Sensitive Spectrophotometric Method Research Articles

Spectrophotometric determination of metoclopramide hydrochloride in pharmaceutical tablets, by diazotization-coupling method with 1-naphthol as the coupling agent

Simple, rapid and sensitive spectrophotometric method was proposed for the analysis of metoclopramide hydrochloride (MPH) in pure form as well as in pharmaceutical tablets. The method is based on the diazotization reaction of MPH with sodium nitrite in hydrochloric acid medium to form diazonium salt, which is coupled with 1-naphthol in sodium hydroxide medium to form azo dye, showing absorption maxima at 550 nm. Beer’s law is obeyed in the concentration range of 0.4 – 18 µg mL-1 of MPH with detection limit 0.5448 µg mL-1. The molar absorptivity and Sandell’s sensitivity are 3.4969 × 104 L mol-1 cm-1 and 0.0101 µg cm-2, respectively. The method was successfully applied to the determination of MPH in pharmaceutical tablets without any interference from common excipients used as additives in tablets. The results agree favorably with the official British Pharmacopoeia method.

Safety method, Spectrophotometric Determination of Sulfamethaxazole drug in bulk and Pharmaceutical Preparations

A simple, cheap, fast, accurate, Safety and sensitive spectrophotometric method for the determination of sulfamethaxazole (SFMx), in pure form and pharmaceutical dosage forms. has been described The Method is based on the diazotization of the drug by sodium nitrite in acidic medium at 5Cº followed by coupling with salbutamol sulphate (SBS) drug to form orange color the product was stabilized and measured at 452 nm Beer’s law is obeyed in the concentration range of 2.5-87.5 ?g ml-1 with molar absorptivity of 2.5x104 L mole-1 cm-1. All variables including the reagent concentration, reaction time, color stability period, and sulfamethaxazole /salbutamol ratio were studied in order to optimize the reaction conditions. No interferences were observed Results of analysis were validated statistically and by recovery studies. These methods are successfully employed for the determination of sulfamethaxazole in some pharmaceutical preparations.. The developed method is easy to use and accurate for routine studies relative to HPLC and other techniques.

Spectrophotometric determination of mercaptopurine and dimercaprol for use in physiological and environmental application

Mercaptopurine (MP) and dimercaprol (DMC) are mercaptons which are used to treat cancer and acute poisoning like arsenic, mercury, gold and lead respectively. The quality and quantity of these drugs in the marketed pharmaceutical formulations need to be ensured to reduce toxicity and to achieve a better therapeutic effect. The excessive exploitation of these drugs may exert harmful effects on human health. On the other hand, expiry date chemicals after thrown in water bodies are dangerous for environment. The quick determination of these drugs in pharmaceutical formulations, biological fluids and water samples is of great importance. Hence, simple and sensitive spectrophotometric method was developed for their determination. The reactions of compounds with carbon disulphide and copper(I) perchlorate were carried out in the presence of sodiumbicarbonate to form a yellow coloured copper(I) drug dithiocarbamate complex and it was investigated for the spectrophotometric determination of these drugs. The analysis was accomplished by measuring the intensity of yellow colour at 370 and 455nm respectively for mercaptopurine and DMC against a reagent blank. Under the optimized conditions, calibration graphs were linear in the ranges of 3.04-60.86 and 1.24-18.63 μg/mL with the detection limit (3.3 σ / s) of 0.7480 and 0.3227 μg/mL respectively. The high recoveries of the mercaptopurine and dimercaaprol drugs by the proposed method from respective pharmaceutical formulations (98.0-99.8 and 98.3-99.6), simulated biological fluids (87.0-95.2 and 87.5-94.5 %) and spiked water samples (88.3-95.5 and 87.5-95.1 %) indicate good accuracy and precision of the method.

Xác định acetamiprid bằng phương pháp quang học sử dụng dung dịch nano vàng được ổn định bằng Polydiallyldimethylammoni clorua

On this research, the development of a simple, cost-efective and highly sensitive spectrophotometric method for acetamiprid detection based on the localized surface plasmon resonance of polydiallyldimethylammonium chloridestabilized gold nanoparticles. By naked eyes, one can detect acetamiprid by the visual change of gold solution color from red to purple, corresponding to the shift of maximum absorbance wavelength in the UV-Vis spectrum. Quantification of acetamiprid is possible through a linear relationship between the maximum absorbance wavelength and the acetamiprid concentrations in the range of 8×10-8 -2×10-6 M. Under the optimum conditions including pH 5, NaCl concentration of 0.02 M and incubation time 20 min, the present method has high precision (RSD < 5%), very low limit of detection (LOD) of 2.7×10-8 M, limit of quantification (LOQ) of 8.2×10-8 M. This method has been successfully applied to determine acetamiprid in several pesticide samples and vegetable samples. The measurement results of acetamiprid in the pesticide samples of the research method with the HPLC-UV method showed a difference of < 2%, while for the vegetable sample, the difference between the research method and the LC-MS/method method/ MS < 5% shows that the method has high accuracy and reliability.

Spectrophotometric Study of Excitatory Amino Acids with Ortho-Phthalaldehyde

Background: Understanding the concentration of amino acids in biological samples is pivotal for numerous biochemical and clinical studies. Aspartic acid and glutamic acid, being excitatory amino acids, play crucial roles in the neurotransmission processes of the mammalian brain. Their precise quantification is essential for advancing our knowledge in neurochemistry and for the diagnosis of related disorders. Objective: This study aimed to develop a robust, accurate, and sensitive spectrophotometric method for quantifying aspartic and glutamic acids in solution, both in their native forms and when complexed with ortho-phthalaldehyde (OPA), a derivatization agent that enhances their absorbance properties. Methods: Utilizing a double-beam Hitachi 220 Spectrophotometer equipped with dual 1 cm silica cuvettes, we performed spectrophotometric analyses across a wavelength range of 165 to 1000 nm. Calibration curves for aspartic acid and glutamic acid, with and without OPA, were generated by plotting absorbance against concentration. Various solvents including methanol, ethanol, acetone, and acetonitrile were evaluated for their efficacy in dissolving the amino acids and their complexes. Linear regression analysis was employed to establish the relationship between concentration and absorbance, and the method's precision and accuracy were validated through replicate measurements at multiple concentrations. Results: The calibration curves exhibited excellent linearity for both amino acids, with and without OPA, across the tested concentration ranges. For aspartic acid, absorption maxima were observed at 201 nm (106,333.33 L mol^-1 cm^-1 molar absorptivity) and 229 nm (71,250 L mol^-1 cm^-1) for its OPA derivative. Glutamic acid showed absorption maxima at 198 nm (84,333.33 L mol^-1 cm^-1) and 216 nm (128,857.14 L mol^-1 cm^-1) for its OPA derivative. The correlation coefficients (R²) for the calibration curves ranged from 0.9954 to 0.9982, indicating a high degree of linearity and reliability of the method. Conclusion: The developed spectrophotometric method provides a reliable, precise, and sensitive approach for quantifying aspartic and glutamic acids. Its application is significant for biochemical analysis and has potential implications in clinical diagnostics, offering a promising tool for neurochemical studies.

New spectrophotometric determination sulfamethoxazole drug via various analytical methods in pharmaceutical formulation

For the determination of sulfamethaxazole (SMZ) in pure and pharmaceutical formulations, new simple sensitive spectrophotometric methods have been devised. The first technique involved forming an ion pair complex between the basic nitrogen of the SMZ medication and Eriochrome black (EBT) in an acidic buffer solution, and extracting the created complex with chloroform to get a persistent reddish-orange colored dye with a maximum wavelength of 490 nm. Beer's law was followed, and 0.9998 was the correlation coefficient., 0.471×104L. mol-1.cm-1was the molar absorptivity, and the detection limit was 0.177 g/mL. Dispersive liquid-liquid extraction (DLLE) is a second method for estimating a trace amount in an aqueous solution product using an ion pair and a UV-visible spectrophotometer with a maximum wavelength of 490 nm. The concentration range was 0.5-6 g/mL, with a correlation coefficient of 0.9995, 0.889×105 L.mol-1.cm-1, a molar absorptivity of ,the detection limit of 0.013 g/L, and a pre-concentration factor of 25 and an enrichment factor of 18.20. Sulfamethaxazole in pharmaceutical formulations was successfully determined using the provided methodology
 

A sustainable data processing approach using ultraviolet-spectroscopy as a powerful spectral resolution tool for simultaneously estimating newly approved eye solution in the presence of extremely carcinogenic impurity aided with various greenness and whiteness assessment perspectives: Application to aqueous humor

Drug impurities are now seen as a major threat to drug safety around the world, especially when it comes to carcinogenic impurities. Here, we present the first spectrophotometric approach for the quantification of lignocaine and fluorescein in the presence of 2,6-xylidine, lignocaine’s carcinogenic impurity. The approach depends on overcoming unresolved bands through a data processing strategy employing 10 affordable, simple, and sensitive spectrophotometric methods. Fluorescein analysis (1–16 μg mL−1) was performed using direct ultraviolet spectrophotometry (D0) at 478 nm; then, the ratio subtraction method allowed the removal of interference caused by the fluorescein spectrum. From the resulting ratio spectra, 2,6-xylidine (40–160 μg mL−1) can be efficiently determined at 280 nm. However, lignocaine (72–320 μg mL−1) was analyzed using different ultraviolet-based methods, including continuous wavelet transform, ratio derivative by Savitzky–Golay filters, mean centering, second derivative of ratio spectra, ratio spectra difference spectrophotometry, extended ratio subtraction, absorbance subtraction, Q-absorbance ratio, and area under the curve. In line with International Council for Harmonization of Technical Requirements for Pharmaceuticals for Human Use (ICH), the presented approach was evaluated by its coefficients of determination, detection limits, quantification limits, and relative standard deviations. Similarly, the developed approach was assessed for whiteness, greenness, and sustainability using five assessment tools, including National Environmental Method Index, Eco-Scale Assessment, Complementary Green Analytical Procedure Index, Analytical Greenness Metric, and RGB12, offering promising results. Owing to the satisfactory analytical performance, besides the sustainability, affordability, simplicity, and cost efficiency of the presented methods, their application for quality control and in situ analysis in minimal-infrastructure laboratories increases, increasing the surveillance potential.

A Simple, Stable, and Highly Sensitive Spectrophotometric Method for the Determination of Arsenic(III) from Different Biological Media in the Presence of Nanosilica-Cysteine Composite

This paper describes a selective and fairly stable colorimetric approach to determine trace amounts of arsenic conjugated with nanosilica-cysteine composite in various aqueous and biological samples in milligram per liter (mg/L) using Leucocrystal Violet (LCV) as a chromogenic reagent. Attenuated total reflectance-Fourier-transform infrared (ATR-FTIR) spectroscopy analysis was applied to characterize the composite. Novelty of this method is dealing with the presence of nanosilica which is reflected in the difficulty of obtaining a clear solution. The maximum absorbance is measured and Beer's law shows linearity over the concentration range of (0.75 to 5.00 mg/L) of As(III) at 590 nm. The molar absorptivity, Sandell’s sensitivity, and detection limit of the method were found to be 6.00 × 105 L/mol.cm, 8.55 × 10-2 μg/cm2, and 0.043 mg/L, respectively. The optimum reaction conditions and other analytical parameters were evaluated. Arsenic was successfully detected in a variety of aqueous and biological samples using the proposed method.

Oxidative Coupling Assay for Mesalazine Determination in Pharmaceuticals and Spiked Human Plasma Utilizing Syringic Acid

This study reports on developing a simple, cost-effective, highly sensitive spectrophotometric method for measuring mesalazine (MSZ). The method utilizes the oxidative coupling of MSZ with syringic acid (4-hydroxy 3,5-dimethoxybenzoic acid) in the presence of dissolved oxygen under alkaline conditions to form a stable indophenol dye with a characteristic blue color, which can be measured at 615 nm. Beer’s law was found to be obeyed over the range of 1.25–50 µg·mL−1, with a molar absorptivity of 0.53 × 104 mol−1·L−1·cm−1. Moreover, the method exhibited excellent sensitivity, with a limit of detection (LOD) of 0.093 µg·mL−1 and a limit of quantitation (LOQ) of 0.282 µg·mL−1. The proposed method was found to be selective, as it could effectively detect MSZ in the presence of certain interfering species. The proposed method was validated according to current ICH guidelines and demonstrated good accuracy, with recoveries ranging between 98 and 100% and a relative standard deviation of less than 0.6%. Overall, this method provides a promising tool for the sensitive and accurate determination of MSZ in its pure form, pharmaceutical formulations, and biological samples.

KINETIC SPECTROPHOTOMETRIC DETERMINATION OF TAPENTADOL

A simple, inexpensive, accurate and sensitive spectrophotometric method and kinetic assay have been established to determine tapentadol in pure form, tablets and urine samples. The method is based on the reaction of tapentadol with ferric ions in an acidic solution in the presence of ferricyanide to give water-soluble Prussian blue dye with a maximum absorption wavelength of 735 nm, with a maximum reaction time of 40 minutes. Several experimental factors affect the colour intensity and stability time approaches. The reaction was identified as a first-order pseudo-reaction by calculating the initial rate, and the results of the fixedtime method (at 30 min) are more suitable for quantification and used to construct the calibration curves. The correlation between concentration and absorbance was linear. Moreover, varies from 2 to 12 μg/mL and has a detection limit of 0.1737 μg/mL and a quantification limit of 0.5264 μg/mL. The molar absorption coefficient and Sandel sensitivity were 1.5484 x 10 4 L.mol-1.cm-1 and 0.01430 μg.cm-2, respectively. A comparison of spectrophotometric data with a well-established fixed time kinetic demonstrated that the fixed time technique offers good accuracy, precision, low detection and quantification limitations, and is time efficient. These procedures were effectively used to analyze tapentadol in its pure form, tablet form, and urine sample, which were not observed in literature before

SPECTROPHOTOMETRIC DETERMINATION OF AMISULPRIDE IN TABLETS BY DIAZOTIZATION COUPLING REACTIONS

A simple and sensitive spectrophotometric methods for assay of amisulpride in pure form and tablets is achieved. Both methods involves the diazotization of amisulpride with nitrite in an acidic medium to produce the corresponding diazonium salt, followed by either coupling with iminodibenzyl (IDB) in acidic medium to give a violet azo dye which showed maximum absorption at 558 nm (method A) or coupling with 7-iodo-8-hydroxyquinoline-5- sulfonic acid (IHQS) in alkaline medium to produce a red azo dye which show maximum absorbance at 522 nm (method B). The two methods have been applied successfully to determine of amisulpride in tablets and also evaluated by applying the standard addition technique

Development of Simple VU Spectrophotometric Method for the Estimation of Bambuterol Hydrochloride in Bulk and Its Formulations

A simple, rapid and highly sensitive spectrophotometric method has developed for the estimation of Bambuterol hydrochloride in bulk and marketed tablet dosage form. In distilled water, Bambuterol showed absorbance at 264nm. Linearity was observed in the conc range of 200-1000 μg/ml (r2 = 0.9990). The assay results were found to be in a good agreement with label claim. The recovery studies were carried at 3 different levels i.e, at 100%, 150%, 200%. The accuracy of the method was conformed by recovery studies of tablet dosage forms and was found to be 96.43% for bambuterol hydrochloride. The method was validated stastically and by good recovery with % RSD is less than 2Thus the proposed method was found to be rapid, specific, precise, accurate and cost-effective quality control tool for the routine analysis of bambuterol hydrochloride in bulk and combined dosage form.

Comparative Spectrophotometric Determination of Neodymium (III), Praseodymium (III), Samarium (III) and Terbium (III) in Aqueous and Micelle Media

This research work titled comparative spectrophotometric determination of neodymium (III), praseodymium (III), samarium (III) and terbium (III)in aqueous and micelle media using schiff base was carried out with the aim to use a simple, rapid and sensitive spectrophotometric method for the determination of Nd (III), Pr (III), Sm(III) and Tb(III) using the Schiff base 2,2′-((1E,1′E)-(1,2-phenylenebis(azanlylidene)bis (methanylylidene))diphenol (BSOPD) as a ligand. Spectral and absorbance measurements were carried out using UV/Visible Spectrophotometer (Jenway model no.: 6305) with 1-cm matched quartz cells. This method of experiment was based on the formation of green coloured complexes, upon the reaction of Nd(III) and Pr(III) and a brown coloured complexes for Sm(III) and Tb(III) having a maximum absorbance of 376, 386, 384 and 380 nm respectively. The comparative analysis of the complexes formed in aqueous and in micellar media were investigated in this study. In the obtained results, it was discovered that, Beer’s law was obeyed in the concentration ranges of 0.001 - 0.02 ppm. The molar absorptivity was found to be in the range of 7,776- 23,197 and 27,087 dm³mol^-1cm^-1 and the Sandell’s sensitivity for the compounds analyzed were in the ranges of 6.13-19.34 g cm^-2. The increase in absorbance in the presence of the surfactants is due to micelle formation. The reactants were bound in a small volume of stern layer of the micelle leading to a greater increase in concentration effect. This effect in concentration reaches a maximum before decreasing due to dilution effect occasioned by increase in metal ion concentration.

Spectrophotometric determination of Trifluoperazine Hydrochloride by oxidative coupling reaction with 4- amino benzoic acid using potassium iodate

A new sensitive spectrophotometric method for the determination of trifluoperazine hydrochloride (TFPH) is developed. The method is based on an oxidative coupling reaction with 4- amino benzoic acid using potassium iodate as oxidizing agent in acidic midium to produce a violet color, soluble in water, stable product absorbs at 550 nm. Beer's law is in the linear range 10 - 80 μg/ml of TFPH. The molar absorptivity, Sandellʼs and detection limit (LOD) are 0.8032×104 liter. mol-1.cm-1, 0.0598 μg/cm2, 0.3882 μg/ml respectively. The RSD value is 0.177 – 0.295 %. This method is applied successfully for the determination of trifluoperazine hydrochloride in pharmaceutical formulations (tablets of salabid) and injection

Spectrophotometric Determination of Procaine Hydrochloride in pharmaceutical preparations Via Oxidative Coupling Reaction

A simple, reliable and sensitive spectrophotometric method for the determination of trace amount of procaine hydrochloride in pure and in pharmaceutical preparations (injections) has been developed. The method is based on the oxidative coupling reaction of procaine hydrochloride with phenothiazine and in the presence of ferric nitrate to form a green-water-soluble dye, which is stable and has a maximum absorption at 610 nm. A graph of absorbance versus concentration shows that beer's law is obeyed over the concentration range of 50-2000 µg of procaine hydrochloride in a final volume of 25 ml or (2-80 µg.ml-1) with a molar absorpitivity of 5.51 x 103 L.mol-1.cm-1, a Sandell sensitivity of 4.28 x 10-2 µg.cm-2, a relative error was less than 1.98% and a relative standard deviation was better than 1.72% depending on the concentration. The optimum conditions for full color development are described and the proposed method was applied satisfactorily to pharmaceutical preparations containing procaine Hydrochloride using standard addition method.

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.

The role of silver nanoparticles synthesized from Brassica olerace for determination of Aspirin in pharmaceutical samples by standard additions method

In this study, silver nanoparticles (Ag NPs) were prepared from Brassica oleracea (BO) leaflet extract (BO-AgNPs) and applied for to determination of Aspirin in pharmaceutical samples through selective and sensitive spectrophotometric standard additions method. The measurements of UV-Visible, X-ray diffraction (XRD), Fourier transform infrared (FTIR) and scanning electron microscopy (SEM) have been used to confirm the formation of BO-AgNPs, revealing a prominent absorption band at 450 nm, crystallinity, and an agglomerated morphology having an average particle size of 29 nm. Aspirin in Acifein, Aspirin, Acylpyrin and Disprin tablets was determined through the complexation with BO-AgNPs, revealing a linear range of 1-10 mg/10 mL and limit of detection (LOD) as 0.09, 0.46, 0.69 and 0.99 mg/10 mL, respectively. An average percent recovery for four samples were found to be 90, 99, 101 and 99 % and relative standard deviation (RSD) as 1.6, 0.6, 0.3 and 1.4, respectively. The suggested method was successfully used for the quantitative analysis of pharmaceutical tablets, which opens up the possibility that Ag NPs could be used to determine biological molecules when interferences from real samples are present.

Spectrophotometric Determination of Vitamin B1 (Thia min Hydrochloride)In Pharmaceutical Preparation by Coupling Reaction with Diazotized Sulfanilic acid.

A simple, accurate and sensitive spectrophotometric method for the determination of vitamin B1 (hiamin hydrochloride) in aqueous solution is described. The method is based on the diazotization of sulfanilic acid followed by coupling with thiamin hydrochloride in the presence of sodium hydroxide to form reddish-brown water soluble dye that is stable and has maximum absorption at ( )",u*: 490nm ).The molarabsorptivity and sandell sensitivity were 7.74 x103 L.mol-l.cm-r and 0.045pg.cm-l respectively. The procedure is developed for bulk thiamin hydrochloride and some of their pharmaceutical preparalions. The are accurate, precise and comparable to the standard method (British pharmacopoeia).

Ion-pair extractive spectrophotometric determination of isopropamide iodide in pharmaceutical formulations and environmental wastewater samples using Bromo phenol blue

A simple, accurate and sensitive spectrophotometric method was developed for the determination of isopropamide iodide in pharmaceutical formulations and environmental wastewater samples. The method was based on the formation of ion-pair between isopropamide iodide and bromophenol blue (BPB). The colored product was extracted into chloroform and measured spectrophotometrically at 600 nm. Beer’s law was obeyed in the concentration range of 2.0-20.0 μg/mL with molar absorptivity and Sandell’s sensitivity of 3.17 × 104 L /mol. cm and 15.15 ng/.cm2 respectively. The relative standard deviation (RSD) is better than 1.5. The method was applied successfully to the determination of isopropamide iodide in environmental wastewater samples and in pharmaceutical formulations (tablets).

Spectrophotometric Determination of Methyl Paraben in Pharmaceutical Formulations by Oxidative Coupling Reaction

A simple and sensitive spectrophotometric method was developed for the determination of Methyl Paraben via oxidative coupling with the 2,4-Dinitrophynel hydrazine in the presence of N-bromosuccinimid in a basic medium, Absorbance of the obtained coloured products was measured at the corresponding optimum wavelengths (600 nm), Beer’s law is obeyed over the concentration of 2.0-20 μg.ml-1, and The molar absorptivity of (6253 L.mole-1.cm-1), Sandell,s sensitity index of (0.02433 µg.cm-2). The detection limits were (0.34 μg.ml-1), with a linear regression correlation coefficient of (0.9947) and recovery range from (98.96–103%). The proposed method has been applied successfully to determine Methyl Paraben in pharmaceutical preparations and cosmetic formulations.