钒酸铵氧化-分光光度法测定盐酸氯丙嗪

在磷酸介质中,钒酸铵与盐酸氯丙嗪反应生成红色氧化产物,其最大吸收波长为524nm;据此建立了测定盐酸氯丙嗪含量的钒酸铵氧化-分光光度法,并将其用于直接测定药物制剂中的盐酸氯丙嗪.结果表明,当盐酸氯丙嗪的浓度处于10.0～100mg/L和100～360mg/L范围内时,被测定体系的吸光度与盐酸氯丙嗪的浓度之间呈良好的线性关系;线性回归方程分别为A=-0.061 69+0.010 05c(mg/L,r=0.998 8)、A=0.494+0.004 43c(mg/L,r=0.998 8),检出限为1.96mg/L,相对标准偏差为0.29%,回收率为94.9%～102.9%.     

1,2-萘醌-4-磺酸钠体系分光光度法测定磺胺甲噁唑

采用1,2-萘醌-4-磺酸钠体系分光光度法测定磺胺甲噁唑(SMZ)。磺胺甲噁唑与1,2-萘醌-4-磺酸钠在pH=10.0的缓冲溶液中发生亲核取代反应生成橙红色的产物,组成比为1:1,最大吸收波长λ=476 nm;表观摩尔吸光系数ε=6.44×103L/(mol.cm);SMZ浓度在0.2~60 mg/L范围内呈良好的线性关系;线性回归方程为A=0.02452 0.02301C(mg/L),线性相关系数r=0.9991;检出限为0.08 mg/L;RSD为0.25%(20 mg/L,n=11);平均回收率为98.7%以上。优化了对磺胺甲噁唑的测定条件。初步探讨了反应机理,应用拟定的方法测定磺胺甲噁唑的含量,与药典法相比,结果满意。     

羟氨苄青霉素干糖浆中有效成分的测定

羟氨苄青霉素为抗生素类药物,主要用于敏感菌所致的呼吸道,尿路和皮肤软组织等感染的治疗.鉴于羟氨苄青霉素分子中含有脂肪族伯氨基.而脂肪族伯氨基在一定条件下可以与茚三酮发生显色反应,本文详细研究了羟氨苄青霉素与茚三酮的显色反应条件,建立了简便的分光光度法.测定波长是565nm;线性范围是5-55mg/L;表观摩尔吸光系数是7.28×10~3L·mol~(-1)·cm~(-1).对医药干糖浆进行测定,结果与药典方法(硫醇汞盐紫外分光光度法)一致,回收率符合要求.     

微顺序注射-分光光度法快速测定海水中总磷

基于微顺序注射-阀上实验室,采用磷钼蓝分光光度法测定了海水中总磷,对实验参数进行了优化,并选取了海水中主要成分离子进行了干扰实验。结果表明,海水中总磷质量浓度在0.009~1mg/L范围内与吸光度呈线性关系(r=0.9995),方法的检出限为0.003mg/L。该法测定秦皇岛黄金海岸表层海水中总磷浓度为0.090mg/L,与国标法测定结果0.088mg/L无显著性差异;测定含磷浓度为0.20mg/L的人工海水,相对标准偏差(RSD)为2.4%,样品加标回收率为94.4%~95.7%;海水中主要离子对本实验方法测定产生的干扰在5%以内。     

茚三酮分光光度法测定水中氨氮

根据茚三酮在一定条件下可与氨发生显色反应的原理,提出了利用茚三酮测定氨氮含量的新方法,探讨了显色剂和还原剂用量、介质环境、反应温度及反应时间等条件对反应体系的影响。在优化条件下测定了氨氮的工作曲线,在实际样品测量中,与纳氏试剂分光光度法进行了比较。氨氮检测范围0.01~5 mg/L,优于纳氏试剂法,可广泛应用于检测机构的水质检测活动。     

FeCl3-铁氰化钾体系分光光度法测定酚磺乙胺

采用铁氰化钾-FeCl3体系分光光度法测定酚磺乙胺。研究表明,酚磺乙胺可使Fe(Ⅲ)还原为Fe(Ⅱ),还原生成的Fe(Ⅱ)可以与K3[Fe(CN)6]反应生成可溶性普鲁士蓝KFe[Fe(CN)6],其最大吸收波长位于710 nm处。酚磺乙胺的质量浓度在0.064～9.6 mg/L范围内与吸光度呈现良好线性关系,线性回归方程A=0.03242+0.08244ρ(mg/L),相关系数r=0.9994,摩尔吸光系数ε=2.17×104L/(mol·cm),检出限0.047 mg/L;相对标准偏差(3.20 mg/L,n=11)为2.4%。方法用于测定药物注射液中酚磺乙胺含量,回收率为98.3%～102.9%。     

基于氯冉酸荷移分光光度法测定乙酰螺旋霉素含量

研究了乙酰螺旋霉素和氯冉酸在甲醇介质中发生的荷移络合反应,确定了最佳条件,从而建立了一种简便快速测定乙酰螺旋霉素的荷移分光光度法。荷移络合物的最大吸收波长为λ=531 nm,络合比为1∶1,该络合物的吸光度与乙酰螺旋霉素的浓度在1.2～20 mg/L范围内呈线性关系,线性相关系数r=0.9998,检出限为0.5 mg/L,相对标准偏差为1.2%,回收率为99.5%～101.2%。本方法用于对乙酰螺旋霉素片含量的测定,结果较为满意。     

萃取分光光度法测定盐酸洛美沙星

提出了测定盐酸洛美沙星 (LMX)的萃取分光光度法 ,该法基于在弱酸性条件下 ,盐酸洛美沙星与溴甲酚绿 (BMG)反应生成可被三氯甲烷萃取的离子对缔合物 ,其最大吸收波长为 415nm。药物浓度在 1～ 15mg/L(r=0 .9997)范围内符合比耳定律。表观摩尔吸收系数ε =2 .5× 10 4 L·mol-1·cm-1。最低检出限为 0 .0 14mg/L。回收率为 98.9%～ 10 1.6 %。该法可成功的用于药物制剂中洛美沙星含量的测定     

荷移反应分光光度法测定苯巴比妥钠

采用分光光度法研究了电子给体苯巴比妥钠与π电子受体茜素红的荷移反应,建立了荷移分光光度法测定苯巴比妥钠的方法。在水溶液中,苯巴比妥钠与茜素红荷移络合物的最大吸收波长为530 nm,该络合物的组成为1∶1,表观摩尔吸光系数ε为4.43×103L.mol-1.cm-1,稳定常数为2.30×105。药物质量浓度在5~40 mg/L范围内符合比尔定律,相关系数为0.9996。当苯巴比妥钠浓度为20 mg/L时,10次测定结果的相对标准偏差为1.3%。测定了针剂中的苯巴比妥钠,加标回收率在98.9%~105%之间。     

可见分光光度法测定卡那霉素的含量

基于硫酸卡那霉素与茚三酮作用形成的络合物在563nm处有特征吸收,以茚三酮为显色剂,采用可见分光光度法测定硫酸卡那霉素的含量。通过考察缓冲溶液的酸度及其用量、茚三酮溶液的用量、加热反应时间和加样顺序等条件得到最佳显色反应条件。硫酸卡那霉素的质量浓度在0.074~0.465g·L~(-1)范围内与吸光度呈线性关系,检出限(0.01/k)为0.026g·L~(-1)。加标回收率在95.5%~98.4%之间,测定值的相对标准偏差(n=12)小于3.0%。     

Simultaneous determination of carvedilol and ampicillin sodium by synchronous fluorimetry

The carvedilol and ampicillin sodium were simultaneously determined by the synchronous fluorimetry. With excitation wavelength at 254 nm, the maximum emission wavelengths of carvedilol and ampicillin sodium were at 357 and 426 nm, respectively. Because the emission spectra of carvedilol and ampicillin sodium were overlapped partially, carvedilol and ampicillin sodium cannot be determined directly by normal fluorimetric method. However, the synchronous fluorimetry can be used for determining both drugs simultaneously without separation procedure. The (Delta)(lambda) = 80 nm was used. Iso-propanol was selected as sensing reagent. Effects of pH, organic solvents and foreign ions on the determination of both drugs were studied. The linear relationship was obtained between the relative fluorescence intensity and concentration of carvedilol and ampicillin sodium in the range of 0.005-0.1 and 5.0-70.0 microg ml(-1), respectively. The linear regression equation of calibration graph for carvedilol is C = 0.000151F - 0.00210, and for ampicillin sodium is C = 0.0770F - 2.62. The correlation coefficient of linear regression equation is 0.9995 for carvedilol and 0.9998 for ampicillin sodium, respectively. The detection limit is 1 ng ml(-1) for carvedilol and 1 microg ml(-1) for ampicillin sodium. The relative standard deviations of carvidelol and ampicillin sodium are 2.47 and 1.61%, respectively. The recovery is from 96.0 to 103.0% for carcvedilol and from 98.0 to 105.0% for ampicillin sodium. This method was rapid, simple and highly sensitive for the determination of carvedilol and ampicillin sodium without pre-separation. The results obtained by this method agreed with those by the official methods. This method can be used for the determination of carvedilol and ampicillin sodium in the medicine dosage.     

Spectrophotometric determination of ampicillin sodium in pharmaceutical products using sodium 1,2-naphthoquinone-4-sulfonic as the chromogentic reagent

Spectrophotometric determination of ampicillin sodium is described. The ampicillin sodium reacts with sodium 1,2-naphthoquinone-4-sulfonic in pH 9.00 buffer solution to form a salmon pink compound, and its maximum absorption wavelength is at 463 nm, epsilon463 = 1.14 x 10(4). The absorbance of ampicillin sodium from 2.0-80 microg ml(-1) obeys Beer's law. The linear regression equation of the calibration graph is C = 40.24A - 2.603, with a linear regression correlation coefficient is 0.9997, the detection limit is 1.5 microg ml(-1), recovery is from 97.23 to 104.5%. Effects of pH, surfactant, organic solvents, and foreign ions on the determination of ampicillin sodium have been examined. This method is rapid and simple, and can be used for the determination of ampicillin sodium in the injection solution of ampicillin sodium. The results obtained by this method agreed with those by the official method (HPLC).     

Indirect determination of ampicillin sodium with sodium nitrate-ammonium thiocyanate-water system by extraction-flotation of cuprous thiocyanate

A novel method for indirect determination of ampicillin sodium by the extraction-flotation is proposed in this paper. It is indicated that the degradation of ampicillin sodium took place in the presence of 0.30 M sodium hydroxide in boiling water for 20 min. At pH 4.0, in the presence of ammonium thiocyanate, the thiol group of the degradation product of ampicillin sodium could reduce copper(II) to copper(I) due to the formation of the emulsion cuprous thiocyanate precipitation. By determining the residual amount of copper(II) in the solution and calculating the flotation yield of cuprous thiocyanate, the indirect determination of ampicillin sodium can be performed. When the concentration of cooper(II) was 5.0 μg/mL, a good linear relationship was obtained between the flotation yield of cuprous thiocyanate and the amount of ampicillin sodium in the range of 0.40～9.6 μg/mL. The linear equation is E = 4.1469 + 3.7949c with the correlation coefficient r = 0.9992, and the detection limit (3σ/K) of 0.37 μg/mL. Each parameter has been optimized and the reaction mechanism has been studied. The method has been successfully applied to the determination of ampicillin sodium in pharmaceutical, human plasma and urine samples. Analytical results obtained are satisfactory.     

Flow-injection chemiluminescence determination of penicillin antibiotics in drugs and human urine using luminol-Ag(III) complex system

A chemiluminescent (CL) system based on the reaction of an Ag(III) complex with luminol in alkaline medium is presented. Gamma order of magnitude penicillin species antibiotics could dramatically enhance CL intensities. Coupled with flow injection analysis (FIA), a novel sensitive chemiluminescent analytical technique for some penicillin antibiotics in drugs and urine samples is introduced. Under optimum conditions, benzylpenicillin sodium, amoxicillin, ampicillin and cloxacillin sodium were determinated. Detection limits of this method are 70 ng/mL for benzylpenicillin sodium, 67 ng/mL for amoxicillin, 169 ng/mL for ampicillin and 64 ng/mL for cloxacillin sodium. For the spiked urine samples, the recoveries of the four drugs were in the range of 106–112% for benzylpenicillin sodium, 104–110% for amoxicillin, 104–106% for ampicillin, and 103–105% for cloxacillin sodium. Based on the fluorescence spectra, free radical trapping experiment, and chemiluminescent spectra, a possible reaction mechanism is suggested.     

固相萃取-胶束电动色谱法测定牛奶中的4种β-内酰胺类抗生素

建立了同时分离检测牛奶中的氨苄西林、阿莫西林、青霉素V和头孢氨苄4种β-内酰胺类抗生素的固相萃取-胶束电动色谱法。牛奶样品经沉淀蛋白后,采用HLB固相萃取柱净化浓缩;以含十二烷基硫酸钠(SDS)的磷酸盐为缓冲液,胶束电动色谱分离,210 nm波长下检测。分离电压为18 kV,于9 min内达到基线分离。各组分在0.5～20 mg/L范围内呈良好的线性关系,相关系数(r2)为0.9943～0.9976;检出限为0.16～0.20 mg/L;除了阿莫西林外,回收率均大于70%。该方法准确可靠,重复性好,灵敏度高,可以用于牛奶中β-内酰胺类抗生素的定量检测。     

Flow injection chemiluminescence analysis of some penicillins by their sensitizing effect on the potassium permanganate-glyoxal reaction.

A new chemiluminescence method using flow injection is described for the determination of four penicillins, namely: phenoxymethylpenicillin potassium, amoxicillin, ampicillin, and ampicillin sodium. The method is based on sensitizing effect of these drugs on the chemiluminescence reaction of potassium permanganate in sulfuric acid with glyoxal. The different experimental parameters affecting the chemiluminescence intensity were carefully studied and incorporated into the procedure. The method allows the determination of 0.1-1.0 microg/ml phenoxymethylpenicillin potassium, 0.1-1.0 microg/ml amoxicillin, 0.1-1.0 microg/ml ampicillin, and 0.1-1.0 microg/ml ampicillin sodium. The method was successfully applied to the determination of four penicillin antibiotics in pharmaceutical preparations.     

Rapid High Performance Liquid Chromatographic Determination of Ampicillin in Human Urine

Abstract

A rapid, sensitive and specific HPLC assay for the determination of ampicillin in human urine is developed.

Ampicillin was directly measured in human urine at 225 nm using a reversed phase column (Synchropack RP-P) and a mobile phase composed of (1:9 methanol-sodium acetate solution, 0.01 M, pH 4). The analysis required no longer than 10 min. Linear correlation between the peak height ratio of ampicillin to cefoxitin sodium (internal standard) and ampicillin concentration in urine over the range 10–100 μg ml^?1 was obtained. The developed method proved to be advantageous as it monitors ampicillin level in urine. Moreover, the urinary excretion of ampicillin in human subjects after an oral administration of 500 mg ampicillin capsules was established using the proposed method.     

A novel method for the preconcentration and determination of ampicillin using electromembrane microextraction followed by high‐performance liquid chromatography

Electromembrane extraction was used with high‐performance liquid chromatography for preconcentration and determination of ampicillin residues in cow milk. Ampicillin is transferred from an aqueous solution through a thin layer containing octan‐1‐ol, silver nanoparticles, and reduced graphene oxide which serves as a supported liquid membrane. Inside the fiber impregnated with supported liquid membrane mixture was filled 10 µL of an acceptor phase. Experimental parameters were optimized for extraction efficiency of ampicillin. Under the optimized conditions, the proposed method provided acceptable linear range (2–100 µg/L), satisfactory repeatability (RSD% < 7.1), low limit of detection (0.6 µg/L), and a high enrichment factor (295) corresponding to extraction recovery of 37%. Consequently, the proposed method was successfully applied for the determination of ampicillin residues in different cow milks.     

药物头孢Ⅳ号和氨苄青霉素及其生物合成前体的毛细管区带电泳分离

 研究了同分异构体药物头孢Ⅳ号和氨苄青霉素及其目标生物合成前体三肽Ｄ－苯丙氨酸－Ｌ－半胱氨酸－Ｄ－缬氨酸、Ｌ－苯丙氨酸－Ｌ－半胱氨酸－Ｄ－缬氨酸的毛细管区带电泳分离。结果表明，采用含１２ｍｍｏｌ／Ｌ二甲基β－环糊精（ＤＭ－β－ＣＤ）的５０ｍｍｏｌ／ＬＴｒｉｓ－Ｈ３ＰＯ４缓冲溶液（ｐＨ２．３）既可将头孢Ⅳ号和氨苄青霉素分离，又可将Ｄ－苯丙氨酸－Ｌ－半胱氨酸－Ｄ－缬氨酸、Ｌ－苯丙氨酸－Ｌ－半胱氨酸－Ｄ－缬氨酸分离。     

Experimental and theoretical study of the electrochemical synthesis of silver nanoparticles using ampicillin as a stabilizing reagent

Electrochemical synthesis of silver nanoparticles on the surface of glassy carbon electrode using ampicillin as a stabilizing reagent are prepared. The silver nanoparticles are characterized by scanning electron microscopy, cyclic voltammetry, and infrared spectrometry. The electrochemical catalysis of AgNPs for sodium sulfide was demonstrated. The relationship between the molecular structure of ampicillin and the dispersion of GNPs on the surface of GCE as well as the catalysis of GNPs for sodium sulfide was discussed.