Permanganate In Acid Medium Research Articles

과망간산포타슘에 의한 산화에 바탕을 둔 아미노글리코사이드 항생제의 분광광도법적 정량

A rapid, simple and sensitive validated spectrophotometric methods have been described for the assay of neomycin and streptomycin either in pure form or in pharmaceutical formulations. The proposed methods were based on the oxidation of the studied drugs by a known excess of potassium permanganate in acidic medium and estimating the unreacted permanganate with amaranth dye (method A), acid orange II (method B), indigocarmine (method C), and methylene blue (method D), in the same acid medium at a suitable lmax

Colorimetric microdetermination of captopril in pure form and in pharmaceutical formulations

A simple, rapid, accurate, precise and sensitive colorimetric method for the determination of captopril (CAP) in bulk sample and in dosage forms is described. The method is based on oxidation of the drug by potassium permanganate in acidic medium and determination of the unreacted oxidant by measuring the decrease in absorbance for five different dyes; methylene blue (MB); acid blue 74 (AB), acid red 73 (AR), amaranth dye (AM) and acid orange 7 (AO) at a suitable λ max (660, 610, 510, 520, and 485 nm), respectively. Regression analysis of Beer's plots showed good correlation in the concentration ranges (0.4–12.5, 0.3–10, 0.5–11, 0.4–8.3 and 0.5–9.3 μg ml −1), respectively. The apparent molar absorbtivity, Sandell sensitivity, detection and quantitation limits were calculated. For more accurate results, Ringbom optimum concentration ranges were 0.5–12, 0.5–9.6, 0.6–10.5, 0.5–8.0 and 0.7–9.0 μg ml −1, respectively. The validity of the proposed method was tested by analyzing in pure and dosage forms containing CAP whether alone or in combination with hydrochlorothiazide. Statistical analysis of the results reflects that the proposed procedures are precise, accurate and easily applicable for the determination of CAP in pure form and in pharmaceutical preparations. Also, the stability constant was determined and the free energy change was calculated potentiometrically.

Development of Time-Resolved Chemiluminescence for the Determination of Antu in River Water, Wheat, Barley, and Oat Grain Samples

A novel chemiluminescence method for the determination of antu has been developed based on the reaction between potassium permanganate in acid medium with this rat-poison in the presence of formaldehyde as an emission enhancer. The main feature of the system used is that the recording of the whole chemiluminescence intensity-vs-time profiles can be obtained, using the stopped-flow technique in a continuous-flow system. This enables the use of three quantitative parameters adjustable via software settings, one of them a typically kinetic parameter, such as rate of the light-decay reaction, and the others conventional parameters, such as maximum emission intensity and total emission area, which are proportional to the analyte concentration. The optimum chemical conditions for the chemiluminescence emission were investigated. The effect of common emission enhancers, such as formic acid, formaldehyde, glutaraldehyde, acetaldehyde, quinine, fluorescein, rhodamine B, and rhodamine 6G, was studied. The parameters selected were sulfuric acid 4.0 mol L(-)(1), permanganate 0.1 mmol L(-)(1), and formaldehyde 1.0 mol L(-)(1). The calibration graphs obtained with each one of the measurement parameters were linear for the concentration range from 0.05 to 3.00 microg mL(-)(1). The detection limits ranged from 0.005 to 0.010 microg mL(-)(1), and RSD values (n = 10) of 0.99-1.79% at a 0.30 microg mL(-)(1) concentration level and 1.71-2.22% at a 1.0 microg mL(-)(1) concentration level were obtained. The present chemiluminescence procedures were applied to the determination of antu in different kinds of samples, such as river water, wheat, barley, and oat grain samples. Recovery values not significantly different from the spiked amount were found for these determinations.

Flow‐injection–chemiluminescence method for the determination of penicillin G potassium

The degradation product of penicillin G potassium can react with potassium permanganate in acidic medium and produce chemiluminescence, which is greatly enhanced by formaldehyde. The optimum conditions for this chemiluminescent reaction were studied in detail using a flow-injection system. The experiments indicated that under optimum conditions, the chemiluminescence intensity was linearly related to the concentration of penicillin G potassium within the range 1.0 x 10(-7)-1.0 x 10(-5) g/mL, with a detection limit (3sigma) of 7 x 10(-8) g/mL. The relative standard deviation was 1.0% for 4.0 x 10(-7) g/mL penicillin G potassium solution (n = 11). This method has the advantages of simple operation, fast response and high sensitivity. The method was successfully applied to the analysis of penicillin G potassium in raw medicines.

Chemiluminometric determination of propranolol in an automated multicommutated flow system

In this work, a fully automated analytical methodology for the chemiluminometric determination of propranolol hydrochloride in pharmaceutical preparations is proposed. The developed procedure was based on the oxidation of propranolol by potassium permanganate in acidic medium and was implemented in a multicommutated flow system. The combined automated actuation of syringe pumps and two-way solenoid valves, under computer control, assured a high versatility in terms of sample and reagent manipulation and an effective run-time control of all analytical parameters, including a time-based insertion that enabled a significant solutions saving and the exploitation of different strategies for sample/reagent mixing. The calibration graph was linear over the range 20–150 mg l −1 of propranolol hydrochloride with a relative standard deviation lower than 1.6% ( n = 7). The results were in agreement with those obtained by the reference procedure with a relative deviation between −3.8 and 3.7% and a sampling rate of about 27 samples h −1.

Molecular imprinting–chemiluminescence sensor for the determination of brucine

The brucine-imprinted polymer was synthesized and the binding characteristic of the imprinted polymer to brucine was evaluated by equilibrium binding experiments. Using the imprinted polymer as recognition material, a new chemiluminescence (CL) sensor for the determination of brucine was developed based on the CL reaction of brucine with potassium permanganate in acidic medium. The sensor displayed high selectivity and high sensitivity. The linear response range of the sensor was from 5.0 × 10 −9 to 1.0 × 10 −6 g/mL ( r = 0.9981) and the detection limit was 2 × 10 −9 g/mL. The relative standard deviation for the determination of 1.0 × 10 −7 g/mL brucine solution was 2.6% ( n = 9). The sensor was applied to the determination of brucine in urine samples with satisfactory results.

Determination of Phenol by Preconcentration‐Direct Chemiluminescence in a FIA Assembly

The determination of phenol in water samples is proposed with the aid of a flow‐injection system. The analytical procedure is based on the direct chemiluminometric emission by oxidation of the analyte with potassium permanganate in acidic medium. The flow assembly is provided with a solid‐phase reactor filled with a resin type XAD‐4 for analyte preconcentration. A large study of potential interferences, namely, amino acids reaching water through degradation of organic matter; metals and inorganic metal ions typically present in water interfering with the CL emission of the parent compound, was performed. The calibration graph was linear over the phenol concentration range 1.0–20.0 ng mL−1; the LOD was 5.0 ng mL−1. Finally, the method was applied to the determination of phenol in waste‐ and groundwater.

Molecular imprinting-chemiluminescence determination of trimethoprim using trimethoprim-imprinted polymer as recognition material

A new molecular imprinting-chemiluminescence method for the determination of trimethoprim was developed, in which trimethoprim-imprinted polymer was used as the molecular recognition material and the CL reaction of trimethoprim with potassium permanganate in acidic medium was used as the detection system. The CL intensity responds linearly to the concentration of trimethoprim within the 5.0 x 10(-8)-5.0 x 10(-6) g mL(-1) range (r= 0.9983) with a detection limit of 2 x 10(-8) g mL(-1). The relative standard deviation for the determination of 1.0 x 10(-7) g mL(-1) trimethoprim solutions is 4.8% (n= 9). The method has been applied to the determination of trimethoprim in pharmaceutical preparations and body fluids, and satisfactory results were obtained.

New flow-multicommutation method for the photo-chemiluminometric determination of the carbamate pesticide asulam

This paper deals with a straightforward automated method for the determination of asulam in water based on the use of a flow manifold including three computer-controlled solenoid valves. The method involves irradiating on an aqueous solution of asulam in glycine buffer at pH 8.3 with UV light during 90s, then follows the oxidation with potassium permanganate in a sulphuric medium and chemiluminescence-based detection of the resulting photoproducts. The limit of detection thus achieved is 40μgl−1. The detector response is linear up to a 5mgl−1 asulam concentration and the throughput is 30samplesh−1. In parallel tests, oxidation with alkaline ferricyanide was also assessed and the results compared (sensitivity, selectivity and reproducibility) with those from oxidation with potassium permanganate in acidic medium. The use of a flow based on solenoid valves results in substantial reagent savings and constitutes a further extension of clean chemistry procedures. To the authors’ knowledge, this is the first chemiluminescence-based determination of asulam and also the first based on multicommutation analysis.

Micelles in Physical Chemistry Laboratory. Surfactant Catalyzed Oxidation of Glycine by Acidic Permanganate

미셀 촉매 작용은 이론과 실험 화학 교과내용에서 중요한 부분이다. 산성 용액에서 도데실황산 나트륨(SDS)을 촉매로 한 글리신과 과망가니즈산 칼륨의 반응은 미셀 촉매 작용을 보여주는 반응속도론적 실험으로 적합하며, 고등학교와 대학 학부과정의 물리화학실험에서 사용할 수 있다. 본 연구에서는 이 반응이 계면활성제 존재하에서 반응속도가 빨라지는 것을 관찰하기 위하여 SDS를 넣지 않은 경우와 넣은 경우 모두 실험을 진행하였고, 얻어진 k를 [SDS]에 대하여 도시하였다. SDS의 임계 미셀 농도 이하에서부터 계면활성제에 의한 촉매 효과가 관찰되었는데, 이 선-미셀 촉매 효과는 양의 협동효과에 의한 것임을 알 수 있다. 얻어진 양의 협동지수(n)는 2.37이다. 또한 기질과 산화제의 농도에 따른 반응속도 변화도 논의하였다. 반응은 유사 일차 반응으로 진행되었으며, 글리신과 과망가니즈산 이온의 농도에 각각 일차 반응으로 나타나 전체 반응 차수는 이차 반응이었다. 반응 시간은 3~4시간으로 한 실험 시간에 몇 개의 실험 데이터를 얻을 수 있다. 용액 제조와 실험 과정에 대해서 자세히 기술하였으며, 또한 계면활성제에 의한 촉매 작용의 이론도 논의하였다. Micellar catalysis is an essential part of theoretical and experimental curricular. The sodium dodecylsulfate (SDS) catalyzed reaction between glycine and potassium permanganate in acidic medium is an ideal kinetic experiment for the secondary and undergraduate physical chemistry laboratory, to show the effect of micellar catalysis on rate of the reaction. The reaction is conducted both with and without SDS to observe the rate enhancement in the presence of surfactant. To show surfactant catalysis a plot between k and [SDS] is plotted. As surfactant catalysis is observed even before the critical micelle concentration of SDS, this pre-micellar catalysis can be understood in the light of positive co-operativity. The value of positive cooperative index (n) has been found to be 2.37. Further, dependence of the reaction rate on substrate and oxidant concentrations is also discussed. The reaction follows pseudo-first-order kinetics. The overall reaction is second order, with first-order dependence on both glycine and permanganate concentrations. The theory of surfactant catalysis is also discussed. With the conditions specified in the experiment, total reaction times are in 3~4 hours lab session, thus allowing several data sets to be acquired in a single laboratory period. Preparation of solutions and procedure is also given in detail.

Flow‐Injection Chemiluminescent Determination of Thiamine in Pharmaceutical Samples by On‐line Photodegradation

A simple, sensitive, and precise method for the determination of thiamine hydrochloride in a flow‐injection system is described. The method is based on the UV irradiation of thiamine in acid medium. Then, the photo‐fragments are oxidized by permanganate in acid medium, and the resultant chemiluminescent intensity is measured. The optimum conditions for the photoreaction and for the chemiluminescence emission were investigated. The method allows the determination of thiamine, over the range 0.05(LOD)–84 mg · l−1, with a throughput of 30 h−1, and a RSD (n, 20) at 20 and 0.5 mg · l−1 of the thiamine level of 2.5 and 1.3%, respectively. The method was applied to pharmaceutical preparations.

Determination of peracetic acid and hydrogen peroxide in the mixture

Iodometric and permanganometric titrations were used for determination of peracetic acid and hydrogen peroxide (H2O2) in the mixture. Two procedures were described and compared. Titrations could be done in only one vessel, in the same reaction mixture, when iodometric titration of peracetic acid was continued after the permanganometric titration of H2O2, (procedure A). Peracetic acid and H2O2, as oxidizing agents, reacted with potassium iodide in an acid medium, evolving iodine. This reaction was used for the quantitative iodometric determination of total peroxide in procedure B. H2O2 reacted with potassium permanganate in acid medium, but peracetic acid did not react under the same conditions. That made possible the selective permanganometric determination of H2O2 in the presence of peracetic acid. The procedure B was performed in two titration vessels (KV = 3.4% for peracetic acid, 0.6% for H2O2). The procedure A for iodometric determination of peracetic acid in one titration vessel after permanganometric titration of H2O2 was recommended (KV = 2.5% for peracetic acid, 0.45% for H2O2).

Chemiluminescence determination of thioridazine hydrochloride by flow-injection analysis

Hydrogen peroxide, potassium permanganate, potassium dichromate, potassium hexacyanoferrate(III), cerium(IV) sulphate and sodium peroxidisulphate have been tested as potential reagents for chemiluminescence generation from the oxidation of phenothiazine derivatives. Only with potassium permanganate in acidic medium were satisfying results achieved. A total of 13 different phenothiazine derivatives produce luminescence of different intensities on oxidation. Thioridazine hydrochloride was chosen to develop a rapid and simple method for its determination in pharmaceutical formulations. The limit of detection is 1.2×10 −6 mol l −1, and 110 samples per hour can be determined.

Kinetics and mechanism of the oxidation of L-?-amino-n-butyric acid by permanganate in acid medium

Kinetics and mechanism of the oxidation of L-?-amino-n-butyric acid by permanganate in acid medium

Kinetic study of the oxidation of L‐phenylalanine by potassium permanganate in acid medium

AbstractThe kinetics of permanganate oxidation of L‐phenylalanine in acid medium at a constant ionic strength has been investigated spectrophotometrically. An autocatalytic reaction was observed being autocatalyzed by a soluble form of Mn(IV).The reaction appears to involve a parallel consecutive reaction process in which Mn(IV) is formed as an intermediate and Mn(II) as a reaction product. A tentative mechanism consistent with the kinetics is discussed. © 1995 John Wiley & Sons, Inc.

Flow injection chemiluminometric determination of epinephrine, norepinephrine, dopamine and L-dopa.

A method is proposed for the determination of 0.0500-1.00 microgram ml-1 of epinephrine and L-dopa and 0.100-1.00 micrograms ml-1 of norepinephrine and dopamine by their chemiluminogenic oxidation with potassium permanganate in acidic medium, in the presence of formaldehyde, which greatly improves the sensitivity. Flow injection allows the measurement of 80 solutions per hour. The method was also optimized for a continuous-flow system. Comparative results from numerous organic compounds proved the necessity for electron-donating groups on the benzene ring for sensitive chemiluminescent characteristics.

One-Pot Oxidation and Nitrosation of β-Alkanolamines with KMnNO4-NaNO2. A Convenient Preparation of β-Ketonitrosamines

Abstract The oxidation and nitrosation of β-alkanolamines to the corresponding β-ketonitrosamines is reported. The oxidation is carried out with potassium permanganate in acidic medium, followed by nitrosation of the protonated aminoketone, with sodium nitrite, to the corresponding β-ketonitrosamine.

Gasometric determination of formic and oxalic acids

A method for the determination of formic and oxalic acids ( > 2.5 μmol) is based on the catalytic dehydration of formic and oxalic acids with acetic anhydride and measurement of the volume of liberated carbon monoxide. Formic acid (0.8–4.0 mg) can be determined in admixture with oxalic acid if the latter is first oxidized with permanganate in acidic medium. The error of a single determination of one acid does not exceed 3% (95% confidence).

ChemInform Abstract: Kinetics and Mechanism of Sulphite Oxidation by Permanganate in Acid Medium.

AbstractThe kinetics of the title reaction have been investigated in the pH range 5.4‐6.5 at temp. between 288 and 303 K and an empirical rate law is given.

Kinetics and Mechanism of Sulphite Oxidation by Permanganate in Acid Medium

Kinetics and Mechanism of Sulphite Oxidation by Permanganate in Acid Medium