3) mol L(-1), the RSD of the proposed method was lower than 3%, and the spiked recoveries of three real water samples were in the range of 97.7 - 100.2%.     

Single-enzyme-based amperometric assay for phosphate ion

An amperometric assay for phosphate ion, using a single enzymatic process, has been developed. The enzyme used was pyruvate oxidase, which catalyzes the oxidation of pyruvate in the presence of oxygen and phosphate ion. The products of the enzymatic reaction are acetyl phosphate, carbon dioxide, and hydrogen peroxide. The latter was monitored by means of a hydrogen peroxide electrode and an oxidase meter. Phosphate ion in the concentration range of 50–500 μM can be measured within 4 min. Anions, such as pyrophosphate, sulfate, nitrate, nitrite, and acetate, gave only marginal responses.     

Gran电位滴定法测定乳酸环丙沙星

介绍了乳酸环丙沙星测定的Gran电位滴定法。采用Gran线性函数进行电位滴定,经图解外推或线性回归处理求出计量点,可直接用于测定乳酸环丙沙星原料药的含量。该法用于多批原料药的测定,结果与药典法基本一致。     

Novel approaches to analysis by flow injection gradient titration

Two novel procedures for flow injection gradient titration with the use of a single stock standard solution are proposed. In the multi-point single-line (MP-SL) method the calibration graph is constructed on the basis of a set of standard solutions, which are generated in a standard reservoir and subsequently injected into the titrant. According to the single-point multi-line (SP-ML) procedure the standard solution and a sample are injected into the titrant stream from four loops of different capacities, hence four calibration graphs are able to be constructed and the analytical result is calculated on the basis of a generalized slope of these graphs. Both approaches have been tested on the example of spectrophotometric acid–base titration of hydrochloric and acetic acids with using bromothymol blue and phenolphthalein as indicators, respectively, and sodium hydroxide as a titrant. Under optimized experimental conditions the analytical results of precision less than 1.8 and 2.5% (RSD) and of accuracy less than 3.0 and 5.4% (relative error (RE)) were obtained for MP-SL and SP-ML procedures, respectively, in ranges of 0.0031–0.0631 mol L⁻¹ for samples of hydrochloric acid and of 0.1680–1.7600 mol L⁻¹ for samples of acetic acid. The feasibility of both methods was illustrated by applying them to the total acidity determination in vinegar samples with precision lower than 0.5 and 2.9% (RSD) for MP-SL and SP-ML procedures, respectively.     

矿石中铅锌快速络合滴定法

利用铅锌矿中铅生成复盐沉淀 ,用EDTA标准溶液滴定锌 ,然后溶解复盐沉淀 ,加入过量EDTA标准溶液 ,用硝酸铅标准溶液反滴定。利用本方法测定铅锌矿中铅、锌 ,其铅的检测范围为质量分数 0 .4%～ 2 5 % ,锌的检测范围为质量分数 >1 % ,能满足地质检验中的分析误差要求。     

Polyelectrolyte titration using fluorescent indicator. I. Direct titration of anionic and cationic polyelectrolytes with 10−4N standard solutions

The polyelectrolyte titration, which was originally called colloid titration, is based on the stoichiometric reaction between positively charged colloidal particles and negatively charged ones. In the conventional method, the metachromatic color change of the indicator, toluidine blue, from blue to red-purple has been applied for the determination of the end point in the titration. 2.5 × 10^?3N potassium polyvinylsulfonate (KPVS) is usually used as the standard titrant. In this work, fluorescent indicators such as 6-(p-toluidino)-2-naphthalene sulfonate (TNS), acridine orange, etc., have been introduced. The fluorescence intensity was measured using the spectrophotometer equipped with magnetic stirrer and connected with a vinyl tube attached to the hand piston burette. For example, TNS is practically nonfluorescent, but it exhibits strong fluorescence when it is bound to a cationic polyelectrolyte (CP). The fluorescence of the TNS–CP complex is diminished by titration with KPVS standard solution since TNS is liberated from the complex by substitution with KPVS. After the equivalent point, the fluorescence intensity becomes constant and the end point can thus be detected by that point. It has been elucidated that the very dilute standard solution like 1 × 10^?4N can be used because the sensitivity of fluorescence detection is extremely high. © 1993 John Wiley & Sons, Inc.