Flow Injection Analysis of Famotidine with Spectrophotometric Detection

Abstract

A flow injection determination of famotidine has been described. The method is based on the reaction of the drug with cupric acetate to form a blue coloured complex which shows absorption maxima at 314 nm and 630 nm. For an injection volume of 100 μl calibration graphs were rectilinear from 10- 50 μg. ml^?1 and 50–500 μg.ml^?1 of drug at the two wavelengths respectively. Samples could be analysed at rates upto 60 per hour with a relative standard deviation less than 1.4%. The method was evaluated by analysis of the pure drug and commercial formulations. The results compare well with those obtained by official methods.     

Spectrophotometric Determination of Cefadroxil in Drug Formulations using flow Injection Analysis

ABSTRACT

A flow injection analysis method for the determination of cefadroxil is proposed. The method is based on the hydrolysis of cefadroxil in sodium hydroxide solution followed by treatment with 1,4-phenylenediamine and Fe(III) in sulphuric acid solution to produce a violet color which has a maximum absorption at 600 nm. Variables such as acidity, reagent concentrations, flow rate of reagents and other FI parameters were optimized to produce the most sensitive and reproducible results. The calibration graph is linear between 80 - 320 mg/l. The detection limit is 40 mg/l with a relative standard deviation, RSD (n=6) of 1.8%. The proposed method, combining the advantages of speed and accuracy was applied to the determination of cefadroxil in pharmaceutical preparations. The results have been compared with those obtained using HPLC method (USP-procedure). Excellent agreement between the results of the proposed method and the HPLC method was observed.     

Flow Injection Spectrophotometric Determination of 2,4‐D Herbicide

2,4‐Dichlorophenoxy acetic acid herbicide is spectrophotometrically determined by diazotization method in a flow injection assembly. The method is based on base hydrolysis of herbicides. The hydrolyzed product 2,4‐dichlorophenol is reacted with diazotized sulfanilic acid. The absorbance of the resulting coloured product was measured at 480 nm. The calibration graph is linear over the range of 0.2–20 μgmL^?1, with a relative standard deviation of (RSD) of 7.2% and sample throughput of 90 samples h^?1. The % recovery for determination of 2,4‐dichlorophenoxy acetic acid was found to be 92.0–95.3%. The method is easy, simple and faster than the established chromatographic method. The method was applied for determination of 2,4‐dichlorophenoxy acetic acid herbicide in commercial formulations and for residue determination in fruits and food samples.     

流动注射—恒电流电位溶出法测定氯离子的研究

本文制备了以银丝为工作电极的流通式电解池并将其接入流动注射体系中,在NaNO_3支持电解质溶液中,氯离子可用恒电流溶出法进行测定。加偶氮胂I饱和乙醇溶液于样液中峰高显著增高。其加入量愈多灵敏度愈高。用拉丁正交试验优化实验条件。在1×10~(-6)～8×10~(-3)mol/L Cl~-浓度范围,其溶出峰高与Cl~-浓度有线性关系。本法简单、快速、重现性好。已用于自来水、地下水和雨水的分析,获得满意结果,分析速度为80～120样/h。     

双光束流动注射光度法测定生活用水中氯离子

将流动注射分析技术应用到双光束分光光度法中，对其理论和实验技术进行了研究，采用自行组装的流动注射系统进行了生活用水中氯离子的测定，获得满意结果。     

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。     

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.     

Flow Injection Spectrofluorimetric Determination of Terbium (III) Based on Solubilizing its Ternary Complex in Micellar Solution

Abstract

A flow injection spectrofluorimetric method has been developed for the determination of terbium (III) based on solubilizing its ternary complex with pi valoyitrifluoroacetone (PTA) and trioctylphosphine oxide(TOPO) in micellar solution of nona (oxyethylene) dodecyl ether (BL-9EX). Accuracy and reproducibility are good up to 16 ng/ml of terbium (III) and 80 samples per hour can be analyzed. The relative standard deviation was less than 1.0 %. No interferences from 20-fold excesses of 11 rare earth ions were observed.     

Spectrophotometric Determination of Ampicillin with Some Nitro Compounds

Abstract

A spectrophotometric procedure for the determination of ampicillin (Amp.) in pure solutions and in its pharmaceutical preparations has been developed. This new method offers advantages of simplicity, rapidity and stability in comparison with the official BP (1980) method. The proposed method is based on the formation of a colour condensation product through the reaction of ampicillin and nitrobenzene derivatives in an alkaline aqueous-acetone medium 40% (v/v). Beer's law is obeyed in the range 0.5–28 μg ml^?1. The colours were produced within 20 min. after heating at 60±5°C and stable for at least 6 h. The method is relatively accurate (recovery 100±2%) and precise (RSD 1.9%) and can be used successfully for the preparation of capsules, syrup and ampoules.     

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。     

Novel Spectrophotometric Method for Determination of Macro-paracetamol via Reaction with Bromine

The reaction between Br2 and paracetamol(p-AAP) leads to the formation of a coloured product, which can be used for spectrophotometric determination of the p-AAP content in its pure form and in different pharmaceutical preparations with p-AAP. The stoichiometric composition of the reaction was found to be n(p-AAP)∶n(bromine)=1∶3. The effects of pH and time on the spectra of p-AAP-bromine redox reaction product were studied. The interference of different additives on the measured spectra of the obtained product was also studied. The results obtained by the present method were compared with those obtained by the standard method. The F- and t- test values were calculated for both of the applied procedures and they met a confidence level of 99%. The proposed procedure actually needs no separation of these drugs from their sources before analysis and was unaffected by interference of other phenolic compounds. The proposed method is simpler and faster than the repoeted ones.     

Flow Injection Spectrophotometric Determination of Dipyrone in Pharmaceutical Formulations Using Fe(III) as Reagent

A flow injection spectrophotometric procedure with symmetric merging zones for dipyrone determination in pharmaceutical formulations is proposed. The determination is based on the formation of a blue complex (monitored at a wavelength of 642 nm) yield in the complexation reaction of dipyrone with Fe(III) in acid medium. Under optimum conditions, a calibration curve was obtained from 3.5 to 281 mg L^?1 with a detection limit of 2.8 mg L^?1 and the samples throughput was 80 h^?1. The analytical results obtained for commercial formulation samples by applying the proposed method were in good agreement with labeled values and those obtained by a comparative procedure at a 95% confidence level.     

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。     

Spectrophotometric Method for the Rapid Determination of Microgram Amounts of Ethionamide

Abstract

Spectrophotometric Method for the Rapid Determination of Microgram Amounts of Ethionamide

A simple and sensitive method for the determination of microgram amounts of ethionamide is described. Ethionamide is converted to corresponding 2-ethyl-γ-pyridyl thiohydroxamic acid which gives a purple violet colour (Λmax 510 nm) with ferric chloride in acidic medium. This forms the basis for the quantitative determination of ethionamide in its pure form and in tablet form. The influence of substrates, commonly employed as excipients, is studied. An attempt has been made to determine ethionamide in the presence of other antitubercular drugs.     

Kinetic Spectrophotometric Determination of Acetaldehyde

ABSTRACT

A method for determination of trace quantities of acetaldehyde based on its inhibition effect on the malachite green-sulfite reaction is described. The reaction is monitored spectrophotometrically by measuring the decrease in absorbance at 613 nm by a fixed time method of 60 seconds. The method allows the determination of acetaldehyde in the range of 0.2-10 μg/ml. The limit of detection was 0.1 μg/ml and the relative standard deviation for ten determinations of 2 μg/ml acetaldehyde was 1.8%. The method is applied to the determination of acetaldehyde in chemical industrial waste water with satisfactory results.     

Determination of Riboflavin Using Flow Injection Inhibitory Chemiluminescence

ABSTRACT

A new flow injection method for the determination of riboflavin based on the inhibition of the intensity of chemiluminescence (CL) from the luminol-K₃Fe(CN)₆ system is described. While riboflavin mixed with K₃Fe(CN)₆, by the fast oxidation reaction between riboflavin and K₃Fe(CN)₆, K₄Fe(CN)₆ was generated, which then inhibited the CL reaction of K₃Fe(CN)₆ and luminol in alkaline aqueous solution. The CL emission was correlated with the riboflavin concentration in the range from 0.032 to 100 μg·ml?¹, and the detection limit was 0.01 μg·ml?¹ (3σ). A complete analysis could be performed in 2 min with a relative standard deviation of less than 2.2%. The influence of foreign species was studied and the method has been applied successfully to the determination of riboflavin in pharmaceutical samples, the recovery was from 98.0% to 102%.     

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.     

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。     

Flow Injection Method for Sulphide Determination Using an Organic Mercury Compound

Abstract

A simple flow injection analysis method is described for the determination of soluble sulphide, based on the complexation of sulphide with p-hydroxymercurbenzoic acid, in the presence of dithizone used as an indicator. The reaction is very rapid, with a sampling rate of 90/hr. and requires a very short length post injection reaction coil. The detection limit and precision are 0.01 mM and 0.7%, respectively.