A Green-and-White Integrative Analytical Strategy Combining Univariate and Chemometric Techniques for Quantifying Recently Approved Multi-Drug Eye Solution and Potentially Cancer-Causing Impurities: Application to the Aqueous Humor.

BACKGROUND: Drug impurities are now seen as a major threat to the production of pharmaceuticals around the world and a major part of the global contamination problem, especially when it comes to carcinogenic impurities. OBJECTIVE: We present the first spectrophotometric strategy based on a combination of univariate and multivariate methods as impurity profiling methods for the estimation of lignocaine (LIG) and fluorescein (FLS) with their carcinogenic impurities: 2,6-xylidine (XYL) and benzene-1,3-diol (BZD). METHOD: The data processing strategy depends on overcoming unresolved bands by employing five affordable, accurate, selective, and sensitive methods. The methods applied were a direct UV univariate spectrophotometric analysis (D0) and four multivariate chemometric methods, including classical least squares (CLS), principal component regression (PCR), partial least squares (PLS), and genetic algorithm (GA-PLS). FLS analysis (1-16 µg/mL) was performed using the D0 method at 478 nm; then, the application of the ratio subtraction method (RSM) allowed the removal of interference caused by the FLS spectrum. From the resulting ratio spectra, LIG, XYL, and BZD can be efficiently determined by chemometrics. The calibration set was carefully selected at five concentration levels using a partial factorial training design, resulting in 25 mixtures with central levels of 160, 40, and 3 µg/mL for LIG, XYL, and BZD, respectively. Another 13 samples were applied to validate the predictive ability. RESULTS: The statistical parameters demonstrated exceptional recoveries and smaller prediction errors, confirming the experimental model's predictive power. CONCLUSIONS: The proposed approach was effectively tested using newly FDA-approved LIG and FLS pharmaceutical preparation and aqueous humor. Additionally, it was effectively assessed for whiteness, greenness, and sustainability using five assessment tools. HIGHLIGHTS: With its remarkable analytical performance, sustainability, affordability, simplicity, and cost-efficiency, the proposed strategy is an indispensable tool for quality control and in situ analysis in little-equipped laboratories, increasing the proposed approach's surveillance ability.

Environmentally sustainable DRS-FTIR probe assisted by chemometric tools for quality control analysis of cinnarizine and piracetam having diverged concentration ranges: Validation, greenness, and whiteness studies.

A novel diffuse reflectance fourier transform infrared spectroscopic method accompanied by chemometrics was optimized to fulfill the white analytical chemistry and green analytical chemistry principles for the quantification of cinnarizine and piracetam for the first time without any prior separation in their challenging pharmaceutical preparation, which has a pretty substantial difference in the concentration of cinnarizine/piracetam (1:16). Furthermore, the suggested method was used for cinnarizine/piracetam dissolution testing as an effective alternative to traditional methods. For the cinnarizine/piracetam dissolution tests, we used a dissolution vessel with 900 mL of phosphate buffer pH 2.5 at 37 °C ± 0.5 °C, then the sampling was carried out by frequent withdrawal of 20 µl samples from the dissolution vessel at a one-minute interval, over one hour, then representative fourier transform infrared spectra were recorded. To create a partial-least-squares regression model, a fractional factorial design with 5 different levels and 2 factors was used. This led to the creation of 25 mixtures, 15 as a calibration set and 10 as a validation set, with varying concentration ranges: 1-75 and 16-1000 µg/mL for cinnarizine/piracetam, respectively. Upon optimization of the partial-least-squares regression model, in terms of latent variables and spectral region, root mean square error of cross-validation of 0.477 and 0.270, for cinnarizine/piracetam respectively, were obtained. The optimized partial-least-squares regression model was further validated, providing good results in terms of recovery% (around 98 to 102 %), root mean square error of prediction (0.436 and 3.329), relative root mean square error of prediction (1.210 and 1.245), bias-corrected mean square error of prediction (0.059 and 0.081), and limit of detection (0.125 and 2.786) for cinnarizine/piracetam respectively. Ultimately, the developed method was assessed for whiteness, greenness, and sustainability using five assessment tools. the developed method achieved a greener national environmental method index and complementary green analytical procedure index quadrants with higher eco-scale assessment scores (91), analytical greenness metric scores (0.87), and red-greenblue 12 algorithm scores (89.7) than the reported methods, showing high practical and environmental acceptance for quality control of cinnarizine/piracetam.

An innovative nanoparticle-modified carbon paste sensor for ultrasensitive detection of lignocaine and its extremely carcinogenic metabolite residues in bovine food samples: Application of NEMI, ESA, AGREE, ComplexGAPI, and RGB12 algorithms.

Nowadays, veterinary medicine residues have been viewed as a major threat to food safety worldwide, especially when dealing with carcinogenic residues. Herein, we present the first differential pulse voltammetric method for the quantification of lignocaine and its carcinogenic metabolite 2,6-xylidine residues in bovine food samples, aided by five greenness and whiteness assessment tools, including NEMI, ESA, ComplexGAPI, AGREE, and RGB12. The method depends on the electrochemical oxidation after modification of the carbon paste sensor with recycled Al2O3-NPs functionalized multi-walled carbon nanoparticles. The produced sensor (Al2O3-NPs/MWCNTs/CPE) was characterized using XRD, FT-IR, EDX, SEM, and TEM. As expected, the active surface area and electron transfer processes were accelerated by the modification, resulting in ultra-sensitive quantification with detection limits of 19.00 and 13.94 nM for lignocaine and 2,6-xylidine, respectively. In terms of greenness, whiteness, sustainability, analytical effectiveness, and economic and practical considerations, the proposed method outperforms the reported methods.

Application of different spectrofluorimetric approaches for quantitative determination of acetylsalicylic acid and omeprazole in recently approved pharmaceutical preparation and human plasma.

Acetylsalicylic acid and omeprazole were recently formulated by the new FDA-approved drug Yosprala ® Tablets. This novel combination was prescribed to reduce the risk of myocardial infarction in patients who were at risk for developing peptic ulcer while taking acetylsalicylic acid. In the current work, two different high precision sensitive fluorescence spectroscopic methods were developed for quantitative analysis of the above drugs in pharmaceutical dosage form and spiked human plasma. Acetylsalicylic acid was quantitatively analyzed due to its unique native fluorescence nature. The fluorescence emission of acetylsalicylic acid was quantitatively determined at 404 nm after excitation at 296 nm without any interference from omeprazole. Omeprazole, which has a free terminal secondary amino group, reacted with 4-chloro-7-nitrobenzo-2-oxa-1, 3-diazole (NBD-Cl) by a nucleophilic substitution mechanism to form a highly fluorescent dark yellow fluorophore. Omeprazole was quantitatively analyzed by measuring the emission fluorescence intensity of the dark yellow fluorophore at 535 nm after excitation at 465 nm. Various parameters affecting the described methods were carefully checked and optimized. The calibration curves were found to be linear over the concentration range of 50-1600 ng/ml for acetylsalicylic and 30-2000 ng/ml for omeprazole. The proposed methods were successfully applied to the quantitative analysis of the two drugs in the pharmaceutical dosage form Yosprala ® and in spiked human plasma.

Simultaneous spectrophotometric quantitative analysis of velpatasvir and sofosbuvir in recently approved FDA pharmaceutical preparation using artificial neural networks and genetic algorithm artificial neural networks.

Two chemometric assisted spectrophotometric models were applied for the quantitative analysis of velpatasvir and sofosbuvir in their newly FDA approved pharmaceutical dosage form. The UV absorption spectra of velpatasvir and sofosbuvir showed certain degree of overlap which exhibited degree of difficulty for the choice of certain method provides simultaneous quantitative analysis of the cited drugs. Artificial neural networks and genetic algorithm artificial neural networks were the suitable model for the quantitative analysis of velpatasvir and sofosbuvir in their binary mixture. Experimental design and building the calibration set for the binary mixture were achieved to implement the described models. The proposed models were optimized with the aid of five-levels, two factors experimental design. Spectral region of 380-400 nm was rejected which resulted in 181 variables. GA reduced absorbance matrix to 72 and 36 variables for velpatasvir and sofosbuvir respectively. The models succeeded to estimate the studied drugs with acceptable values of root mean square error of calibration and root mean square error of prediction. The developed models were successfully applied to the quantitative analysis of the two drugs in Epclusa® tablets. The results were statistically compared with another published quantitative analytical method with no significant difference by applying Student t-test and variance ratio F-test.

Application of different spectrofluorimetric methods for determination of lesinurad and allopurinol in pharmaceutical preparation and human plasma.

Lesinurad and allopurinol combination is newly FDA approved for treatment of patients suffering from hyperuricemia associated with uncontrolled gout. In the present work, two different highly sensitive, selective and accurate fluorescence spectroscopic methods were developed for quantitative analysis of lesinurad and allopurinol in their pharmaceutical dosage form without any tedious operation procedure. Lesinurad was quantitatively analyzed based on its unique native fluorescence nature. Lesinurad fluorescence emission was quantitatively determined at 343 nm after excitation at 288 nm without any interference from allopurinol. Allopurinol, has free terminal secondary amino group, reacted with 4-chloro-7-nitrobenzo-2-oxa-1,3-diazole (NBDCl) through nucleophilic substitution mechanism forming highly fluorescent dark yellow fluorophore. Allopurinol was quantitavely analyzed based on measurement the emission fluorescence intensity of the fluorescent dark yellow fluorophore at 535 nm after excitation at 465 nm. Different parameters which affect the described methods of the studied drugs were carefully checked and optimized. Calibration graphs were found to be linear over the concentration range of 0.25-4.0 µg/mL for lesinurad and 0.2-20 µg/mL for allopurinol. The proposed methods were successfully applied for the quantitative analysis of the two drugs in Duzallo® pharmaceutical dosage form and spiked human plasma.

Simultaneous determination of elbasvir and grazoprevir in their pharmaceutical formulation by synchronous fluorescence spectroscopy coupled to dual wavelength method.

In the present study, a sensitive, selective and accurate synchronous fluorescence spectroscopic method was utilized for simultaneous estimation of elbasvir and grazoprevir in their pharmaceutical formulation. The developed method based on measurement of the synchronous fluorescence intensity of the studied drugs at constant wavelength difference (Δλ) = 50 nm. Elbasvir can be determined directly at 312 nm without interference from grazoprevir. Grazoprevir can be determined by application of dual wavelength method by taking the difference in synchronous fluorescence intensity at 390 & 372 nm to remove interference from elbasvir. Calibration graphs were found to be linear over the concentration range of 50-700 ng/mL for elbasvir and 100-900 ng/mL for grazoprevir. The developed method was successfully applied to the quantitative analysis of the two drugs in Zepatier® tablets.

Spectrophotometric determination of lesinurad and allopurinol in recently approved FDA pharmaceutical preparation.

Different spectrophotometic quantitative analytical methods have been developed and applied for quantitative determination of lesinurad and allopurinol in their newly FDA approved pharmaceutical dosage form. lesinurad was quantitatively analyzed based on its unique UV spectra without any mathematical processing step. Direct quantitative analysis was done through its recorded zero-order absorption spectra at 290 nm without any contribution from allopurinol. On the other hand two processing mathematical spectrophotometric methods were applied to enable quantitative analysis of allopurinol through resolving of the recorded overlapping UV spectra between lesinurad and allopurinol. Ratio difference and ratio derivative spectra manipulated methods were enabled successful quantitative determination of allopurinol without any contribution from lesinurad. The described methods were successfully applied for the quantitative analysis of the two drugs in Duzallo ® pharmaceutical dosage form.

Validated Liquid Chromatography-Tandem Mass Spectroscopic Method for Simultaneous Determination of Certain Drugs Used in Cataract Surgery in Rabbit Aqueous Humor.

A sensitive, selective, accurate and precise ultra-high performance liquid chromatography-Tandem mass spectrometry (MS/MS) method was developed and validated for the simultaneous determination of drugs used as eye drops in cataract surgery in aqueous humor. Cataract surgery requires a powerful mydriatic eye drops combination such as cyclopentolate hydrochloride and phenylephrine hydrochloride to dilate the pupil and facilitate eye lens replacement and also requires strong fluoroquinolone antibiotic such as lomefloxacin hydrochloride. The method was performed with positive ion electrospray ionization and the analytes were quantified and monitored on a triple quadrupole mass spectrometer using multiple reaction monitoring scanning mode. Liquid-liquid extraction was used for the purification and preconcentration of analytes from rabbit aqueous humor matrix. Chromatographic elution was performed using an Phenomenex Luna® C18 (150 mm × 2.1 mm, 1.6 µm) column and moxifloxacin hydrochloride as internal standard with a mobile phase consisting of methanol:water:formic acid (70:29:1, by volume) at flow rate of 0.2 mL/min. Satisfactory results regarding linearity, recovery, stability, accuracy and precision of the analytes were obtained. Full validation of the procedure was performed according to the US Food and Drug Administration guidance for industry: bioanalytical method validation and European Medicines Agency (EMA) guideline on bioanalytical method validation.

Stability-Indicating Chromatographic Methods for the Investigation of Ritodrine Hydrochloride Stability and Characterization of the Oxidative Degradation Product.

Two simple and sensitive chromatographic methods were developed and validated for quantitative determination of ritodrine hydrochloride in presence of its oxidative degradation product. The first method depends on densitomeric determination of thin-layer chromatograms of the intact drug in presence of its oxidative degradate. Excellent separation was achieved at 220 nm using a mobile phase of dichloromethane-methanol-glacial acetic acid (15 : 5 : 0.25, v/v/v). The second was an HPLC method, in which efficient separation was carried out on C18 column (150 × 4.6 × 5 µm) using a mobile phase consisting of water: acetonitrile (70,30, v/v) at a flow rate of 1 mL min-1 and UV detection at 220 nm. Beer's law was obeyed in the range of 0.025-0.3 µg/spot and 5-40 µg mL-1 of the intact drug using the two methods, respectively. The proposed methods were validated according to International Conference on Harmonization guidelines and successfully applied for the determination of ritodrine hydrochloride in bulk powder, laboratory prepared mixtures and pharmaceutical dosage form with good accuracy and precision. The results obtained were compared with those of the reported method and were found to be in good agreement.

Posttraining Knowledge Retention among Licensed Cupping Providers in Saudi Arabia.

BACKGROUND: One of the licensing requirements for cupping providers in Saudi Arabia is to attend a compulsory training course that lasts 5 days for non-physicians and 4 days for physicians, irrespective of any previous experience in cupping therapy. The course is conducted by the National Center of Complementary and Alternative Medicine (NCCAM/MOH). As a part of course auditing, the current study aimed to evaluate knowledge retention among licensed cupping providers 1-3 years after passing the official cupping course. METHODS: Licensed cupping providers were invited to attend a continuing medical education activity. Sixty-two attended the continuing medical education activity. Before the event, participants were asked to answer 35 multiple-choice questions taken from the same data bank as the pretest and posttest of the course. The test scores were linked and compared with the pre- and posttest of the training course. RESULTS: A paired t test showed significant differences between the pre- and posttest knowledge scores (mean difference: 224.6 ± 86, p = 0.0001) and between the posttest and follow-up knowledge scores (mean difference: -115.26 ± 103.9, p = 0.0001). The follow-up score was still significantly higher than the pretest score, with a mean difference of 112 (95% CI: 83.66-140.34, p = 0.0001). There was no significant effect of category (physician vs. non-physician) on knowledge retention after controlling for the postcourse score. Gender, the total duration of experience, and total years of experience in cupping did not affect knowledge score retention between the physicians and the non-physicians. CONCLUSION: The official cupping training course of the NCCAM/MOH achieved reasonable knowledge retention. To achieve long-term knowledge retention, refresher training/courses and continuous professional development will be required.

The medical perspective of cupping therapy: Effects and mechanisms of action.

Cupping Therapy (CT) is an ancient method and currently used in the treatment of a broad range of medical conditions. Nonetheless the mechanism of action of (CT) is not fully understood. This review aimed to identify possible mechanisms of action of (CT) from modern medicine perspective and offer possible explanations of its effects. English literature in PubMed, Cochrane Library and Google Scholar was searched using key words. Only 223 articles identified, 149 records screened, and 74 articles excluded for irrelevancy. Only 75 full-text articles were assessed for eligibility, included studies in this review were 64. Six theories have been suggested to explain the effects produced by cupping therapy. Pain reduction and changes in biomechanical properties of the skin could be explained by "Pain-Gate Theory", "Diffuse Noxious Inhibitory Controls" and "Reflex zone theory". Muscle relaxation, changes in local tissue structures and increase in blood circulation might be explained by "Nitric Oxide theory". Immunological effects and hormonal adjustments might be attributed to "Activation of immune system theory". Releasing of toxins and removal of wastes and heavy metals might be explained by "Blood Detoxification Theory". These theories may overlap or work interchangeably to produce various therapeutic effects in specific ailments and diseases. Apparently, no single theory exists to explain the whole effects of cupping. Further researches are needed to support or refute the aforesaid theories, and also develop innovative conceptualizations of (CT) in future.

Simultaneous Determination of Elbasvir and Grazoprevir in Their Pharmaceutical Preparation Using High-Performance Liquid Chromatographic Method.

A high-performance liquid chromatographic method has been developed for simultaneous determination of elbasvir and grazoprevir; two new Food and Drug Administration (FDA) approved drugs. The two drugs were co-formulated for treatment of hepatitis C virus in their combined pharmaceutical dosage form. The chromatographic separation has been achieved using a reversed phase BDS Hypersil C18 column with a mobile phase consists of acetonitrile:methanol (50:50, v/v) at flow rate of 1 mL/min and UV detection at 253 nm. Computational investigation for finding the best stationary phase revealed that C18 column fits better for the simultaneous chromatographic analysis of the studied drugs. Linearity, accuracy and precision have been found to be acceptable over the concentration range of 1-20 µg/mL for the studied drugs. The described method has been successfully applied for simultaneous determination of the studied drugs in their pharmaceutical dosage form.

Spectrofluorimetric determination of acotiamide hydrochloride trihydrate in the presence of its oxidative degradation product.

Acotiamide hydrochloride trihydrate is a novel gastroprokinetic drug which has been recently approved for the treatment of patients with functional dyspepsia. This study presents the first reported to investigate the fluorimetric behavior of acotiamide hydrochloride trihydrate in the presence of its oxidative degradation product. All variables that affect fluorescence intensity were studied and optimized. The described method involved the measurement of native fluorescence of the drug in ethanol at 404 nm after excitation at 326 nm. Calibration plot was found to be linear over the concentration range 0.1-0.9 µg/ml. The specificity of the method has been tested via selective determination of the studied drug in its synthetic mixtures with its degradation product. The proposed method has been successfully applied to the analysis of the drug in its new pharmaceutical dosage form and the results have been statistically compared with the reported HPLC method showing no significant differences by applying t-test and F-test.

Validated Stability Indicating High Performance Liquid Chromatographic Determination of Lesinurad.

Lesinurad is a novel selective uric acid reabsorption inhibitor which has been newly approved for the treatment of the chronic gout. The behavior of lesinurad under various stress conditions (hydrolysis, oxidation, thermal and photolysis) has been investigated as per ICH guidelines. The drug has been found to be labile to acidic hydrolysis, basic hydrolysis and oxidation but stable in neutral, thermal and photolytic conditions. A high performance liquid chromatographic method has been developed for selective determination of the studied drug in the presence of its related degradation products. Good chromatographic resolution has been achieved using a reversed phase BDS Hypersil C18 stationary phase with an isocratic elution of a mobile phase consists of acetonitrile:water (65:35, v/v) at a flow rate of 1 mL/min and UV detection at 290 nm. Two degradation products have been identified by IR and mass spectral scans. The method was validated according to ICH guidelines. The linearity range has been found to be acceptable over the concentration range of 1-20 µg/mL. The developed method has been successfully applied for the estimation of lesinurad in its pharmaceutical dosage form and could be used for the routine analysis of the studied drug in the quality control laboratories.

Simultaneous Spectrophotometric Determination of Elbasvir and Grazoprevir in a Pharmaceutical Preparation.

Three UV spectrophotometric methods have been developed for the simultaneous determination of two new Food and Drug Administration-approved drugs, elbasvir (EBV) and grazoprevir (GRV), in their combined pharmaceutical dosage form. These methods include dual wavelength (DW), classic least-squares (CLS), and principal component regression (PCR). To achieve the DW method, two wavelengths were chosen for each drug in a way to ensure the difference in absorbance was zero from one drug to the other. GRV revealed equal absorbance at 351 and 315 nm, for which the distinctions in absorbance were measured for the determination of EBV. In the same way, distinctions in absorbance at 375 and 334.5 nm were measured for the determination of GRV. Alternatively, the CLS and PCR models were applied to the spectra analysis because the synchronous inclusion of many unreal wavelengths rather than using a single wavelength greatly increased the precision and predictive ability of the methods. The proposed methods were successfully applied to the assay of these drugs in their pharmaceutical formulation. The obtained results were statistically compared with manufacturing methods. The results conclude that there was no significant difference between the proposed methods and the manufacturing method with respect to accuracy and precision.

Simeprevir oxidative degradation product: Molecular modeling, in silico toxicity and resolution by synchronous spectrofluorimetry.

In this article, one of the potential degradation products of the novel antiviral drug simeprevir was isolated and characterized by means of infrared (IR) and mass spectrometry. Moreover, comparative molecular docking, ADMET (absorption, distribution, metabolism, excretion - toxicity) and insilico toxicity prediction studies were applied to evaluate the activity of simeprevir and its degradation product. Furthermore,a simple, accurate and selective second derivative synchronous spectrofluorimetric method was developed for the determination of simeprevir in the presence of its oxidative degradation product.The synchronous fluorescence spectra of both compounds were measured in ethanol at pH 2.0 usingΔλ of 140 nm and the peak amplitude of the second derivative spectra were measured at 442 nm. The method was rectilinear over the concentration range of 0.2 to 2.0 µg/ml and validated according to the ICH (International Conference on Harmonization) guidelines. Moreover, the method was statistically compared to the reverse-phase high-performance liquid chromatography (RP-HPLC) method and good results were obtained.

Spectroflurimetric estimation of the new antiviral agent ledipasvir in presence of sofosbuvir.

A spectroflurimetric method has been developed and validated for the selective quantitative determination of ledipasvir in presence of sofosbuvir. In this method the native fluorescence of ledipasvir in ethanol at 405nm was measured after excitation at 340nm. The proposed method was validated according to ICH guidelines and show high sensitivity, accuracy and precision. Furthermore this method was successfully applied to the analysis of ledipasvir in pharmaceutical dosage form without interference from sofosbuvir and other additives and the results were statistically compared to a reported method and found no significant difference.

Different spectrophotometric methods applied for the analysis of simeprevir in the presence of its oxidative degradation product: Acomparative study.

Five simple spectrophotometric methods were developed for the determination of simeprevir in the presence of its oxidative degradation product namely, ratio difference, mean centering, derivative ratio using the Savitsky-Golay filters, second derivative and continuous wavelet transform. These methods are linear in the range of 2.5-40µg/mL and validated according to the ICH guidelines. The obtained results of accuracy, repeatability and precision were found to be within the acceptable limits. The specificity of the proposed methods was tested using laboratory prepared mixtures and assessed by applying the standard addition technique. Furthermore, these methods were statistically comparable to RP-HPLC method and good results were obtained. So, they can be used for the routine analysis of simeprevir in quality-control laboratories.

Application of different spectrophotometric methods for simultaneous determination of elbasvir and grazoprevir in pharmaceutical preparation.

The first three UV spectrophotometric methods have been developed of simultaneous determination of two new FDA approved drugs namely; elbasvir and grazoprevir in their combined pharmaceutical dosage form. These methods include simultaneous equation, partial least squares with and without variable selection procedure (genetic algorithm). For simultaneous equation method, the absorbance values at 369 (λmax of elbasvir) and 253nm (λmax of grazoprevir) have been selected for the formation of two simultaneous equations required for the mathematical processing and quantitative analysis of the studied drugs. Alternatively, the partial least squares with and without variable selection procedure (genetic algorithm) have been applied in the spectra analysis because the synchronous inclusion of many unreal wavelengths rather than by using a single or dual wavelength which greatly increases the precision and predictive ability of the methods. Successfully assay of the drugs in their pharmaceutical formulation has been done by the proposed methods. Statistically comparative analysis for the obtained results with the manufacturing methods has been performed. It is noteworthy to mention that there was no significant difference between the proposed methods and the manufacturing one with respect to the validation parameters.