Kinetic Spectrophotometric Method Research Articles

The Quantitative Determination of Etonium by the Enzymatic Kinetic-Spectrophotometric Method

The use of the cholinesterase enzyme as a component of the analytical system has made it possible to develop a new kinetic-spectrophotometric method, which is alternative to the pharmacopoeial method, for determining the quaternary ammonium salt – ethonium in the substance and a dosage form. This method is characterized by high sensitivity and specificity, and is relatively cheap. The relative standard deviation of the procedure does not exceed 2.7 %, and the limit of quantification is 17 ng mL–1.

A transformative oxidation process involving silver-based catalysis of para aminobenzyl alcohol for transposing a pollutant into a resource

ABSTRACT A kinetic-spectrophotometric method has been devised to analyze the oxidation reaction of Para-aminobenzyl alcohol [PABAlc] catalyzed by Ag (I). PABAlc is used in numerous fields of pharmaceutical and medicinal chemistry as intermediates. The harmful effects of PABAlc cannot be overlooked in spite of its manifold applications. The toxicity of PABAlc may lead to allergic reactions, serious eye damage, respiratory tract infections amongst few. It became utmost important to formulate a method to establish the presence of PABAlc in a particular sample of water in order to circumvent its proximity to common people. In our work, we have provided an insight to an oxidation process using PABAlc as substrate catalyzed by Ag (I) ions besides proposing a reaction mechanism of the reaction under study with substantial data in the form of different thermodynamic parameters like activation energy (55 kJ/mol−1), temperature coefficient (1.92), enthalpy of activation (52.89 kJ/mol−1), alongside deets related to various effects of oxidant, substrate, catalyst, temperature, pH, ionic strength, and so on, on reaction kinetics. Additionally, the product formed in the proposed mechanism has its commercial importance in the field of pharmacy, dyes, and so on, sufficient enough to put forward a rationale for the investigations.

Development and validation of a kinetic-spectrophotometric method for the trace determination of 2-methyl-4-chlorophenoxyacetic acid in baby teas and baby food samples using solid phase extraction followed by high-performance liquid chromatography

Development and validation of a kinetic-spectrophotometric method for the trace determination of 2-methyl-4-chlorophenoxyacetic acid in baby teas and baby food samples using solid phase extraction followed by high-performance liquid chromatography

Kinetic Spectrophotometric Method for Determination of Ceftriaxone in Bulk and Vials

Kinetic Spectrophotometric Method for Determination of Ceftriaxone in Bulk and Vials

Kinetic study of the hydrolysis of ester with mineral acid by spectrophotometer at different temperature

To determine the kinetic parameters and activation energy of the hydrolysis of ethyl acetate with hydrochloric acid monitored by spectrophotometry. The first order fits were automatically drawn and the values of the first order rate constants (k) were calculated using standard equations as part of the program. Acidic hydrolysis of ethyl acetate is essentially an irreversible and first order reaction whereas alkaline hydrolysis is an irreversible and second order reaction. Rate of reaction is the change in the number of molecules of reacting species per unit volume per unit time. In this hydrolysis of ethyl acetate with hydrochloric acid to accelerate the reaction mixture. A simple and sensitive kinetic spectrophotometric method presented for the determination of rate constant, order of reaction and activation energy. This method based on a kinetic investigation of ethyl acetate and hydrochloric acid at 35°C and 45°C temperature. The reaction followed spectrophotometrically by measuring the absorbance at 500 nm as a function of time. The initial rate and fixed time methods utilized for construction of calibration graphs successfully for the determination of rate constant, order of reaction and activation energy. The rate constant after calculation from the graphs was approximately k1 ≈ 0.00260 Sec-1 k2 ≈ 0.00322 Sec-1 by titration and spectrophotometric method respectively, order of reaction found to be first order and the activation energy for this reaction is 17.44 kJ/mol. One factor that influences the absorbance of a sample is the concentration (c). As the concentration increases, more radiation is absorbed and the absorbance increase. Therefore, the absorbance is directly proportional to the concentration.

Toward the Development of an Electromechanical Ion-Specific Conveyer Belt

Bromide (Br−) is ubiquitous both in natural waters and those impacted by anthropogenic activities, such as, the discharge of treated or untreated wastewaters, releases from coal-fired power plants and hydraulic fracturing operations, and sea water intrusion. The development of methods for the extraction and purification of Br−, particularly from Br− -rich brines, is regarded as of great economic interest owed to the uses of bromine in many industrial processes. In fact, the removal of Br- from drinking water is beneficial from a public health perspective, as it can lead to the formation of regulated disinfection byproducts (DBPs) during water treatment. Although various alternatives have recently been proposed to remove halide anions, such as bromide, from drinking water, none of them have proven sufficiently effective for large-scale application (see e.g. Ref. 1).The present contribution describes a strategy for the removal and purification of bromide from an aqueous solution containing chloride in amounts that closely mimic those found in natural brine sources. As will be described, this tactic relies on the selective electrosorption of Br− on Au, an inert metal electrode material from such a synthetic brine, and its subsequent desorption into a second aqueous solution devoid of Br−.The all glass multi compartment cell employed for these experiments ‘shown schematically in the figure above consists of a central cylindrical cup filled with 0.01 HClO4 supporting electrolyte, which houses the reference, RE, and counter electrodes connected on either side to two identical cups of smaller diameter, C1 and C2 are separated from the central cup by glass frits so that diffusion between C1 and C2 is negligible. At the start of a regular experiment, C1 is filled with a solution containing 28 mM KCl and 12.5 mM KBr, the synthetic brine, in the supporting electrolyte, and C2 is filled with only supporting electrolyte. In the initial stage of this protocol, a gold foil is immersed in C1, which together with the RE and CE would form a conventional 3-electrode cell and a potential of 1.3 V vs RHE is then applied to the Au foil using a potentiostat to induce anion adsorption for ca.10 s. which is sufficient for Br-(aq) and Cl-(aq) to achieve their equilibrium coverages under the specific conditions of the experiment, as represented by the blue arrow. Based on the results of independent optical measurements, Br-(aq) would be the predominant ion adsorbed on the Au surface at this high potential. Subsequently, the Au foil is emersed from the solution without disconnecting the potentiostat, immersed into C2, and a potential of 0.2 V applied, which is just positive of the onset of hydrogen evolution but negative enough for adsorbed Br- to fully desorb, as represented by the red arrow. This process is then repeated tens of times, at the end of which the composition of the solution in C2 is analyzed using the methylene blue (MB) spectroscopic method described by Uraisin, et al. (2) to determine specifically Br-(aq), and a slightly modified Mohr’s turbidimetry technique, which employs K2CrO4 as the indicator, to determine the total amount of Br-(aq) and Cl-(aq).Four independent runs involving 50 to 75 sequential transfers were performed in order to assess the efficiency of this process, and found to yield an increase in the Br-(aq) concentration from an initial 30% in C1, up to higher than 75% in C2. Overall, the efficiency of this process can be increased by a corresponding increase in the area of the electrode. Alternatively, one can envision a continuous process involving a segmented electrode in the form of a belt and appropriate potential controls, that would be continuously emersed and immersed into C1 and C2, acting as a virtual ionic conveyer. Various aspects of this unique technology and its prospects for large scale implementation will be discussed. Acknowledgements This work was supported by a grant from NSF, CHE-1412060 References Sanchez-Polo, J. Rivera-Utrilla, E. Sahli, U. von Gunten, Ag-Doped Carbon Aerogels For Removing Halide Ions In Water Treatment, Water Res., 41, 2007,1031-1037Uraisin, T. Takayanagi, M. Oshima, D. Nacapricha, S. Motomizu, Kinetic-Spectrophotometric Method For The Determination Of Trace Amounts Of Bromide In Seawater, Talanta, 68, 2006, 951-956 Figure 1

Expression of paraoxonase 1 in HEK293 cells and its effect on lactonase and arylesterase activity in samples containing human serum and/or prooxidant or antioxidant agents - a preliminary study

Expression of recombinant paraoxonase 1 (PON1) in the human embryonic kidney (HEK293F) cell line was evaluated. Two recombinant human PON1 proteins were investigated: PON1-Fc, which has an Fc-tag on its C-terminal, and His-PON1-Fc, which has an Fc-tag on its C-terminal and histidine on its N-terminal. The influence of high and low-density lipoproteins, copper ions, iron ions, and thiolactone homocysteine, on arylesterase and lactonase activities of PON1 in human serum was examined. Two activities of PON1, arylesterase and lactonase, were measured using earlier elaborated kinetic spectrophotometric method with temperature control at 37°C using the water thermostated cuvette holder. It was demonstrated that the HEK293F expression platform is useful for obtaining recombinant human PON1 protein. Also, addition of high-density lipoprotein increased serum arylesterase and lactonase activity of PON1 to a greater extent than the addition of PON1-Fc or HisPON1-Fc recombinant proteins. In contrast, the addition of high-density lipoprotein to samples containing PON1-Fc or His-PON1-Fc did not increase PON1 activities, while low-density lipoprotein, copper ions, and iron ions, depressed PON1 arylesterase and lactonase activity. Obtained results indicated that it may be advantageous to stimulate PON1 activities rather than supplement with endogenous PON1 protein and HDL, which could be an interesting direction for further study. Furthermore, the work has highlighted some potential research directions for the use of PON1 as a therapeutic molecules. Nevertheless, the study had some limitations and should therefore be treated as a preliminary study.

Synthesis and catalytic activity of Cu (II) complex with 4-phenyl 2, 6-di (thiazol-2-yl) pyridine in the oxidation of para-aminophenol

In the present work the synthesis of 4-phenyl-2, 6-di (thiazol-2-yl) pyridine copper chloride (abbreviated as Cu-DTPy) complex using copper (II) chloride and 2, 6-di (thiazol-2-yl) pyridine has been carried out. The complex has been specified by UV-Vis, FT-IR, CHNS and ESI-MS methods of analysis. The synthesized copper complex has been used as catalyst in the oxidation of p-aminophenol using hexacyanoferrate (III) ions as an oxidant in aqueous alkaline medium by kinetic-spectrophotometric method. This experimental work was carried out at optimum pH 11.0 and temperature 25ºC. The variation of effect of concentration of p-aminophenol (abbreviated as PAP), hexacyanoferrate (III) ions, and Cu-DTPy catalyst on reaction rate has been studied. Thermodynamic parameters such as free energy of activation, activation energy, enthalpy and frequency factor have been evaluated with the change in rate of the reaction at four disparate temperatures i.e. 25-40ᵒC. The oxidation products have been identified by FT-IR and ESI-MS spectroscopic analytical techniques. The major product of this reaction is NN’-bis-(p-hydroxyphenyl)-2-hydroxy-5-amino-1,4-benzoquinone di-imine. Thus, this method is highly efficient and environmentally safe to remove PAP from polluted water resources.

Kinetic Spectrophotometric Determination of Ascorbic Acid by Using Phenanthroline Agent in Eruca sativa

Ascorbic acid is used for treatment in hypovitaminosis, nutritional deficiency, scurvy, gingivitis, Barlow and Basedow diseases. In this study, a simple and sensitive kinetic spectrophotometric method was developed for the determination of ascorbic acid in Eruca sativa. The rate of formation of the product formed as a result of the reaction of ascorbic acid with iron (III) sulfate and phenanthroline reagents was determined by measuring the absorbance at 510 nm wavelength at 5 minute intervals for 60 minutes. The measurement curve prepared from standard ascorbic acid solution is linear in the concentration range of 4.0-6.0 mg/mL. The regression equation obtained from the graph of logarithms of molar concentrations versus logarithms of slopes was found as log (rate) = 2.5721 logC - 9.461 (r=0.9999) according to the initial rate method. The developed method was applied to Eruca sativa samples and the amount of ascorbic acid in fresh leaves was found to be 72.80 mg/100 g.

Kinetic and Mechanistic Study of Oxidative Degradation and Detoxification of Fast Yellow Azo Dye Using Surfactant Assisted Ir-Ni Bimetallic Nanocatalyst

Aim: Catalytic degradation of azo dye. Background: Azo dyes are toxic agents and pollutants and the degradation of these dyes has an important application in the treatment of textile industry wastes. Catalytic decolorization of fast yellow dye by hexacyanoferrate (III), abbreviated as HCF(III) using polyvinylpyrrolidone abbreviated as PVP stabilized Ir-Ni bimetallic nanocrystals has been evaluated by kinetic spectrophotometric method at 440nm wavelength of the reaction mixture. Methods: The impact of various operational factors such as fast yellow dye abbreviated as [FY], oxidant [HCF(III)] ions, promoter iridium-nickel bimetallic nanoparticles abbreviated as [(Ir-Ni)] BMNPs, and solution pH on the rate of the reaction have been examined. Results: The results represent that the reaction follows first -order kinetics model with respect to [oxidant] at optimum pH 8 and fix temperature 40±0.1◦C. Thermodynamic parameters such as activation energy (Ea), enthalpy (ΔH#), entropy (ΔS#), frequency factor (A), and free energy of activation (ΔF#) have been evaluated by examining the reaction rate at four temperatures i.e. 40⁰C, 45⁰C, 50⁰C, and 55⁰C. On the basis of experimental outcomes, an appropriate mechanism involving complex formation has been proposed. Conclusion: Analytical techniques such as UV-Vis spectroscopy, FTIR, and LCMS of degraded products represent the formation of easier and less harmful compounds.

Development and Validation of Kinetic Spectrophotometric Method for Determination of Venlafaxine Hydrochloride

Development and Validation of Kinetic Spectrophotometric Method for Determination of Venlafaxine Hydrochloride

Decreased Activity of Erythrocyte Catalase and Glutathione Peroxidase in Patients with Schizophrenia.

Background and Objectives: Catalase and glutathione peroxidase (GPx) are important antioxidant enzymes that break down hydrogen peroxide (H2O2) in order to control its intracellular concentration, thus enabling its physiological role and preventing toxic effects. A lack or disruption of their function leads to the accumulation of hydrogen peroxide and the occurrence of oxidative stress. Accumulating studies have shown that the activities of key antioxidant enzymes are impaired in patients with schizophrenia. Since the published results are contradictory, and our previous studies found significantly higher erythrocyte superoxide dismutase (SOD) activity in patients with schizophrenia, the aim of this study was to determine the activity of enzymes that degrade hydrogen peroxide in the same group of patients, as well as to examine their dependence on clinical symptoms, therapy, and parameters associated with this disease. Materials and Methods: Catalase and GPx activities were determined in the erythrocytes of 68 inpatients with schizophrenia and 59 age- and gender-matched healthy controls. The clinical assessment of patients was performed by using the Positive and Negative Syndrome Scale (PANSS). The catalase activity was measured by the kinetic spectrophotometric method, while the GPx activity was determined by the commercially available Ransel test. Results: Erythrocyte catalase and GPx activities were significantly lower (p < 0.001 and p < 0.01, respectively) in subjects with schizophrenia than they were in healthy individuals. Lower catalase activity does not depend on heredity, disease onset, the number of episodes, or disease duration, while GPx activity showed significant changes in patients who had more than one episode and in those who had been suffering from the disease for over a year. Significantly lower catalase activity was noted in the PANSS(+/−) group in comparison with the PANSS(+) and PANSS(−) groups. The lowest catalase activity was found in subjects who were simultaneously treated with first- and second-generation antipsychotics; this was significantly lower than it was in those who received only one class of antipsychotics. Conclusion: These results indicate the presence of oxidative stress in the first years of clinically manifested schizophrenia and its dependence on the number of psychotic episodes, illness duration, predominant symptomatology, and antipsychotic medication.

A comparative study of the effect of phenothiazine derivatives and their S-oxides on cholinesterase investigated by a new kinetic spectrophotometric method

Aim. To develop a new kinetic spectrophotometric method for determining acetylcholinesterase (AChE) inhibitors – phenothiazine antipsychotic drugs (PhT) and their sulfoxide metabolites (S-oxides) without adding an exogenous catalyst to obtain a chromogenic agent.Materials and methods. The bases of S-oxides of promethazine (PMZ), chlorpromazine (CPM) and thioridazine (THZ) were obtained by oxidizing the corresponding PhT hydrochlorides with diperoxyadipic acid. The structure of the S-oxides of the corresponding PhT synthesized was proven by melting points, spectral characteristics (1H NMR and IR methods) and oscillopolarography results. 1H NMR spectra were recorded on a Varian XL-200 spectrometer. IR spectra were recorded within the range of 4000-400 cm–1 on a SPECORD M-80 spectrometer (Zeiss, Jena, Germany). To register polarograms, a “PO 03 CLA” oscillopolarograph with a three-electrode cell was used. The purity of S-oxides was determined by the high-performance liquid chromatography method on a Zorbax SB, C-18 (250 × 4.6) mm column. Measurements of absorbance of solutions were performed in a 1 cm cuvette on an Evolution 60S UV-Visible Thermo-Scientific Spectrophotometer (USA) (λ = 358 nm).Results and discussion. Acetylcholine (ACh) was found to mimic the activity of peroxidase; based on it, a spectrophotometric system containing ACh–H2O2–p-Ph for a sensitive and selective assessment of the AChE activity and determination of its inhibitors was developed. According to the plots of inhibition efficiency vs inhibitors concentration, the inhibiting ability of chlorpromazine, promethazine and thioridazine and their S-oxides was determined. The IC50 values of CPM, PMZ and THZ and their metabolites in relation to the AChE activity were estimated as 11 ng mL−1 (CPM) and 1.8 ng mL−1 (CPM S-oxide), 17 ng mL−1 (PMZ) and 2.5 ng mL−1 (PMZ S-oxide) and 27 ng mL−1 (THZ 2S,5S-dioxide). The results obtained indicate that S-oxides of the corresponding PhT are selective and potent inhibitors of AChE. The values of the inhibition efficiency obtained for S-oxides of PhT derivatives were an order of magnitude lower than those of the corresponding PhT derivatives.Conclusions. The spectrophotometric method proposed without the addition of other exogenous catalysts holds promise for the on-site determination of PhT antipsychotics and can be additionally used for sensory applications in areas related to environmental protection and food safety, as well as in the chemical-toxicological analysis.

Application of the enzymatic method for the quantitative determination of dequalinium chloride in lozenges

Aim. To develop a new kinetic spectrophotometric enzymatic method suitable for the quantitative determination of dequalinium chloride in lozenges.Materials and methods. An enzymatic kinetic spectrophotometric method for the quantitative determination of dequalinium chloride in lozenges has been proposed. It is based on the ability of dequalinium chloride to inhibit the enzymatic hydrolysis reaction of acetylcholine by cholinesterase in the presence of the acetylcholine (AСh) excess and H2O2. The degree of inhibition was determined by the kinetic method using two conjugated reactions: ACh perhydrolysis (interaction with an excess of hydrogen peroxide) followed by oxidation with the peroxyacid formed. Peracetic acid formed in situ by the reaction between unreacted ACh and H2O2 interacts with p-phenetidine forming a product, which absorbs at λmax = 354 nm, in the phosphate buffer solution with pH 8.3 at room temperature.Results and discussion. The linear dependence of the calibration graph for the quantitative determination of dequalinium chloride was in the concentration range of 0.2 – 0.8 μg mL–1 (r = 0.999). LOD and LOQ were 0.01 × 10–6 and 0.03 × 10–6 mol L–1, respectively. For the quantitative determination of dequalinium chloride in lozenges, RSD ≤ 2.65 % (accuracy, δ = -1.10…+1.78 %).Conclusions. A new enzymatic kinetic spectrophotometric method has been developed, and its applicability to the quantitative determination of dequalinium chloride in lozenges has been shown. It does not require a complicated treatment of the analyte and a tedious extraction procedure. The method proposed is sensitive enough to determine a small amount of the active pharmaceutical ingredient. These advantages encourage the application of the method proposed in routine quality control of the drugs studied in analytical laboratories.

Ranitidine decreases human sperm motility and vitality and increases the activity of seminal creatine kinase.

Ranitidine (brand name: Zantac), an acid reducer, belongs to histamine-2 receptor antagonists. Since 1981, even though several adverse effects of this drug were reported in the body, still, its effects on human sperm parameters have yet to be confirmed. In this work, we attempted to measure sperm motility, sperm vitality and activity of seminal creatine kinase in the ejaculated human semen (n= 31) in the presence of ranitidine at a range of concentrations (0.1, 0.3, 0.6, 0.9 and 1.2μg/ml) compared with control (without ranitidine). Sperm motility was measured using the Makler counter, whilst sperm vitality was assessed using the Eosin test. Creatine kinase activity was measured using the kinetic spectrophotometric method. Sperm motility (total and progressive) as well as sperm vitality was significantly (p < .05) reduced in the presence of ranitidine in human semen, particularly at the higher tested concentrations (0.6-1.2 μg/ml) compared with the control. On the other hand, creatine kinase activity was significantly increased (p < .05) in the presence of ranitidine at 0.6, 0.9 and 1.2 μg/ml. In conclusion, ranitidine at 0.6-1.2 μg/ml reduced sperm motility and vitality, but increased the activity of creatine kinase in ejaculated human semen.

Kinetic Spectrophotometric Method and Neural Network Model Application for the Quantitation of Epinephrine by Starch-capped AgNPs Sensor in Blood and Urine

Kinetic Spectrophotometric Method and Neural Network Model Application for the Quantitation of Epinephrine by Starch-capped AgNPs Sensor in Blood and Urine

A shipboard method for catalytic kinetic spectrophotometric determination of trace Cu(II) concentrations in seawater using reverse flow injection analysis coupled with a long path length liquid waveguide capillary cell

By using reverse flow injection analysis (rFIA) and a 1.0 m liquid waveguide capillary cell (LWCC), an automatic and sensitive catalytic kinetic spectrophotometric method for on-line monitoring of Cu(II) concentrations in estuarine and coastal waters was established. Cu(II) detection was based on its catalytic effect on glutathione (GSH) oxidation by potassium ferricyanide under acidic conditions. The change in absorbance of potassium ferricyanide at 420 nm was used to monitor the reaction spectrophotometrically. Experimental parameters were optimized using a univariate experimental design approach and it was ensured that the method was free of interference from co-occurring ions such as Fe(Ⅱ), Fe(III), Mn, Zn, Cd, Al, Cr, Ni and Co. The proposed method was shown to have high sensitivity with a detection limit of 0.15 nmol L-1 in a pure water matrix and 0.23 nmol L-1 in a seawater matrix. Linearity was achieved within the range of 0.45–15 nmol L-1 in a pure water matrix and 0.69–10 nmol L-1 in a seawater matrix using a 200 cm reaction coil, while the upper limits can be extended to 40 and 25 nmol L-1, respectively, by using a shorter (100 cm) reaction coil. A high level of Cu(II) recovery was maintained, ranging between 95.2% and 101%. The relative standard deviations (RSDs) of blanks and samples spiked with 5 nmol L-1 Cu(II) standard were 1.52% (n = 13) and 1.10% (n = 13), respectively. The method was confirmed to be free of carry-over effect and a sample throughput of 26 h−1 was achieved. The method was successfully applied to underway and on-board determination of Cu(II) concentrations from a surface transect in the Jiulong Estuary and a vertical profile in the Yangtze Estuary, China, respectively.

Quantification of N-acetylcysteine in drug formulations using inhibitory kinetic spectrophotometric method

Quantification of N-acetylcysteine in drug formulations using inhibitory kinetic spectrophotometric method

Validated green spectrophotometric kinetic method for determination of Clindamycin Hydrochloride in capsules

BackgroundSimple, sensitive, free of organic solvents, kinetic spectrophotometric method has been developed for the determination of Clindamycin Hydrochloride, both in pure form and Capsules. Method is based on reaction of Clindamycin with potassium iodide and potassium iodate in an aqueous medium at (25 ± 2 °C) to produce yellow-coloured tri iodide ions (I3−). The reaction is followed spectrophotometrically by measuring the absorbance at wavelength 350 nm during 40 min.ResultsThe effects of analytical parameters on reported kinetic methods were investigated. Under the optimized conditions, the initial rate and fixed time (at 10 min) methods were used for constructing the calibration graphs. The graphs were linear in concentration ranges 1–20 μg ml−1 with limit of detection of 0.12 and 0.22 μg ml−1for the initial rate and fixed time methods, respectively. The results were satisfactory and the analytical performance for both methods was validated.ConclusionThe proposed methods have been applied to determine the components in capsules with an average recovery of 98.25–102.00% and the results are in good agreement with those found by the reference method.

Trace determination of isoniazid at micro level using kinetic spectrophotometric method

An effective and fairly inexpensive spectrophotometric method for tracing the determination of isoniazid (INH) in pure form, as well as in pharmaceutical formulations, has been developed through the ligand substitution reaction between INH and aquapentacyanoruthenate (II) ion ([Ru(CN)5OH2]3-) in aqueous medium at ?max = 502 nm. The fixed time procedure has been employed under optimum reaction conditions. The calibration equations, relating absorbance measured at 502 nm at fixed times (tn = 2, 5 and 7 min) and cINH in linear range 1.37-27.43 ?g mL-1, were used for the trace determination of INH, which has been reported in the present investigation and are in agreement with official and reported methods. The percentage recovery has been calculated and found to be within the range of 99?101 % in the analysis of different pharmaceutical samples. The results reveal that the use of common recipients as the used additives do not produce any type of interference in the suggested method. The validity of the proposed method was also checked by statistical analysis which agreed with the results obtained using the official method. The present method is very simple, reproducible, sensitive and it can be adopted for trace determination of INH in different samples without using extracting agent.