Sensitive Spectrophotometric Method For Determination Research Articles

Spectrophotometric determination of Methyldopa in pure form and in the pharmaceutical preparations

A simple, rapid and sensitive spectrophotometric method for determination of methyldopa (MD) using 4-chloro-7-nitrobenzo-2-oxa-1, 3-diazole (NBD-Cl) as reagent in an alkaline medium (pH 12.3). Absorbance of the resulting brown-colored product is measured at 470 nm. Beer’s Law is obeyed in a concentration range of (1.6-17.6 µg/mL) with molar absorptivity (1.9337×104 L/mol.cm), correlation coefficient 0.9988, and the limit of detection (5.536×10-3 µg/mL). The method has been successfully applied to the determination of Methyldopa in pharmaceutical preparations.

Spectrophotometric Determination of Lisinopril Drug by Oxidative Coupling Reaction with 4-aminonaphthalene-1- sulfonic acid Reagent

A simple, rapid and sensitive spectrophotometric method for determination of Lisinopril (LS) in both pure form and pharmaceutical preparations has been reported. The adapted technique based on utilization 4-aminonaphthalene-1-sulfonic acid as a Chromogenic reagent through an oxidative coupling reaction with Lisinopril and Potassium Peroxydisulfate (oxidation agent) in acidic medium to form green dye soluble product absorption maxima at 612 nm. Linearity was in the range 2–43 μg ml-1. The values of molar absorption coefficient (ε), correlation coefficient and Sandel’s index were found to be 10.3808 × 103 L. mole-1 cm-1, 0.9995 and 0.00343 µg.cm-2 respectively. The average of recovery % was 100.067. Detection Limit and quantitative limit were 0.0343 µg/ml and 0.1143 µg/ml. The proposed method has been successfully applied in the determination of preparations containing lisinopril.

Indirect Spectrophotometric Determination of Mebendazole Using Methyl Orange Dyein the Presence of the Oxidizing Agent NBS

Aim: To develop a swift , simple, accurate and sensitive spectrophotometric method for determination of mebendazole (MBZL) in pure and pharmaceutical formulations. Methods: The suggested method depend on oxidation of MBZL with known excess amount of N-bromosuccinimide ( NBS ) in acidic medium and after reaction is insured to be complete , the surplus NBS is estimated by de colorization of methyl orange (MO) dye and measuring the absorbance of surplus dye at 508 nm. A linear calibration curve was obtained over the concentration range 2.5– 25 μg.ml-1 with correlation coefficient of 0.9997. The molar absorptivity and sandell's sensitivity index values were determined to be 1.505 × 104 L.mol-1.cm-1 and 0.019607 μg.cm-2. The limit of detection (LOD) and quantification (LOQ) were calculated to be 0.3736 and 2.553 μg.ml-1, respectively. The proposed method has been successfully applied to the determination of MBZL in available dosage form, the validity proposed method was confirmed by recovery study via standard addition technique . Keywords: mebendazole ; N-bromosuccinimide ; Determination ;Spectrophotometry ; methyl orange

Spectrophotometric Methods for Determination of Dopamine Hydrochloride in Bulk and in Injectable Forms

Two highly simple, economical, accurate and sensitive spectrophotometric methods for determination of dopamine hydrochloride (DAH) in either pure form and pharmaceutical formulations are described. The first method is based on determination of (DAH) spectrophotometrically at maximum absorbance 280 nm (method A). The second one is based on reduction of alkaline KMnO4 by (DAH) leading to the formation of green manganate species which are measured at 610 nm (method B). Under optimized conditions, the calibration graphs were linear in the range of 3.793 – 45.513, 0.190 – 4.362 μg.mL−1 of (DAH) for methods A and B respectively. The developed methods were successfully applied for the determination of dopamine hydrochloride in pharmaceutical samples.

SPECTROPHOTOMETRIC ESTIMATION OF TOTAL ALKALOIDS IN CHITRAKA (PLUMBAGO ZEYLANICA LINN) USING BROMOCRESOL GREEN

Background: Plumbago zeylanica L. (Plumbaginaceae) commonly known, as Chitraka is pharmacologically important plant. Various studies have been undertaken to assess the pharmacological potential of different parts of the plant namely like roots, stem, flower, and leaves as antimicrobial, hepatoprotective, anticancer, antifertility, antiulcer, antifungal and wound healing. Chitraka is rich in alkaloids hence present study is taken. Objective: The objective of the present study was to determine the total alkaloid content in Chitraka Materials & Methods: The presence of alkaloids was confirmed by qualitative dragendroffs method subjected to quantification, the total alkaloid content (TAC) was estimated spectrophotometric ally using Bromocresol green method with Atropine as standard. Results: The results showed that root of Chitraka are rich source of alkaloids. The root extract of chitraka showed highest alkaloid content 83.4mg/g Atropine equivalent. Conclusion: The total alkaloid content of Chitraka was well established by spectrophotometric studies. And it is direct, simple & sensitive spectrophotometric method for determination of total alkaloid based on the reaction with Bromocresol green

Indirect Spectrophotometric Estimation of Ciprofloxacin Hydrochloride in Pharmaceuticals using N-Bromosuccinimide and Methylene Blue Dye

The present study aims to develop a swift , simple, accurate and sensitive spectrophotometric method for determination of Ciprofloxacin Hydrochloride ( CPFX ) in pure and pharmaceutical formulations. The suggested method depend on oxidation of CPFX with known excess amount of N-bromosuccinimide ( NBS ) in acidic medium and after reaction is insured to be complete , the surplus NBS is estimated by de colorization of methylene blue dye and measuring the absorbance of surplus dye at 665 nm . A linear calibration curve was obtained over the concentration range 0.5 – 4.5 μg.ml-1 with correlation coefficient of 0.9993 . The molar absorptivity and sandell's sensitivity index values were determined to be 8.6 ×104 L.mol-1.cm-1 and 0.004276 µg.cm-2, respectively .The limit of detection (LOD) and quantification (LOQ) were calculated to be 0.0033 and 0.0111 μg.ml-1, respectively . The proposed method has been successfully applied to the determination of CIPH in available dosage form, the validity proposed method was confirmed by recovery study via standard addition technique .

Spectroscopic Estimation of Cefepime by using Batch, Cloud Point extraction and Flow Injection Analysis methods

The purpose of the study new simple, quick and sensitive spectrophotometric methods for determination of cefepime (CFM) in pure and Pharmaceutical Formulations. The primary amine was converted to an azo-dye coupling in the alkaline medium by 2,6 -dimethylphenol for stable reddish-orange color at a wave length of 515 nm. The concentration ranges 2-50 μg / mL, Beer's law is obeyed, the correlation coefficient, molar absorptivity , detection limit were 0.9996,0.826×104and 0.192 respectively .To estimation the trace concentration of dye used cloud point extraction (CPE) technique , followed by UV-Vis spectrophotometer .Detailed analysis and a series of ideal conditions were carried out on the influence of several parameters, such as surfactant form and volume, salt, temperature and incubation times on the cefepime CPE. The concentration range obeyed the Beer's law was 0.25-10 μg / mL, correlation coefficient was 0.9997, molar absorptivity was 1.169×105 L.mol-1.cm-1, detection limit was 0.027 μg/mL, Pre-concentration factor was 25 and Distribution coefficient(D) was 332.35. A flow injection analysis it’s simple technique for determination the cefepime. The concentration ranges 1-150 μg / mL, Beer's law is obeyed, correlation coefficient was 0.9997, molar absorptivity was 0.341×104L.mol-1.cm-1 and the detection limit was 0.464 μg/mL. For the determination of cefepime in pharmaceutical formulation the methods suggested were successfully used.

Silver Nanoparticles Synthesis for Sensitive Spectrophotometric Determination of Sofosbuvir, Lamivudine, and Ritonavir in Pure Forms and Pharmaceutical Dosage Forms.

Silver nanoparticles synthesis is now widely applicable as a method for sensitive spectrophotometric determination of many pharmaceuticals. A highly sensitive, cheap, green, nonextractive, and accurate spectrophotometric method was developed for the determination of three important antiviral drugs. The method depends on the formation of silver nanoparticles as a result of the redox reaction between antiviral drugs as a reducing agent and AgNO3 as an oxidizing agent in presence of polyvinyl pyrrolidone as a stabilizing agent. The UV absorbance of the resulted golden yellow silver nanoparticles can be easily measured at 421 nm for Sofosbuvir (SFS) and Ritonavir (RIT) and at 425 nm for Lamivudine (LAM). The LODs were 23.5, 30, and 21.5 nm/mL for SFS, LAM, and RIT, respectively. The LOQs were 70.5, 90, and 64.6 nm/mL for SFS, LAM, and RIT, respectively. The method was validated according to International Conference on Harmonization guidelines, and it was successively applied for the determination of the studied drugs in their different pharmaceutical dosage forms and gave excellent percent of recovery. The results showed excellent agreement with the reported method with respect to precision and accuracy. Being simple, fast, robust, and economic, this method is eligible for use in the routine work in pharmaceutical quality control laboratories. A sensitive and economic spectrophotometric method was developed and validated for quantitative determination of SFS, LAM, and RIT. The method was validated and applied for determination of the studied drugs in their different formulations. The method used water as the main solvent, so our proposed method is considered environmentally friendly.

A new sensitive spectrophotometric method for determination of saliva and blood glucose.

There is an increasing need for accurate and inexpensive glucometers as the world moves toward personalized medicine. Among the existing technologies, photometric based devices are more desired due to the cost-effectiveness, ease-of-use and the potential to be adopted in the smart-phone technology for remote sensing and self-monitoring purposes. However, the accuracy, precision, and reproducibility of the results of these devices are heavily dependent on the details of the chosen glucose measuring method. Considering the delicate problems with the current spectrophotometric methods, a new method was developed for more precise, accurate, and fast measurement of blood glucose via the coupled reactions of glucose oxidase and peroxidase using 4-[(4-Hydroxy-3-methoxyphenyl) azo]-benzenesulfonic acid (GASA) as the substrate. Stability of GASA and its oxidized products along with its direct and fast consumption by peroxidase, made it possible to determine blood glucose concentration in <20s with high reproducibility. The low detection limit of GASA method (0.36mg dL-1) with a linear range from 0.36 to 399.6mg.dL-1 also allowed determination of salivary glucose concentration (SGC). As compared with the blood samples, the SGC results were more dispersed, especially for the diabetic participants, assumingly due to the diverse nature of salivary samples. However, a good correlation coefficient of 0.81 for non-diabetic individuals showed that it is accurate enough to recognize non-diabetic from diabetic condition. Results of this study disclose the potential application of GASA method as a reliable alternative for the current spectrophotometric methods with the ability to be adopted in miniaturized glucometers.

Spectrophotometric Determination of sulphadiazine by oxidative coupling reaction with ortho-amino phenol as reagent

A simple, rapid and sensitive spectrophotometric method for determination of sulphadiazine (SDZ) in aqueous solution is described. The method iis based on the oxidation of SDZ by potasium Periodate, and coupling with ortho-amino phenol to give a violet colour of maximum absorbaance at 532 nm. Beer's law is obeyed over the concentration range of 5-40 µg /ml of SDZ with a (R2=0.9980) and molar absorptivity 5581.6 L.mol-1.cm-1 and a relative error in the range of - 0.06 - 2.3 % and a relative standard deviation of not more than 0.31 %. The composition of the resulting product is also investigated and it is found to be1:1. The method is successfully applied for the determinatiion of SDZ in pure and pharmaceutical dosage forms, with recovery of noot less than 101.1%.

A Creative Indirect Spectrophotometric Determination of Naproxen

A New, sensitive spectrophotometric method for determination of Naproxen (Nap) has been proposed. The method is based on a modification of Naproxen into a hydroxy analog (mNap). The modified compound is coupled with the diazotized p-aminobenzoic acid (PABA) in alkaline medium, the resulting orange azo dye exhibit a maximum absorption at 500 nm. Beer's law is obeyed over the concentration range from 10 to 650 µg/20 ml, (i.e. 0.5-32.5 µg/ ml) with a good sensitivity (molar absorptivity 2.14x104 l.mol-1.cm-1), good precision (RSD% better than ±1.93%) and high accuracy (relative error % better than 0.43%), Sandell's sensitivity index is 0.0107µg.cm-2 and the limit of detection (LOD) is 0.024 µg/ml and the limit of quantitation (LOQ) is 0.082 µg/ml. The method has been applied successfully for determination of Naproxen in dosage forms after extraction of the active ingredient. .

Spectrophotometric method for determination of Glucosamine Sulphate in dosage forms by derivatization using Quality by Design approach

A Quality by Design approach was used to develop a sensitive spectrophotometric method for determination of glucosamine Sulphate in pharmaceutical dosage forms and optimize a derivatization reaction of glucosamine with o-phthalaldhyde. This strategy was focused on derivatization process understanding and analytical method development and validation. Both of them were evaluated by applying risk assessment and Design Space tools. The scouting step was carried out by analyzing different derivatizing agents, type of buffers, pH of buffers, and time of reaction. Five critical process parameters (CPPs) were selected related to, pH of borate buffer, volume of 2-mercaptoethanol (ME), volume of o-phthalaldhyde (OPA), and the time of reaction. The effect of different levels of CPPs on critical quality attributes (CQAs) (the absorbance of derivative) was evaluated in the screening design using fractional factorial design. Using response surface methodology and contour plots the optimum values of the selected factors were determined and the design space of the method was defined. Finally, control strategy was designed and the method was validated and applied to a real sample of glucosamine dosage forms using the optimum derivatization conditions of the reaction; pH of borate buffer 10.5, concentration of buffer 0.05M, Time of reaction 10.7 minutes, volume of ME 100μL, and volume of OPA 5.1mL at room temperature. The results of the present study clearly shown that the developed method was sensitive relative to the other published spectrophotometric and HPLC methods with identification of the most significant factors affecting the derivatization reaction.

Indirect Spectrophotometric Method for Determination of Bromhexine-HCl in Pharmaceutical Preparations

A simple, accurate and sensitive spectrophotometric method for determination of bromhexine-HCl in aqueous solution has been described. The proposed method is based on the reduction of cerium (Іν) in acidic medium into cerium (Ш) by the drug followed by the complex formation of cerium (Ш) with arsenazo Ш to form a greenish-blue water soluble, stable complex that has a maximum absorbance at 651nm against the reagent blank. Beer’s law is obeyed in the range of 10 to 200μg of bromhexine-HCl /20 ml (i.e. 0.5-10 ppm) with molar absorptivity of 1.48×104 l.mol-1. cm-1 and a good determination coefficient (R2=0.9978). The limit of detection (LOD) and limit of quantification (LOQ) are 0.408 and 1.394μg ml−1, respectively. The relative error and a relative standard deviations are found in the range -0.354 to1.93 % and ± 0.135 to ± 1.033%, respectively, depending on the conc-entration level. The method is suitable for the determination of bromhexine-HCl in the presence of other ingredients that are usually present in dosage forms. This procedure is applied successfully for the analysis of bromhexine-HCl in pharmaceutical preparations (tablets, syrup and injection) without prior separation and with acceptable errors

A sensitive method for the determination of Sulfonamides in seawater samples by Solid Phase Extraction and UV–Visible spectrophotometry

The authors have developed a sensitive spectrophotometric method for determination of sulfonamide derivatives such as sulfanilamide (SAA), sulfadiazine (SDZ), sulfacetamide (SCT) sulfamethoxazole (SMX), sulfamerazine (SMR), sulfadimethoxine (SDX), sulfamethiazole (SMT) and Sulfathiazole (STZ). This method is based on the Bratton-Marshall reaction, which involves the diazotization of sulfonamides with sodium nitrite under acidic conditions, followed by coupling with N-(1-naphtyl) ethylenediamine dihydrochloride (NED) to form a pink colored compound. Therefore, the Bratton-Marshall method was modified by optimizing the reaction conditions, which allows us to determine a low concentration range of sulfonamides compared to the reported methods. The limits of detection and quantification obtained were 0.019–0.05 and 0.06–0.16μgmL−1, respectively. In comparison with other reported methods using different coupling agents, the proposed method was found to be the most simple and sensitive for sulfonamides determination. In this paper, the modified method was successfully employed for the determination of sulfonamides in drinking water, seawater and pharmaceutical and veterinary formulations.The purpose of this work is to optimize and develop a simple method for extraction and concentration of sulfonamides present as residues in seawater and their quantification with the recommended spectrophotometric method. Solid phase extraction (SPE) of sulfonamides from seawater samples was evaluated using Oasis HLB cartridges (3mL, 540mg). The recovery efficiency was investigated in the sulfonamides concentration range comprised between 0.19 and 126ngmL−1. The ease of use of this extraction method makes it very useful for routine laboratory work.

Validation of sensitive spectrophotometric method for determination of Salmeterol xinafoate and Fenoterol hydrobromide via o-Phenanthroline and iron complexation

Block Copolymer Self-assembled and Cross-linked Nanoassemblies for Combination Delivery of Iron Oxide and DoxorubicinDaniel Scott, Yihwa Beabout , Robert J. Wydra, Mo Dan, Robert Yokel, J. Zach Hilt and Younsoo Bae

Application of Spectrophotometric Methods for the Determination of Thiamine (VB1) in Pharmaceutical Formulations Using 7-Chloro-4-Nitrobenzoxadiazole (NBD-Cl)

Simple, swift and sensitive method for Spectrophotometric determination of thiamine (VB1) in pharmaceutical tablets has been described. The proposed method is based on the reaction of thiamine (VB1) and 7-Chloro-4-nitrobenzoxadiazole (NBD-Cl) at alkaline medium (pH 10.5) to develop a deep brown adduct that bears maximum absorption at 434 nm. Beer’s law is obeyed in the concentration range 5-35 µg/ml of thiamine at the selected wavelength. Under optimized reaction conditions, the linear regression coefficients were a=0.033, b=-0.009, and r2=0.999 calculated for the general equation of the calibration curve (y = ax + b). The limit of detection (LOD) and limit of quantification (LOQ) were found to be 0.667µg/ml and 2.020µg/ml respectively. The method has been successfully applied to the determination of thiamine (VB1) in pharmaceutical formulations, and can be used as an alternative of the existing sophisticated method used in drug laboratories and factories.

Development of a Novel Spectrophotometric Method Based on Diazotization- Coupling Reaction for Determination of Bisphenol A

Bisphenol A (BPA) is an industrial material which can lead to endocrine disorders. In this work, a simple and sensitive spectrophotometric method for determination of BPA using diazotization-coupling reaction was presented. To achieve the best performance of the developed method, the experimental parameters were optimized in terms of reagent concentration, reaction time, pH, and temperature. Under the optimal conditions, the absorbance increased linearly with the increasing concentration of BPA in the range of 0.16-10.4 µg mL-1 with the correlation coefficient of 0.9991 and the detection limit of 0.05 µg mL-1. Results achieved with the spectrophotometric method were compared with those obtained using high performance liquid chromatography (HPLC) method. The proposed method was successfully applied to determine BPA in milk and water bottle samples and satisfactory results were obtained, which make it very suitable for routine analysis of BPA in quality control laboratories.

Spectrophotometric determination of Cobalt II with PAN using Flow injection technique.

A simple, rapid, reproducible and sensitive spectrophotometric method fordetermination of Cobalt (Co2+) was investigated .The method was based on theinteraction of Co2+ with 1-(2-pyridylazo)2-naphthol (PAN), in the presence ofbuffer pH 6 (CH3COOH + CH3COONH4) to give a highly colored species of amolar ratio 1:2 (Co:PAN) .Beers law was obeyed in the range of (0.1-2.5)μg/ml with the molar absorptivity of 3.77x104 L.mol-.cm- at λ max 525 nm.The method was adapted to semi automated flow injection system .The molarabsorptivity was 0.16x104 L.mol-.cm- at λ max 525 nm .Beers law was obeyedin the range (0.3-10) μg/ml. The precision and accuracy studied to bothsystems. The method was applied successfully to the assay of Co2+ in realsample such as real water and waste water, and was well agreed with itscertified value.

Determination of Dicofol in Various Environmental Samples by Spectrophotometric Method Using Chromogenic Reagent

A sensitive spectrophotometric method for determination of dicofol in subparts per million levels is described, which is based on Fujiwara reaction. Dicofol on alkaline hydrolysis gives chloroform, which reacts with pyridine to produce red color. The color is discharged by addition of glacial acetic acid. The glutaconic aldehyde formed reacts with 4-aminoacetanilide to gave an orange-red dye which is extractable in 3-methyl-1-butanol. The extracted dye shows absorption maximum at 525 nm. Beer's law is obeyed in the range of 0.025–0.25 μg mL−1. Important analytical parameters such as time, temperature, reagent concentration, acidity etc. have been optimized for complete color reaction. Sandell's sensitivity and molar absorptivity for the system were found to be 0.000343 μg cm−2 and 1.077 × 106 L mol−1cm−1, respectively. The proposed method is satisfactorily applied to microlevel determination of dicofol in various environmental samples.

Indirect micellar spectrophotometric determination of lead in various soybean based products using green chemistry

The study was conducted for the purpose of quantifying lead in various samples of soy-products by micellar spectrophotometry using green chemistry approach. The ligandN2P4HB was synthesized for the purpose with the help of weak acid and is found to be soluble in alcohol, acetone and in chlorinated hydrocarbons such as chloroform. It dissolves in alkaline aqueous media but is practically insoluble in water at pH less than 6. In the presence of surfactants its solubility has been found to be increased significantly. On addition of solution of ligand in presence of surfactants to metal ion solution, colored complex were formed. The local nonpolar microenvironment of the micelles incorporates the non-polar colored complex. Secondly a marked increase in absorption intensity has also been observed. This phenomenon of micellar solubilization with increasing absorption intensity has been used to develop a novel, green, simple, inexpensive and sensitive spectrophotometric method for determination of heavy metal ion in various soy products.