A green, robust and fast stability indicating chromatographic method has been developed for concomitant analysis of fluorescein sodium and benoxinate hydrochloride in the presence of their ...degradation products within four minutes. Two different designs including fractional factorial and Box-Behnken designs were implemented for screening and optimization steps, respectively. The optimum chromatographic analysis was achieved using a mixture of isopropanol and 20 mM potassium dihydrogen phosphate solution (pH 3.0) in the ratio 27:73 as mobile phase. The flow rate was 1.5 mL/min and column oven temperature was 40 °C. Chromatographic analysis was performed on Eclipse plus C18 (100 mm × 4.6 mm × 3.5 μm) column with DAD detector set at 220 nm. A linear response was acquired over the range of 2.5-60 μg/mL and 1-50 μg/mL for benoxinate and fluorescein respectively. Stress degradation studies were executed under acidic, basic, and oxidative stress conditions. The method was implemented for quantitation of cited drugs in ophthalmic solution with mean percent recovery ± SD of 99.21 ± 0.74 and 99.88 ± 0.58 for benoxinate and fluorescein respectively. The proposed method is more rapid and eco-friendly compared to the reported chromatographic methods for determination of cited drugs.
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•The first spectrofluorimetric method for determination of favipiravir which is a potential treatment of COVID-19 virus.•The developed method is simple, rapid, robust and ...sensitive.•Experimental design has been applied during optimization to ensure robustness of the method.•The excellent sensitivity of the method allowed the determination of favipiravir in human plasma.•Assessment of greenness of the proposed method using the analytical eco-scale.
The present work describes development of rapid, robust, sensitive and green spectrofluorimetric method for determination of favipiravir (FAV). Different factors affecting fluorescence were carefully studied and Box Behnken Design was applied to optimize experimental parameters. The proposed method is based on measuring native fluorescence of FAV in 0.2 M borate buffer (pH 8.0) at 432 nm after excitation at 361 nm. There was a linear relationship between FAV concentration and relative fluorescence intensity over the range 40–280 ng/mL with limit of detection of 9.44 ng/mL and quantitation limit of 28.60 ng/mL. The method was successfully implemented for determination of FAV in its pharmaceutical formulation with mean % recovery of 99.26 ± 0.87. Moreover, the high sensitivity of the method allowed determination of FAV in spiked human plasma over a range of 48–192 ng/mL. The proposed spectrofluorimetric method was proved to be eco-friendly according to analytical eco-scale.
Abstract
A green, fast and robust solvent-free chromatographic method has been developed for concomitant analysis of ciprofloxacin HCl and metronidazole in bulk powder as well as in dosage form using ...levofloxacin as internal standard (I.S.). Two different designs including fractional factorial (FFD) and Box–Behnken (BBD) designs were implemented for screening and optimization steps, respectively. The optimum chromatographic separation was accomplished using mobile phase composed of 0.13 M sodium dodecyl sulfate and 0.02 M Birij-35 solution adjusted to pH 2.5 using phosphoric acid at a flow rate of 1.3 mL/min and column oven temperature of 40 °C. Chromatographic analysis was performed on X-Bridge (150 mm × 4.6 mm, 5 μm) column with UV detection at 280 nm. A linear response was acquired over the range of 0.4–50 μg/mL for both drugs. The developed method was applied for quantitation of cited drugs in commercially available tablet with mean percent recovery ± SD of 99.45 ± 0.72 and 100.13 ± 0.81 for metronidazole and ciprofloxacin respectively. The method was proven to be green as evaluated by three greenness assessment tools. The run time was 8 min, thus saving time and reagent.
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•For the first time, synchronous spectrofluorimetry coupled was used for determination of OLM &MET.•The developed method showed high sensitivity.•Estimation was done in prepared ...pharmaceutical formulation and spiked human plasma.•The developed method is economic and time saving.
For the first time a spectrofluorimetric method had been achieved for the concurrent analysis of metoprolol succinate (MET) and olmesartan medoxomil (OLM). The approach depended on assessing the first order derivative (1D) of the synchronous fluorescence intensity of the two drugs in aqueous solution at Δλ of 100 nm. The amplitudes of 1D at 300 nm and 347 nm were measured for MET and OLM, respectively. The linearity ranges were 100–1000 ng/mL and 100–5000 ng/mL for OLM and MET, respectively. This approach is uncomplicated, repetitive, quick, and affordable. The results of analysis had been statistically verified. The validation assessments were carried out following the recommendations of The International Council for Harmonization (ICH). This technique could be employed to assess marketed formulation. The method was sensitive with limits of detection (LOD) of 32 ng/ml and 14 ng/mL for MET and OLM, respectively. Limits of quantitation (LOQ) were 99 ng/ml for MET and 44 ng/mL for OLM. So it can be applied to determine both drugs in spiked human plasma within the linearity ranges of 100–1000 ng/mL for OLM and 100–1500 ng/mL for MET.
A reversed-phase RP-HPLC method was developed for the simultaneous determination of metformin hydrochloride (MET), pioglitazone (PIO), and glimepiride (GLM) in their combined dosage forms and spiked ...human plasma. Quality risk management principles for determining the critical method parameters (CMPs) and fractional factorial design were made to screen CMPs and subsequently, the Box-Behnken design was employed. The analytical Quality by Design (AQbD) paradigm was used to establish the method operable design region (MODR) for the developed method depended on understanding the quality target product profile (QTPP), analytical target profile (ATP), and risk assessment for different factors that affect the method performance to develop an accurate, precise, cost-effective, and environmentally benign method. The separation was carried out using a mobile phase composed of methanol: 0.05 M potassium dihydrogen phosphate buffer pH 3.7 with 0.05% TEA (78:22, v/v). The flow rate was 1.2 mL/min. DAD detector was set at 227 nm. Linagliptin (LIN) was used as an internal standard. The proposed method was validated according to The International Council for Harmonization of Technical Requirements for Pharmaceuticals for Human Use (ICH). The assay results obtained by using the developed method were statistically compared to those obtained by the reported HPLC method, and a satisfying agreement was observed.
•New methods were developed for simultaneous determination of olmesartan medoxomil and metoprolol succinate.•Area under the curve and ratio difference spectrophotometric methods were used.•The ...developed methods are simple, accurate and co-friendly with excellent greenness on Eco-scale.•The developed methods are economic and time saving.
The aim of this study is to develop and validate two simple spectrophotometric methods for simultaneous determination of metoprolol succinate (MET) and olmesartan medoxomil (OLM) in tablet form. Method (I) was area under the curve (AUC) method. This approach involved the measuring of the area over a variety of wavelengths. Two wavelength ranges; 213–230 nm and 244–266 nm were chosen for determination of MET and OLM, respectively. Method (II) was ratio difference spectrophotometricmethod. For determination of MET, the ratio spectra were generated using 15 μg/mL OLM as a divisor then the peak to trough amplitudes between 221 nm and 245 nm were displayed versus the corresponding concentrations of MET. For determination of OLM, the peak-to-peak amplitudes between 247 and 293 nm were chosen and found to be directly proportional to OLM concentrations using 15 μg/mL MET as a divisor. The linearity ranges were 2–30 μg/mL and 2–25 μg/mL for MET and OLM, respectively. The assay results showed good mean %recovery ± SD as well as good agreement with that of the reported method. The developed methods were validated according to ICH guidelines. The developed methods are accurate, precise, eco-friendly and could be applied successfully to estimate OLM and MET in their combined dosage form.
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•A highly sensitive spectrofluorometric method was developed for determination of ascorbic acid in tablets.•The reducing characteristics of ascorbic acid were employed to restore ...fluorescence of salicylate in presence of iron (III).•The method showed excellent green characteristics according to the analytical Eco-scale and the green analytical procedure index.•The method was found simple, inexpensive and rapid with high selectivity and sensitivity.
Ascorbic acid has recently been extensively used due to its role in the management of COVID-19 infections by stimulating the immune system and triggering phagocytosis of the corona virus. The currently used spectrofluorometric methods for determination of ascorbic acid require using derivatizing agents or fluorescent probes and suffer from a number of limitations, including slow reaction rates, low yield, limited sensitivity, long reaction times and high temperatures. In this work, we present a highly sensitive spectrofluorometric method for determination of ascorbic acid by switching-on the fluorescence of salicylate in presence of iron (III) due to a reduction of the cation to iron (II). The addition of ascorbic acid resulted in a corresponding enhancement in the fluorescence intensity of iron (III)-salicylate complex at emission wavelength = 411 nm. The method was found linear in the range of 1–8 µg/mL with a correlation coefficient of 0.9997. The limits of detection and quantitation were 0.035 µg/mL and 0.106 µg/mL, respectively. The developed method was applied for the determination of ascorbic acid in the commercially available dosage form; Ruta C60® tablets. The obtained results were compared with those obtained by a reported liquid chromatographic method at 95% confidence interval, no statistically significant differences were found between the developed and the reported methods. Yet, the developed spectrofluorometric method was found markedly greener than the reference method, based on the analytical Eco-scale and the green analytical procedure index. This work presents a simple, rapid and sensitive method that can possibly be applied for determination of ascorbic acid in pharmaceuticals, biological fluids and food samples.
A simple, fast, and ecofriendly spectrofluorometric method was developed and validated for determination of mono sodium glutamate (MSG). The method depended on the reaction between MSG and iron (III) ...salicylate based on ligand exchange mechanism. Addition of MSG turned-on the fluorescent response of iron (III) salicylate at λ
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411 nm. Reaction conditions including reagent concentration, pH, and time were optimized. The method was validated regarding the ICH guidelines. The method determined MSG within the linearity range of 25—250 µM with a coefficient of determination of 0.9967 and a calculated limit of detection of 1.73 µM. Furthermore, the developed method was successfully applied for the determination of MSG in food preparation (instant noodles). The results were compared to those obtained by a published HPLC method using t-test and F-test at 95% confidence interval; no statistically significant difference was found. Based on the analytical Eco-scale and the green analytical procedure index (GAPI), the developed method was assessed to be greener than the published HPLC method. The developed method offered advantages over other spectrophotometric reported methods and was convenient for routine determination of MSG in foodstuffs.
For determination of amlodipine besylate (AML) and olmesartan medoxomil (OLM) at the same time, four UV chemometric spectrophotometric techniques were created and tested in accordance with ICH ...standards. Method (I) was absorption subtraction method (ASM) using two wavelengths, one of which was of AML at 365 nm and the other was the isoabsorptive point of both drugs at 237 nm. Method (II) was ratio subtraction method (RSM) for determination of OLM at λmax = 254 nm by taking the ratio spectrum and subtracting the constant values using 10 μg/mL of AML as a divisor in combination with extended ratio subtraction method (ERSM) to determine AML at λmax = 239 nm using 10 μg/mL OLM as a divisor. Method (III) was dual wavelength method; the wavelengths used to determine OLM were 221 nm and 235 nm, while those used to determine AML were 246 nm and 259 nm. Method (IV) was the second order derivative (2D) spectrophotometric method at 219 nm for OLM and 227 nm for AML. The proposed approaches were used to achieve linearity in the concentration range of 2–25 μg/mL for both drugs. The approaches were found to be uncomplicated, reproducible, efficient, and cost-effective as well as they were successfully used to determine the cited drugs in both laboratory samples and commercial pharmaceutical formulations.
Two simple chemometric spectrophotometric methods; isosbestic point and dual wavelength methods were developed, validated and applied to the determination of metoprolol succinate in presence of ...amlodipine besylate in their binary mixtures and in combined tablet formulation while amlodipine besylate was determined by direct spectrophotometry at λ = 365 nm within linearity range of 2–25 μg/mL. The mean percentage recovery ± SD was 99.921 ± 0.089 for amlodipine besylate. Two proposed chemometric spectrophotometric methods were developed for the spectral resolution of metoprolol succinate in presence of amlodipine besylate without preliminary separation with a linearity range of 2–30 μg/mL metoprolol succinate. The first method depended on measuring the absorbance at the isosbestic point at λ = 226 nm. The mean percentage recovery ± SD was 100.110 ± 0.249 for metoprolol succinate. The second method was dual wavelength method, metoprolol could be determined alone using the absorbance difference between 226 nm and 248.7 nm where the absorbance difference was zero for amlodipine at these two wavelengths. The mean percentage recovery ± SD was 99.734 ± 0.438 for metoprolol succinate using dual wavelength method. The developed methods were validated as per ICH guidelines and were successfully applied to analysis of cited drugs in their synthetic tablet formulation. The results obtained by the developed methods were statistically compared to those obtained by a reported one using t-test and F- test. Good agreement was observed.