Alkali-induced Degradation Product Research Articles

Development and Evaluation of Chemometric Models for the Estimation of Sumatriptan in the Presence of Naproxen and a Degradation Product Using UV Spectrophotometry.

Chemometrics is a discipline that allows the spectral resolution of drugs in a pharmaceutical formulation along with degradation product and it is an alternative to chromatographic methods. Sumatriptan (SUM) is co-formulated with naproxen (NAP) and used in acute migraine attacks. SUM, which has physiological importance, has not been subjected to any stability-indicating chemometric approaches yet, so there is a need for an accurate and safe method for the assay of the cited drug in its preparations. The greenness and blueness assessment was applied using different ecological metrics, including the Green Analytical Procedure Index (GAPI), Analytical Greenness Metric (AGREE), Analytical Eco-Scale (AES) and new "blueness" evaluation using the Blue Applicability Grade Index (BAGI) tool. SUM was determined in pharmaceutical formulation along with NAP and in presence of alkali-induced degradation product with simple and cost-effective multivariate approaches using spectrophotometric data. Three chemometric approaches were applied for the stability-indicating determination of SUM in the presence of NAP. Classical least-squares (CLS), partial least-squaresregression (PLS), and principal components regression (PCR)-three multivariate calibration numerical models that were applied to the UV spectra of the mixtures-were used to achieve the best resolution. Sumatriptan was analyzed with mean accuracies for PLS (100.29% ± 1.318) and for PCR (100.60% ± 1.564). The presented methods were compared and validated for their quantitative analyses. Moreover, statistical comparison between the results obtained by the proposed models and the official methods showed no significant differences. The proposed multivariate calibrations were accurate and specific for quantitative analysis of the studied component. PLS is the best method that has the capacity for qualitative analysis of SUM and it is suitable for routine analysis and stability studies of SUM in QC laboratories. Various ecological assessment metrics confirmed the long-standing eco-friendliness of the suggested models. Severally overlapped mixtures of SUM along with co-formulated drug NAP and an alkali-induced degradation product were analyzed by three chemometric approaches. The analytical performance of PLS and PCR was compared and validated in terms of root-mean-square error of calibration (RMSEC), SE of prediction, and recoveries. PLS gave the highest predicted concentrations with the lowest RMSEC and root-mean-square error of prediction. The standard addition was applied for accuracy assessment and the results were compared to those of official methods. Proposed models determined SUM in synthetic mixtures and pharmaceutical formulation in QC laboratories and stability studies. Ecological evaluation tools for measuring the environmental friendliness of chemicals were utilized for the first time in the analysis of SUM.

Different spectrophotometric methods for simultaneous quantitation of Vericiguat and its alkaline degradation product: a comparative study with greenness profile assessment

Investigations concerning novel drugs and their induced degradation products are necessary for clinical research and quality control in the pharmaceutical industry. Four spectrophotometric techniques have been performed for simultaneous quantitation of Vericiguat (VER) and its alkali-induced degradation product (ADP) without prior separation. Method A is a dual wavelength method (DW) that estimates the absorbance difference at 314–328 nm, and 246–262 nm for VER and ADP; respectively. Method B uses a ratio difference method (RD) to estimate the ratio spectrum’s amplitude difference (DP318-342) and (DP284-292) for VER and ADP; respectively. Method C uses a first derivative ratio method (1DD) to estimate the peak ratio spectrum amplitude of the first derivative at 318 and 275 nm for VER and ADP; respectively. Method D uses the mean centering of the ratio spectra (MCR) to estimate amplitude values for VER and ADP at 337 and 292 nm; respectively. In a concentration range of 5.00–50.00 µg/mL for VER and 5.00–100.00 µg/mL for ADP, the methods were validated following ICH criteria and utilized to estimate VER in bulk and its dosage form. The methods’ greenness was assessed via three tools: the green analytical procedure index (GAPI), analytical eco-scale, and analytical greenness assessment (AGREE).

Greenness profile and whiteness assessment of the stability-indicating HPLC method for the assay of levetiracetam

Adoption of green analytical techniques has been one of the primary goals of the analytical chemistry community over the past years. The reduction of waste generated during sample preparation or analysis is the primary objective of green analytical chemistry (GAC). For the purpose of determining levetiracetam (LEV) in the presence of its alkali-induced degradation product, an accurate, selective, and green stability-indicating reversed phase HPLC technique with UV detection has been devised and validated in the current work. The mobile phase consists of phosphate buffer (pH 3.1) and acetonitrile (87:13 v/v) at the flow rate of 1.0 mL/min, and UV detection was carried out at 210 nm. The stationary phase was Lichrosorb RP-18 (250×4.6 mm i.d., 5 μm particle size) column at 25 °C, in an isocratic mode. The method provided satisfactory resolution and sensitivity, with retention times of (5.6±0.01) minutes for the intact drug and (6.9±0.01) minutes for the alkali-induced degradation product. Different greenness assessment tools, such as the green analytical procedure index (GAPI), Analytical greenness metric (AGREE), and Analytical Eco-Scale (AES), confirmed the proposed approaches' eco-friendliness. The recently launched White Analytical Chemistry (WAC) was also designed to assess the whiteness qualities. The method can be applied for the assay of the cited antiepileptic agent in its formulation in quality control laboratories.

Evaluation of the Efficiency of Smart Stability-Indicating Spectrophotometric Methods Based on Mathematical and Statistical Processing of the Obtained Results Via Different Manipulating Pathways

Background: Smart different stability-indicating spectrophotometric methods have been established for the assay of chlordiazepoxide and clidinium bromide without the intervention of alkaline degradate of clidinium via various and different manipulating pathways without previous separation steps. Objective: The specificity of the established methods was inspected by analysing mixtures of cited drugs in the existence of the alkali-induced degradation product. Methods: These methods were employed either on scanned zero-order absorption spectra using absorbance subtraction, dual wavelength and Q-absorbance ratio or the amplitudes of the ratio spectra of zero-order absorption spectra like amplitude modulation and by derivative techniques to the ratio spectra as a derivative ratio method. In addition, the absorbance of the recovered zero-order absorption spectra was applied by successive ratio subtraction coupled with constant multiplication. Finally, the pathway depends on the amplitudes of the derivative spectra, successive derivative subtraction coupled with constant multiplication. The ranges of linearity were (1-12µg/mL) for chlordiazepoxide and (3- 12µg/mL) for clidinium bromide. Results: The outcomes achieved by the prospective methods were in consent with those of the official and reported methods when statistically compared using student’s t test, F-test and one-way ANOVA where no significant difference was detected with suitable precision, proving the absence of any important difference in accuracy and precision between them. They were confirmed in accordance with International Conference on Harmonization guidelines. Conclusion: The established methods can be considered as alternative methods for the routine determination of this fixed dose combination with minimum sample preparation.

Development and validation of different chemometric-assisted spectrophotometric methods for determination of cefoxitin-sodium in presence of its alkali-induced degradation product

This work, introduces different powerful chemometric methods for determination of cefoxitin-sodium in presence of its alkali-induced degradation product without prior separation steps, dubbed; Principal component regression, Partial least squares with and without variable selection (Genetic Algorithm), Artificial neural network with and without variable selection (Genetic Algorithm), and Classical least square. The predictive abilities of the models were tested and the results proved that proposed methods were successfully applied for the determination of cefoxitin-sodium in its pure form and in its powder for injection.

Novel Stability-Indicating Chemometric-Assisted Spectrophotometric Methods for the Determination of Chlordiazepoxide and Clidinium Bromide in the Presence of Clidinium Bromide's Alkali-Induced Degradation Product.

Two simple and accurate chemometric-assisted spectrophotometric models were developed and validated for the simultaneous determination of chlordiazepoxide (CDZ) and clidinium bromide (CDB) in the presence of an alkali-induced degradation product of CDB in their pure and pharmaceutical formulation. Resolution was accomplished by using two multivariate calibration models, including principal component regression (PCR) and partial least-squares (PLS), applied to the UV spectra of the mixtures. Great improvement in the predictive abilities of these multivariate calibrations was observed. A calibration set was constructed and the best model used to predict the concentrations of the studied drugs. CDZ and CDB were analyzed with mean accuracies of 99.84 ± 1.41 and 99.81 ± 0.89% for CDZ and 99.56 ± 1.43 and 99.44 ± 1.41% for CDB using PLS and PCR models, respectively. The proposed models were validated and applied for the analysis of a commercial formulation and laboratory-prepared mixtures. The developed models were statistically compared with those of the official and reported methods with no significant differences observed. The models can be used for the routine analysis of both drugs in QC laboratories.

Development and Validation of Spectrophotometric Methods Manipulating Ratio Spectra for Determination of Tetramisole Hydrochloride in the Presence of its Alkali-Induced Degradation Product

Development and Validation of Spectrophotometric Methods Manipulating Ratio Spectra for Determination of Tetramisole Hydrochloride in the Presence of its Alkali-Induced Degradation Product

Quantitative Estimation and Validation of Rafoxanide in Presence of its Alkali-Induced Degradation Product by Different Spectrophotometric Methods

Objective: Development and validation of four simple, accurate, selective and sensitive UV spectrophotometric methodsfor the determination of rafoxanide in the presence of its alkali-induced degradation product without preliminary separation. Methods: (A) Dual wavelength method, where the difference in absorbance were calculated at 242 and 281 nm. (B) Area under the curve method,where area under the peak were measured at wavelength ranges (225-235 nm) and (275-295 nm). (C) Bivariate method, where the absorbance values were measured at selected wavelengths 250 and 280 nm. (D) First derivative method, whereThe amplitudes were measured at 253 nm. Results: Good linearity was found in the concentration range of 2.5–25 μg/mL for all the methods. The specificity of the methods were assessed by analysing synthetic mixtures containing the drug and its degradation product. Methods are validated as per ICH guidelines and accuracy, precision, repeatability and robustness are found to be within the acceptable limit. Conclusion: The proposed methods have been found to be accurate, precise and can be used for determination of the drug in pure form and pharmaceutical formulations as well as in the presence of its degradation product without any preliminary separation steps.

Development and Validation of Spectrophotometric Methods for Quantitative Estimation of Oxfendazole in Presence of Its Alkali-induced Degradation Product: A Comparative Study

Objectives:This study aimed to develop and validate three simple, accurate, selective, reproducible and sensitive spectrophotometric methods for the determination of oxfendazole in the presence of its alkali-induced degradation product without preliminary separation. Methods: (A) first derivative spectrophotometry (1D) method at 298.9 nm, (B) first derivative of ratio spectra (1DD) method at 295.4 nm and (C) area under the curve (AUC) method at wavelength ranges of (290-294 nm) and (297-301 nm). All methods were applied in the range of (1-10µg mL-1). Results: These methods were validated and successfully applied for determination of oxfendazole in Unifendazole® suspension. The obtained results were statistically compared with those of the reported method by applying t-test and F-test at 95% confidence level and no significant difference was observed regarding accuracy and precision.Conclusion: The proposed methods are simple, rapid, economic, accurate and precise to determine oxfendazole in the presence of its alkali-induced degradation product without previous separation steps.

TLC-densitometric and first derivative spectrophotometric methods for determination of cefoxitin-sodium in presence of its alkali-induced degradation product

Two simple and accurate methods were developed for quantitative estimation of cefoxitin sodium in presence of its open ring alkali-induced degradation product. The first method was based on TLC separation of the drug from its alkali-induced degradation product followed by densitometric measurement of the intact drug at 254nm. The proposed method obeys Beer’s law in range (1–20µg/band). The second method was first derivative (1D) spectrophotometric method; was based on measurement of amplitude of first order spectra of cefoxitin sodium (in the range of 4–36µgmL−1) at 282nm which showed zero crossing point of its degradation product. The two methods were validated according to ICH guideline for accuracy, precision and were successfully applied for the determination of the drug in pure form and pharmaceutical preparation in presence of its alkali-induced degradation product.

Various Spectrophotometric Methods for Quantitative Estimation of Vinpocetine in the Presence of its Alkali-induced Degradation Product: A Comparative Study

Four simple, accurate, selective, reproducible and sensitive spectrophotometric methods have been developed and validated for the determination of vinpocetine in presence of its alkali-induced degradation product without preliminary separation. These methods include (A) bivariate, (B) second derivative, (C) ratio difference and (D) mean centering of ratio spectra method. These methods were validated according to the ICH guidelines and successfully applied for the determination of vinpocetine in Cavinil ® tablets. The obtained results were statistically compared with those of the reported method by applying t-test and F-test at 95 % confidence level and no significant difference was observed regarding accuracy and precision.

Reversed-Phase Liquid Chromatographic Method for Determination of Daclatasvir Dihydrochloride and Study of Its Degradation Behavior

A simple and selective reversed-phase stability-indicating liquid chromatographic method has been developed and validated for the determination of daclatasvir in drug substance and drug product. Daclatasvir was subjected to acidic, alkaline, oxidative, thermal and photo-degradation study. The LC method was based on isocratic elution of daclatasvir and its degradation products on a reversed-phase C18 Hypersil column using a mobile phase consisting of phosphate buffer (10 mM, 1 mL triethylamine L−1): acetonitrile (60:40 v/v) at a flow rate of 2 mL min−1. Quantitation was achieved with UV detection at 312 nm. Linearity, accuracy, and precision were found to be acceptable over the concentration range of 0.75–120 μg mL−1, with regression coefficient value of 0.9999, and with limit of detection and quantitation of 0.148 and 0.447 μg mL−1, respectively. Peak purity was checked for principle drug and its alkali induced degradation product, and the pathway of alkaline hydrolysis of daclatasvir was suggested by LC/MS.

Stability Indicating Spectrophotometric Methods for the Determination of Cefoxitin Sodium in Pure form and in Pharmaceutical Preparations

Four simple, accurate and precise stability-indicating spectrophotometric methods were developed and validated for the simultaneous determination of cefoxitin sodium in presence of its alkaliinduced degradation product without prior separation namely; Q-analysis, absorbance subtraction, absorbance ratio, and amplitude modulation. These methods were validated for accuracy and precision. The four proposed methods were successfully applied for the determination of the cited drug in pure form and in pharmaceutical preparation also in the presence of its alkaline degradation product. The obtained results were statistically compared with those of a reported method. The comparison showed that there are no significant differences between the proposed methods and the reported method.

Validated Stability-Indicating Chromatographic Methods for the Determination of Chlordiazepoxide and Clidinium Bromide in the Presence of its Alkali-Induced Degradation Product: Kinetic Study

Accurate, simple and selective stability-indicating reversed phase HPLC and TLC-densitometric methods with UV detection have been developed and validated for simultaneous determination of chlordiazepoxide (CDZ) and clidinium bromide (CDB) in the presence of its alkali-induced degradation product (DEG). Successful separation of the drugs from the degradation product was achieved. For the RP-HPLC method, the stationary phase was ACE-126-2546 AQ C-18 (250 × 4.6 mm i.d., 5 μm particle size) column at 25 °C, in an isocratic mode, using mobile phase containing a mixture of 25 mM ammonium acetate (pH 5.4): acetonitrile in the ratio of (20:80, v/v), at the flow rate of 1.0 mL min−1 and UV detection was performed at 222 nm. The retention times were (4.13 ± 0.01) and (8.5 ± 0.01) min for CDZ and CDB, respectively. For the TLC-densitometric method, the separation was performed using a stationary phase of precoated Silica Gel G/UV254 and mobile phase composed of a mixture of ethyl acetate: methanol: ammonia (8:3:1, v/v/v) and scanned at 222 nm. The R f values were (0.79 ± 0.02) and (0.11 ± 0.01) for CDZ and CDB, respectively. The linearity graphs for CDZ and CDB, respectively, were found to be linear over (0.5–40) μg mL−1 and (2–45) μg mL−1 with mean percentage recoveries (99.69 ± 0.836) and (99.28 ± 1.838) for RP-HPLC method and (1–14) μg band−1 and (0.5–10) μg band−1 with mean percentage recoveries (100.00 ± 0.782) and (100.19 ± 1.010) for TLC-densitometric method. A comparative study of different analytical validation parameters such as accuracy, precision, specificity and robustness were conducted. The obtained results were statistically compared with those of the official and reported methods; using Student’s t test, F test and one-way ANOVA, showing no significant difference with high accuracy and good precision. The proposed RP-HPLC method was also used to study the kinetics of the alkaline hydrolysis of clidinium bromide that was found to follow pseudo-first order kinetics. The t 1/2 was 8.5729 min while k (the degradation rate constant) was 0.0808353 min−1.

Determination of Cefoxitin Sodium in the Presence of Its Alkali-induced Degradation Product Through Different Ratio Spectra Manipulating Methods

Four simple, accurate and precise stability-indicating spectrophotometric methods manipulating ratio spectra were introduced for determination of cefoxitin sodium in presence of its alkali-induced degradation product without prior separation more specifically; ratio difference, ratio derivative, mean centering and ratio subtraction. The methods were validated for accuracy, precision. The four proposed methods were successfully applied for the determination of cefoxitin sodium in pure form and in its pharmaceutical preparation. Results obtained were statistically analyzed and compared with those of a reported method, no significant differences between the proposed methods and the reported method.

Spectrophotometric Quantitative Estimation and Validation of Cefadroxil Monohydrate in Presence of its Alkali-Induced Degradation Product

Five simple, accurate, selective and sensitive UV spectrophotometric methods have been developed and validated for the determination of cefadroxil monohydrate in the presence of its alkali-induced degradation product without preliminary separation. These methods include ratio subtraction, absorbance subtraction, amplitude modulation, dual wavelength and simultaneous equation method. These methods were validated and successfully applied for determination of cefadroxil monohydrate in Duricef® capsules. The obtained results were statistically compared with those of the reported method by applying t-test and F-test at 95 % confidence level and no significant difference was observed regarding accuracy and precision.

Development and Validation of Stability Indicating Spectrophotometric Methods for Determination of Sulbutiamine in Tablet Dosage Form

Five sensitive, selective and precise stability-indicating spectrophotometric methods for the determination of Sulbutiamine (SUL) in the presence of its alkali-induced degradation product (DEG) were developed and validated. Method A is differential dual wavelength (D1DWL) applied in the analysis of SUL in binary mixture via its first derivative spectra using the difference between two points with equal amplitudes in the alkali-induced degradation product, thus DEG acts as zero contribution. Method B is second derivative spectrophotometry (D2), which allowed the determination of SUL at 300.0 nm. Method C is second derivative of the ratio spectra (DD2) in which SUL was determined by measuring the peak amplitude at 301.0 nm. Method D is the ratio difference spectrophotometry (RD), where the difference between amplitudes of the absorbance ratio spectra at 237.2 and 274.0 nm were recorded and Method E; Ratio subtraction (RSM) where the zero order spectra of pure SUL were extracted from their laboratory prepared mixtures, and consequently SUL can be analyzed at its maxima. The linearity for SUL was obtained within concentrations ranging from 5.00 - 50.00 μg/mL with percentage recovery of 100.58 ± 0.98, 99.62 ± 1.16, 100.70 ± 1.38, 100.06 ± 1.00 and 99.56 ± 1.00 for the five methods, respectively.

First derivative spectrophotometric and LC determination of benoxinate hydrochloride and its degradation products

Two methods are presented for the determination of benoxinate HCl and its acid and alkali-induced degradation products using first derivative ( 1 D) spectrophotometry with zero-crossing measurements and liquid chromatography. Benoxinate HCl was determined by measurement of its first derivative amplitude in mcllvaine’s-citric acid phosphate buffer pH 7.0 at 268.4 and 272.4 nm in the presence of its alkali- and acid-induced degradation products, respectively. The acid- and alkali-induced degradation products were determined by measurement of their first derivative amplitude in the same solvent at 307.5 nm. The LC method depends upon using a μ bondapak CN column with a mobile phase consisting of acetonitrile–water–triethylamine (60:40:0.01, v/v) and adjusted to apparent pH 7. Quantitation was achieved with UV detection at 310 nm based on peak area. The proposed methods were utilized to investigate the kinetics of the acidic and alkaline degradation processes at different temperatures. The pH-rate profile of degradation of benoxinate HCl in Britton–Robinson buffer solutions was studied.

Applications of Spectrometric Full Spectrum Quantitation (FSQ) Software for Multicomponent Analysis and Stability Studies of Pharmaceuticals

ABSTRACT A rapid, simple, accurate and specific spectrophotometric procedure for analysis of multi-component mixtures and for assessment of drug stability in pharmaceutical products has been described. The proposed method relies on the application of the spectrophotometric full spectrum quantification (FSQ) software to overcome severe spectral overlap and to permit measurement of the individual components in mixtures with satisfactory degree of accuracy and precision. The potential of FSQ software for multicomponent analysis was elucidated by analyzing complex mixtures of highly overlapping spectra (aspirin/caffeine/salicylic acid) and mixtures of structurally similar compounds (cephalexin/ cephradine) and (ceftriaxone/ ceftazidime /cefotaxime). Furthermore, the robustness of the FSQ for stability studies was assessed by analyzing chloramphenicol in presence of its alkali-induced degradation products and famotidine in presence of its acid-induced degradation products. The validity of FSQ software for multicomponent analysis and stability studies was evaluated by comparing the results with those of HPLC methods. Statistical analysis indicated that the FSQ and HPLC data were consistent, however the FSQ method is faster, easier and more reliable.

FSQ spectrophotometric and HPLC analysis of some cephalosporins in the presence of their alkali-induced degradation products

Accurate and precise spectrophotometric full spectrum quantitation (FSQ) and high-performance liquid chromatography (HPLC) procedures for the quantitation of some selected cephalosporins, namely, cefotaxime, ceftazidime and ceftriaxone in the presence of their alkali-induced degradation products and in commercial injections have been described. The degradation products or formulation excipients did not interfere in the analysis. The spectrophotometric method was based on the use of FSQ software of multicomponent analysis for simultaneous determination of the examined antibiotics in the presence of their alkali-induced degradation products. The HPLC procedure was based on resolution of cefotaxime or ceftazidime or ceftriaxone from the alkali-induced degradation products using an ODS column and mobile phase composed of acetonitrile-ammonium acetate buffer solution (0.1 M) in a ratio 10:90 (pH 7.5) with peak detection at 270 nm using a diode array detector. The collected data proved that both procedures were of comparable accuracy and precision, however, the HPLC method was of higher sensitivity ( ⪡ 1 μg/ml) compared to the FSQ method. Accelerated stability studies of cefotaxime, ceftazidime and ceftriaxone in aqueous solutions (pH 2–10) using the HPLC method indicated that the degradation of the antibiotics followed pseudo-first-order kinetics. The rate constant-pH profiles showed that the antibiotics were relatively stable over the pH range 4–6 with optimum stability at pH 5. The extrapolated shelf-life (t 90) values as determined from Arrhenius plots at pH 5 and 25°C were 6.56, 2.14 and 0.88 h for cefotaxime, ceftazidime and ceftriaxone, whereas these values were found to be 15.0, 3.62 and 2.14 h, respectively at 4°C.