Formation Of Ion-association Complex Research Articles

Extraction and Determination of Sildenafil Citrate by Spectrophotometry: Classical Versus Factorial Design Optimization

In this work, the complexation and extraction processes of sildenafil citrate (SC) were evaluated by using classical optimization versus factorial design methodology. The selected factors were based on the reaction of sildenafil with methyl orange (MO) as a chromogenic reagent via the formation of ion-association complex in acidic buffer media, followed by extraction with chloroform and quantitatively measured by visible spectrophotometry at λmax of 427 nm. The optimization step was first carried out by classical one-factor-at-a-time (OFAT) from which the extracted results were exploited in the experimental design optimization by using 24-1 fractional factorial and 32 full factorial designs for the chosen variables such as pH, concentration of reagent, reaction time, extraction time and temperature. Results obtained from fractional factorial design 24-1 showed that only the variables pH, MO concentration and their interaction based on analysis of variance (ANOVA) in term of Pareto chart, were statistically significant at 95% confidence level. Under the optimized conditions, the assay method of SC was validated in term of the analytical figures of merit. SC can be determined in concentration range of 0.5-40 µg mL-1 with correlation coefficient of 0.9991, detection limit (S/N) of 0.15 µg mL-1, RSD (n=10) of 1.43%, accuracy as %Erel of -2.23% and mean percent recovery of 97.77±0.87. The proposed method was applied for the determination of SC in commercial medicaments without fear from excipients interferences with the assay procedure.

Use of sodium tetraphenylborate reagent for conductometric titration of Amlodipine Besylate in pure and pharmaceutical forms

Simple, accurate and reliable conductometric method for the quantitative determination of Amlodipine Besylate (AML) in pure form and pharmaceutical formulations using sodium tetraphenylborate (TPB) in aqueous solution at 20°C has been described. The method is based on the formation of ion association complex of cation coming from the cited drug with tetraphenylborate anion and the conductance of the solution is measured as a function of the volume of titrant. Many experimental conditions were evaluated. The described procedure allowed the determination of AML in double distilled water in the range of 0.200-1.000mM. The accuracy of the method is indicated by the excellent recovery 98.60-101.40%, and the precision is supported by the low relative standard deviation < 4.74 %. The method was further applied successively to pharmaceutical formulations with no interference from the excipients, the results obtained were compared statistically with those obtained by the official method and showed no significant differences regarding accuracy and precision.

Use of sodium tetraphenylborate reagent for conductometric titration of Amlodipine Besylate in pure and pharmaceutical forms

Simple, accurate and reliable conductometric method for the quantitative determination of Amlodipine Besylate (AML) in pure form and pharmaceutical formulations using sodium tetraphenylborate (TPB) in aqueous solution at 20°C has been described. The method is based on the formation of ion association complex of cation coming from the cited drug with tetraphenylborate anion and the conductance of the solution is measured as a function of the volume of titrant. Many experimental conditions were evaluated. The described procedure allowed the determination of AML in double distilled water in the range of 0.200-1.000mM. The accuracy of the method is indicated by the excellent recovery 98.60-101.40%, and the precision is supported by the low relative standard deviation < 4.74 %. The method was further applied successively to pharmaceutical formulations with no interference from the excipients, the results obtained were compared statistically with those obtained by the official method and showed no significant differences regarding accuracy and precision.

Estimation of terbinafine HCL by spectophotometric analysis with Tpooo, Nb12br and WFB

One simple and sensitive procedure (simple spectrophotometric method) for the assay of drug Terbinafine HCl in pure form and formulations. This method involves the formation of ion-association complex between TRB and the TPOOO, NB12BR and WFB. In order to establish the optimum conditions necessary for rapid and quantitative formation of coloured product with maximum stability and sensitivity, the author performed experiments by measuring the absorbance at λmax 480nm,420nm and580nm of respective series of solutions, varying one and fixing the other parameters in each case such as type, volume and concentration of acid, organic solvent used for extraction, ratio of organic phase to aqueous phase during extraction, shaking time and temperature. The variable parameters were optimized. The results were statistically validated.

Spectrophotometric Determination of Domperidone Maleate, Carvedilol, Dimetindene Maleate and Cinnarizine in Pharmaceuticals by Ion Association Complex Formation with Erythrosine B Dye

Spectrophotometric Determination of Domperidone Maleate, Carvedilol, Dimetindene Maleate and Cinnarizine in Pharmaceuticals by Ion Association Complex Formation with Erythrosine B Dye

Assessment of two analgesic drugs through fluorescence quenching of acriflavine as a new green methodology

Two non-steroidal anti-inflammatory drugs, ketoprofen and diclofenac sodium could be determined spectrofluorimetrically in their pure forms and different dosage forms using acriflavine reagent. It was found that the quenching of acriflavine fluorescence is going linearly with increasing the concentration over the ranges of 1.0–10.0 μg/mL for both ketoprofen and diclofenac sodium. The proposed method was studied to attain the optimum conditions with maximum sensitivity and precision without harming the environment. A proposal for the reaction mechanism was postulated depending on ion-association complex formation between acriflavine and each of the studied drugs in 1:1 ratio. International council of harmonization (ICH) guidelines were followed to validate the method. The lowest amount that could be detected by the proposed method is 0.28 and 0.48 μg/mL for both ketoprofen and diclofenac sodium, respectively. It was found that no significant difference between the proposed and comparison methods as indicated from the calculated statistical values.

ИСПОЛЬЗОВАНИЕ ХИМИЧЕСКИХ МЕТОДОВ СОБИРАНИЯ И ИССЛЕДОВАНИЯ СЛЕДОВ РУК ПРИ РАССЛЕДОВАНИИ УГОЛОВНЫХ ПРАВОНАРУШЕНИЙ

The article highlights the problems of identification, fixation and study of handprints of varying degrees of latency by chemical methods. The modern technical means used for realization of the specified methods are reviewed. The focus is on the chemicals used to detect latent handprints, namely ninhydrin, alloxan, silver nitrate, cyanoacrylate, lumicyano, curcumin, features of their preparation and application. Recently proposed small particle reagents are considered, which include a suspension of a sparingly soluble substance such as gray molybdenum disulfide MoS2 or for dark surfaces zinc carbonate ZnCO3, detergent, fluorescent or intensely colored dyes. These reagents are suitable for use on various surfaces (metal, paper, plastic, etc.) that are wet or semi-wet, or have been in contact with water for a long time. The mechanism of using the components of such compositions on handprints includes several types of interactions, one of which is the hydrophobic interaction of organic dyes or reagents with the lipid component of handprints, and the second type involves the formation of ion-association complexes between amino groups of amino acids and anionic organic dyes.

Spectrophotometric Determination of Atenolol by Formation of Ion Association Complex

Spectrophotometric Determination of Atenolol by Formation of Ion Association Complex

Indirect Spectrofluorometric Determination of Enoxaparin Sodium in Pharmaceutical Formulation (Injection) by Ion Association Complex Formation with Acriflavine Dye

A simple, sensitive and selective spectrofluorometric method has been developed for the determination of enoxaparin sodium in bulk and dosage forms (injection). The method was based on the quantitative quenching effect of enoxaparin on the native fluorescence of acriflavine due to the formation of nonfluorescent supramolecular ion issociation complex between the studied drug and acriflavine dye in aqueous solution. The decrease of acriflavine fluorescence was observed at 506 nm after excitation at 402 nm. The relationship between quenching fluorescence intensity and concentration of enoxaparin sodium was linear in the range 0.05-20 µg/ml and with correlation coefficient 0.9990 and with LOD and LOQ 0.011 and 0.035 µg/ml respectively. The average recovery was 100.51% and RSD is less than 3.23%. The stoichiometry of enoxaparin to acriflavine was calculated a 1:4. The method was applied successfully to the determination of enoxaparin form injection samples and the results were in a good agreement with certified value and standard addition procedure.

ЕКСПРЕСНЕ, ВИСОКОЧУТЛИВЕ ТА СЕЛЕКТИВНЕ СПЕКТРОФОТОМЕТРИЧНЕ ВИЗНАЧЕННЯ КАДМІЮ(II) З ВИКОРИСТАННЯМ ІОННОГО АСОЦІАТУ ТЕТРАЙОДОКАДМІАТУ(II) З АСТРАФЛОКСИНОМ

A very simple, rapid, highly sensitive and selective non-extractive spectrophotometric method for the determination of trace amounts of cadmium(II) has been proposed. It is based on the formation of ion association complex (IA) between iodide complex of cadmium Cd(II) [CdJ42-] and polymethine dye Astra Phloxine FF. The color of the solution changes from red to red-purple. The color of the IA develops completely at temperature less than 18 oC after 5-10 minutes after mixing of reagents and remains constant over several hours. Opitmal concentrations of HCl, AP and KJ are 0.07–0.13 M, 1.2×10-5 M and 6×10-3 M, respectively. The molar absorptivity of the IA is 6.5×104 mol-1 L cm-1. The calibration graph is linear between 1×10-7 and 3×10-6 mol L-1 of cadmium (II). The limit of detection is 5×10-8 mol L-1 (l = 5 cm, 0.006 mg L-1). A large excess of over 50 cations, anions and some common complexing agents do not interfere with the determination. The method was successfully applied in the determination of cadmium in Wood`s alloy and mine water.

Spectrophptometric Analysis of Clathromycin with Tpooo, Ars and WFB

One simple and sensitive procedure (simple spectrophotometric method) for the assay of drug clarithromycin in pure form and formulations. This method involves the formation of ion-association complex between CAM and the TPOOO, ARS and WFB. In order to establish the optimum conditions necessary for rapid and quantitative formation of coloured product with maximum stability and sensitivity, the author performed experiments by measuring the absorbance at λmax 480nm,420nm and580nm of respective series of solutions, varying one and fixing the other parameters in each case such as type, volume and concentration of acid, organic solvent used for extraction, ratio of organic phase to aqueous phase during extraction, shaking time and temperature. The variable parameters were optimized. The results were statistically validated.

Analytical method for the assay of Perindopril Erbumine in formulations by ion association complex formation using Tropaeolin OOO (TPOOO)

Analytical method for the assay of Perindopril Erbumine in formulations by ion association complex formation using Tropaeolin OOO (TPOOO)

New Conductometric Titration Methods for Determination of Diphenhydramine Hydrochloride Using Sodium Tetraphenylborate and Cetylpyridinium Bromide

Sodium tetraphenylborate (TPB) and cetylpyridinium bromide (CPB) were used as titrant for the conductometric determination of diphenhydramine hydrochloride (DPH) drug through ion association complex formation and then the conductance of the solution is measured as a function of the volume of titrant. The effect of the solvent, reagent concentration, temperature and molar combining ratio of the formed ion-associates were studied and evaluated. The suggested method was applied for the determination of diphenhydramine hydrochloride in pure form and pharmaceutical preparations. The described procedures allowed the determination of the studied drug in bi-distilled water in the range of 0.75–16 mg. Statistical treatment of the experimental results indicates that the method is precise and accurate. The accuracy of the method was indicated by excellent recovery and the precision supported by the low relative standard deviation <1%. The sensitivity of the proposed method was discussed and the results were compared with the potentiometric pharmacopoeial method. The proposed procedure was simple, precise and low cost and can be applied for the routine measurements of the cited drug.

UV Spectrophotometric Analysis of Drugs Terbinafine Hydrochloride and Clarithromycin

One simple and sensitive procedure (UV spectophotometric method) for the assay of two drugs namely terbinafine hydrochloride and clarithromycin in pure form and formulations. This method involves the formation of ion-association complex between TRB or CAM and the picric acid. In order to establish the optimum conditions necessary for rapid and quantitative formation of coloured product with maximum stability and sensitivity, the author performed experiments by measuring the absorbance at λmax 350 nm of a series of solutions, varying one and fixing the other parameters in each case such as type, volume and concentration of acid, organic solvent used for extraction, ratio of organic phase to aqueous phase during extraction, shaking time and temperature. The variable parameters were optimized. The results were statistically validated.

Superior adsorption performance for triphenylmethane dyes on 3D architectures assembled by ZnO nanosheets as thin as ∼1.5 nm

The 3-dimensional hierarchical ZnO flower-like architectures have been synthesized in a Zn(Ac)2·2H2O-Na2SeO3-KBH4-pyridine solvothermal system at 100°C for 24h. The flower-like architecture is assembled from ZnO nanosheets with a thickness of ∼1.5nm, and the flower-like architecture specific surface area is 132m2/g. When the ZnO flower-like architecture is used as the adsorbent for acid fuschin (AF), malachite green (MG), basic fuchsin (BF), congo red (CR) and acid red (AR) in water, the adsorption capacities for AF, MG, BF, CR and AR are 7154.9, 2587.0, 1377.9, 85.0 and 38.0mg/g, respectively. Evidently, the as-obtained ZnO flower-like architectures show excellent adsorption performances for triphenylmethane dyes, and the adsorption capacity of 7154.9mg/g for AF is the highest of all adsorbents for dyes. The adsorption mechanism can be attributed to the electrostatic attraction and the formation of ion-association complex between triphenylmethane dyes and ZnO hierarchical flower-like architectures.

NEW SPECTROPHOTOMETRY METHOD FOR THE DETERMINATION OF MIRTAZAPINE IN PHARMACEUTICAL FORMULATIONS

A simple extractive spectrophotometric method has been developed for the quantification of mirtazapine. This method is based on the formation of ion-association complex of mirtazapine drug with bromocresol purple dye. The absorbance of the complex was measured at 400 nm. The method was successfully applied to the determination of mirtazapine in their pharmaceutical formulations. The method shows a linear range from 0.2-10 μg mL -1 with a molar absorptivity of 1.53 ‘10 4 L mol -1 cm -1 . The limit of detection (LOD) and limit of quantification (LOQ) were found to be 0.096 μg mL -1 and 0.32μg mL -1 respectively. The developed methodology was successfully applied for the determination of mirtazapine in commercial formulation and the percentage recovery was found 99.91 ± 0.15. The developed methodology promises a feasible, low cost and an efficient method for the routine analysis.

A New Extractive Spectrophotometric Method for the Estimation of Alosetron

Two simple, accurate, rapid and sensitive Methods (A and B) have been developed for the estimation of Alosetron in its pharmaceutical dosage form. The Method A is based on the formation yellow colored chromogen, due to reaction of Alosetron Hydrochloride with Metanil yellow dye, formation of ion association complexes of the drug with dyes in phosphate buffer of pH 3.6 followed by their extraction in chloroform which exhibits λmax at 410 nm. The Method B is based on the formation of light yellow colored chromogen due to reaction of Alosetron Hydrochloride with Methyl Orange dye, formation of ion association complexes of the drug with dyes in phosphate buffer of pH 3.6 followed by their extraction in chloroform, which exhibits λ max at 422 nm. The absorbance-concentration plot is linear over the range of 5-60 mcg/mL for Method A and 50-120 mcg/mL for Method B. Results of analysis for all the methods were validated statistically and by recovery studies. The proposed methods are precise, accurate, economical and sensitive for the estimation of Alosetron in bulk drug and in its Tablet dosage form.

English

A simple, precise and low cost conductometric method for the determination of alfuzosin hydrochloride and fexofenadine hydrochloride in pure form and pharmaceutical formulations using sodium tetraphenylborate has been described. The method is based on the formation of ion association complex of cations coming from the cited drugs with tetraphenylborate anions and the conductance of the solution is measured as a function of the volume of titrant. Various experimental conditions were evaluated. The described procedures allowed the determination of the studied drugs in double distilled water in the range of 2.13 - 10.65 and 2.50 - 13.45 mg of alfuzosin hydrochloride and fexofenadine hydrochloride, respectively. Statistical treatment of the experimental results indicates that the method is precise and accurate. The accuracy of the method is indicated by the excellent recovery 99.85-102.49 and 99.80-100.48% for alfuzosin hydrochloride and fexofenadine hydrochloride, respectively, and the precision is supported by the low relative standard deviation < 3.04%. The method was further applied successively to pharmaceutical formulations, the proposed method offering a high degree of accuracy and precision when compared to potentiometric pharmacopoeial methods.

Extractive Visible Spectrophotometric Determination of Lamotrigine in Pure and Pharmaceutical Formulations

Two simple, sensitive, accurate and economical spectrophotometric methods (A & B) for the determination of lamotrigine (LMT) in pure and pharmaceutical formulations (tablets) are described in the present work. Method A is based on the formation of coloured ion-association complex between lamotrigine and tropaeolineo-oo (TPooo) with absorption maximum at 485 nm and obeys Beer's law in the concentration range of 5-25 µg/mL. Formation of ion-association complex between lamotrigine and alizarine Red S (ARS) to yield a coloured chromogen exhibiting absorption maximum at 440 nm (Method B) obeying Beer's law in the concentration range of 5-25 µg/mL forms the basis of Method B. The two methods have been validated statistically through recovery studies. The results are compared with those obtained using UV spectrophotometric method (Reference method) in chloroform at 260 nm.

A rapid spectrophotometric method for measuring arsenic in water after enrichment of arsenomolybdate on polyurethane foam and complexation with Rhodamine B

Simple, rapid and accurate spectrophotometric method is presented for the determination of arsenic in water. The method is based on the preconcentration of arsenomolybdate on polyurethane foam followed by its elution in acetone and formation of ion association complex of arsenomolybdate with Rhodamine B. The absorbance of the complex is measured at 560 inn. The colour system obeys Beer's law from 0.5-5.0 ng mL(-1) of arsenic. The detection limit has been found to be 0.10 ng mL(-1) of As. The molar absorptivity was found to be 2.25 x 10(6) L mol(-1) cm(-1). Under optimized conditions, the proposed method was applied to the determination of arsenic present in surface and ground water samples collected from lakes and tube wells. The method has been applied successfully to determine arsenic in NIST standard water sample and the result is in good agreement with the certified value.