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

BACKGROUND: Chemometrics is a discipline that allows the spectral resolution of drugs in a pharmaceutical formulation along with degradation product and it is as an alternative to chromatographic methods. OBJECTIVE: 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 accurate and safe method for the assay of the cited drug in their preparation. 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. The greenness and blueness assessment was applied using different ecological metrics, including green analytical procedure index (GAPI), analytical greenness metric (AGREE), analytical eco-scale (AES) & new "blueness" evaluation using BAGI tool, respectively. METHODS: Three chemometric approaches were applied for the stability-indicating determination of SUM in presence of NAP. Classical least squares (CLS), Partial least squares (PLS) and Principal components regression (PCR), three multivariate calibration numerical models that were performed on the UV- spectra of the mixtures, were used to achieve the best resolution. RESULTS: 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. CONCLUSION: 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 it in quality control laboratories. Various ecological assessment metrics confirmed the long-standing eco-friendliness of the suggested models.

Determination of Clomipramine using eco-friendly solid-contact ionophore-doped potentiometric sensor.

INTRODUCTION: Clomipramine is a tricyclic antidepressant acting as a serotonin reuptake inhibitor. Its maximum plasma concentration (Cmax) is 13-310 ng/mL, the therapeutic range is 220-500 ng/mL and its toxic effect appears in doses above 900 ng/mL. OBJECTIVES: The fabrication of eco-friendly solid-contact ion-selective electrodes to evaluate the concentration of Clomipramine in different matrices based on disposable screen-printed carbon electrode. METHODS: Disposable screen-printed carbon electrode was utilized as a substrate to fabricate the proposed sensors. The sensors were optimized to determine Clomipramine using calix[4]arene as an ionophore into PVC polymeric membrane to enhance selectivity towards the target analyte. The solid-contact sensor potential stability was improved by the incorporation of graphene nanoparticles transducer layer. RESULTS: The sensors were assessed as per the IUPAC recommendations. The linearity range was 1 × 10- 2 to 1 × 10- 5.3 M. The sensors were successfully applied to determine CLM in the pharmaceutical formulation. Furthermore, the ion selective electrodes were applied for Clompiramine assay in spiked plasma for the purpose of Point-of-Care testing to be a diagnostic tool for therapeutic monitoring of the cited central nervous system agent. The findings were statistically compared to the reported method showing no statistically significant difference. CONCLUSION: This work was concerned with developing a green analytical method for the determination of Clomipramine. The proposed SC-ISE was mixed with graphene nanocomposite transducer interlayer. The graphene layer succeeded in preventing the formation of an aqueous layer so resulted in a stable, reproducible standard potential besides the rapid response time.

Comparison of self-perceived competence of recent dental graduates from the Universities of Otago and Dalhousie.

INTRODUCTION: This study investigates and compares the self-perceived competencies of recent dental graduates from the University of Otago (UoO) (Dunedin, New Zealand) and Dalhousie University (DU) (Nova Scotia, Canada). MATERIALS AND METHODS: A validated survey was emailed to recent graduates from the UoO (December 2019) and DU (May 2020). Chi-squared statistical analysis examined the differences between groups. RESULTS: The response rate was 73% from the UoO class and 75% from the DU class. Out of 59 competencies, 11 items showed a significant difference. Orthodontics and the surgical aspects of dentistry were the main areas where significant differences have been observed between the two cohorts. Out of the four items in orthodontics, a significantly higher proportion of DU graduates felt more competent than graduates from UoO in three items ("performing orthodontic treatment planning," "performing space maintenance/regaining" and "performing orthodontic full-arch alignment"; p < .001). Similarly, graduates from DU felt significantly more competent in three of the eight items in the oral and maxillofacial surgery domain ("managing complications of oral surgery," "performing soft-tissue biopsies" and "managing trauma to the dentofacial complex"; p < .001), all requiring surgical training and skills. CONCLUSION: Of the differences identified, graduates from DU reported higher levels of self-perceived competence compared with their UoO counterparts, especially in the orthodontics and oral and maxillofacial surgery domains. This could be because DU students have more practice in these specialties during their training. The results suggest that increased exposure for UoO students in these areas may be beneficial to their self-perceived competence.

Smart Eco-Friendly Spectrophotometric Methods Resolving Highly Overlapping Spectra: Application to Veterinary Antibiotic Injections.

BACKGROUND: Over the last few years, mathematical manipulation has proved to be a very powerful means of successfully resolving severely overlapped spectra for various multicomponent mixtures. OBJECTIVE: Smart and environmentally friendly spectrophotometric determination approaches were used for two binary mixtures of fixed dose veterinary injections containing flunixin meglumine (FLU) combined with either florfenicol (FLR), or oxytetracycline HCl (OXY). METHODS: Regarding the first mixture, both FLU and FLR were determined by three successive resolution techniques, which were; constant multiplication coupled with spectrum subtraction (CM-SS), derivative ratio (DD1), and ratio difference (RD), and two progressive resolution techniques which were absorbance subtraction (AS) and amplitude modulation (AM). Also, graphical representation of concentration of the two drugs through concentration value (CNV) method was also applied. Concerning the second mixture, both FLU and OXY showed severely overlapped spectra and a comparative study was conducted for the determination of each drug by constant center (CC), ratio subtraction via amplitude difference coupled with spectrum subtraction (RS/AD-SS), constant value via amplitude difference (CV-AD), and advanced concentration value (ACV) methods. RESULTS: Calibration graphs of the first mixture were linear over the range 5-40 µg/mL for FLU, and 3-40 µg/mL for FLR. The proposed methods overcame the problem of the overlapped spectra and the presence of a minor component in the mixture. Regarding the second mixture, calibration graphs were linear over the range 2.5-24 µg/mL for FLU and 4-28 µg/mL for OXY. CONCLUSION: The proposed methods were successfully validated as per International Council for Harmonization (ICH) guidelines. The obtained results were statistically compared with the official or reported methods, showing no significant difference concerning accuracy and precision. The methods were evaluated for greenness by three different assessment tools: NEMI, analytical ecoscale, and GAPI. HIGHLIGHTS: The methods were successfully applied for the simultaneous determination of the two combinations in synthetic mixtures and their marketed antibiotic veterinary injections: Megluflor® and Floxon®.

Comparative Study for the Assay of Plant Derived Chemicals in Pharmaceutical Formulation Using Methods Dependent on Factorized Spectra.

BACKGROUND: Modern built-in spectrophotometer software supporting mathematical processes provided a solution for increasing selectivity for multicomponent mixtures. OBJECTIVE: Simultaneous spectrophotometric determination of the three naturally occurring antioxidants-rutin(RUT), hesperidin(HES), and ascorbic acid(ASC)-in bulk forms and combined pharmaceutical formulation. METHOD: This was achieved by factorized zero order method (FZM), factorized derivative method (FD1M), and factorized derivative ratio method (FDRM), coupled with spectrum subtraction(SS). RESULTS: Mathematical filtration techniques allowed each component to be obtained separately in either its zero, first, or derivative ratio form, allowing the resolution of spectra typical to the pure components present in Vitamin C Forte® tablets. The proposed methods were applied over a concentration range of 2-50, 2-30, and 10-100 µg/mL for RUT, HES, and ASC, respectively. CONCLUSIONS: Recent methods for the analysis of binary mixtures, FZM and FD1M, were successfully applied for the analysis of ternary mixtures and compared to the novel FDRM. All were revealed to be specific and sensitive with successful application on pharmaceutical formulations. Validation parameters were evaluated in accordance with the International Conference on Harmonization guidelines. Statistical results were satisfactory, revealing no significant difference regarding accuracy and precision. HIGHLIGHTS: Factorized methods enabled the resolution of spectra identical to those of pure drugs present in mixtures. Overlapped spectra of ternary mixtures could be resolved by spectrum subtraction coupled FDRM (SS-FDRM) or by successive application of FZM and FD1M.

When is it safe to eat different broiler chicken tissues after administration of doxycycline and tylosin mixture?

Residues of veterinary drugs in poultry meat have serious health effects on humans (e.g., antimicrobial resistance, carcinogenicity, and hypersensitivity), which make the control of veterinary drug residues an important parameter in ensuring consumer protection.  This work was performed to quantitatively determine two co-formulated anti-infective veterinary agents, tylosin tartrate (TYT) and doxycycline hydrochloride (DOX) in different tissues of broiler chickens (liver, muscles, and fat) using high performance liquid chromatography. The chicken was treated with the recommended dose of a binary mixture of the drugs (Tydovet). Moreover, the study aimed to estimate the withdrawal time of both drugs in chicken tissues. The analysis was done by solvent extraction and solid-phase extraction for clean-up of samples from the tissue matrix, followed by liquid chromatographic determination of the cited drugs with UV-detection. Residue decline with time was tracked, and both antibiotics were found to be more persistent in liver tissues than other tissues (muscle and fat). The effect of freezing and cooking was investigated on tissue residue levels. While freezing had little effect on the concentration of both antibiotics; cooking, as anticipated, led to a marked decline. Therefore, it is recommended to pay attention to the proper withdrawal periods before marketing to ensure the hygienic suitability of broilers edibles for safe human consumption. PRACTICAL APPLICATION: This novel study measures tylosin and doxycycline residues simultaneously in different tissues (muscle, fat, and liver) after administration of Tydovet powder to the broiler chicken. Residues in fat persisted for a longer time than in muscle in case of TYT, whereas the reverse was noticed in DOX.

A Thorough HPLC Assay of Quaternary Veterinary Formulation coupled with Environmental Assessment Tool.

A new and accurate reversed phase HPLC method with UV detection has been established for any veterinarian analyst for simultaneous determination of a veterinary quaternary mixture of sulphadimidine sodium (SDS), sulphaquinoxaline sodium (SQS), diaveridine (DVD) and vitamin K3 (VTK3) in their formulation. The stationary phase was SEA C18 column (250 × 4.6 mm i.d., 5 µm particle size) at 25°C with an isocratic mode, using a mobile phase containing a mixture of methanol:acetonitrile:distilled water in the ratio of (20:20:60, by volume). The flow rate was 0.8 mL min-1, and UV detection was performed at 230 nm. The HPLC assay was coupled with Environmental Assessment Tool (EAT), which represents a simple and proficient approach for profiling the greenness of the method. This takes into consideration the environmental, health and safety issues for all solvents that involved in the chromatographic method and calculates a total score that can be used for comparison of the greenness of different methods. The method was found to be linear over (0.5-30) µg/mL for all cited drugs with mean percentage recoveries (99.56 ± 1.141) for VTK3, (99.56 ± 1.056) for DVD, (99.62 ± 1.482) for SDS and (99.52 ± 1.205) for SQS. The results were statistically compared with those of the official and reported methods; using Student's t-test and F-test, showing no significant difference with respect to accuracy. Specificity of the applied method was assessed by analyzing the laboratory-prepared mixtures. The developed method was validated according to ICH guidelines. The proposed methodology can be applied for rapid routine assay of this combination.

A Comparative Study Between Conventional ICP-OES and the Innovative PLS Model-Assisted ICP-OES for the Assay of Trace Elements.

BACKGROUND: Inductively coupled plasma is widely used for elemental analysis with the advantage of being eco-friendly since the discharge is free of contaminants. OBJECTIVE: A rapid, novel method was developed for the quantitation of trace elements using inductively coupled plasma with optical emission spectrometry.This method has the advantage of simultaneous calibration compared to the conventional method. METHOD: The assay was carried out for iron, copper, zinc, and molybdenum using the linear regression model partial least-squares. RESULTS: The method was optimized and validated as per the International Conference on Harmonization guidelines, showing highly accurate and precise results. The linearity range was 0.25-4 ppm for all trace elements under investigation. The method was applied for the assay of the cited elements in non-chelated and amino acid chelated multi-mineral preparations in the Egyptian market with acceptable mean percent recovery. CONCLUSIONS: In comparison with the official method by flame emission, statistical analysis showed no significant difference with Student's t-test and F-values. HIGHLIGHTS: Inductively coupled plasma is superior as all of the elements can be measured simultaneously. The method was found to have a high degree of specificity and can be easily applied in routine elemental analysis in laboratories.

Impact Study of Mathematical Manipulation on the Resolution Efficiency of the Spectrophotometric Technique-An Application on Veterinary Binary Mixture with Overlapping Absorption Bands.

BACKGROUND: The impact of mathematical manipulation on the efficiency of smart spectrophotometric approaches was considered for analyzing a veterinary binary mixture of tylosin tartrate (TYT) and doxycycline hydrochloride (DOX). OBJECTIVE: Based on subtraction which can be response subtraction via numerical factor calculation between two wavelengths. METHOD: Absorbance subtraction (AS) and amplitude summation (A-Sum), or subtraction of constant value or spectrum, was used to eliminate the contribution of the interfering component, as is done in spectrum subtraction (SS), extended ratio subtraction (EXRS), ratio subtraction (RS), and derivative subtraction (DS), or multiplication of a constant value by the divisor to get the spectrum of one component, or division by the normalized spectrum to modulate the original absorption spectrum to concentration as in concentration value and also detected in amplitude modulation (AM). The derivative transformation method (DT) is a form of mathematical manipulation that transforms a derivative to its original absorption form. RESULTS: The consumption of these methods will become more significant in quality control departments for the repetitive quantitative analysis of different veterinary products in both research and industry laboratories. Some manipulations may be used for simultaneous analysis of DOX and TYT, such as absorbance subtraction, amplitude modulation, ratio subtraction and derivative subtraction coupled with spectrum subtraction, concentration value, and amplitude summation, while others may be used for DOX only, such as derivative transformation and constant value. CONCLUSIONS: The recovery percentages confirmed that the accuracy and the reproducibility were approved by the following ICH guidelines. HIGHLIGHTS: 1. Partitioning methods: which perfectly divide the drugs response at the iso-point such as amplitude modulation, absorbance subtraction and amplitude summation. 2. Extracting methods: which easily calculate zero-order of the two cited drugs in such as ratio subtraction were coupled with extended ratio subtraction method (RS-EXRS), spectrum subtraction (SS), constant multiplication method (CM) or extract their derivative spectra such as derivative subtraction. 3. Transforming methods: which able to change the derivatized spectrum to its original zero spectra such as derivative transformation. 4. Graphical methods: which directly measure the concentration of the drugs from the chart.

Comprehensive comparative study of eco-friendly Univariate and multivariate methodological approaches on processing multi-component formulation quality.

This study presents comprehensive comparative study of different eco-friendly spectrophotometric approaches without any sample treatment on processing quaternary mixture of sulphadimidine sodium (SDS), sulphaquinoxaline sodium (SQS), diaveridine (DVD) and vitamin K3 (VTK3). The different univariate complementary resolutions according to the response used for the assay of the cited drugs after applying the processing steps were implemented using successive ratio subtraction coupled with constant multiplication (SRS-CM), absorbance subtraction (AS) and amplitude modulation (AM). On the other hand, multivariate spectrophotometric models were developed and validated for simultaneous determination of the cited mixture. Resolution was accomplished by using two multivariate calibration greener models, including principal component regression (PCR) and partial least-squares (PLS). The proposed approaches are considered environmentally friendly since they use only water as reagent, which is cheap and safe for the operator. The calibration graphs are linear over the range of (4.0-13.0) µg/mL for (SDS), (1.0-10.0) µg/mL for (SQS), (1.0-11.0) µg/mL for (DVD) and (1.0-8.0) µg/mL for (VTK3). Specificity of the applied procedures was assessed by analyzing the laboratory-prepared mixtures and their combined dosage form. The outcomes of the developed methods were statistically compared with those of the official and reported methods; using Student's t-test and F-test, showing no significant difference. The proposed methodologies can be used for the routine analysis of the cited drugs in quality control laboratories.

Paired wavelength relevance as spectrophotometric strategy for evaluation the potency of medicine affecting human health.

Paired wavelength relevance as spectrophotometric strategy was carried for simultaneous analysis of unresolved bands of doxycycline hydrochloride (DOX) and tylosin tartrate (TYT) as an example of veterinary binary mixture. These methods based on the relation between two points on the scanned or manipulated spectra (derivative, ratio). The methods using the absorbance difference between two wavelengths namely, dual wavelength (DW), induced dual wavelength (IDW), absorption correction (AC) and advanced absorbance subtraction (AAS) or amplitude difference namely, ratio difference (RD), amplitude subtraction namely, amplitude correction (PC) and advanced amplitude modulation (AAM) as well as amplitude addition namely, derivative ratio (DD1). Calibration graphs are direct relation in the range of (5-40) µg/mL for doxycycline hydrochloride and (5-45) µg/mL for tylosin tartrate. The suggested methods was successfully applied for evaluate the potency of their veterinary medicine that has direct affecting human health. The method has been validated according to the guideline of international conference on Harmonization and parameters like linearity, range, accuracy and precision have been studied. The outcomes were matched statistically with those of the authorized systems; Student's t-test, F-test, and One-way ANOVA, presenting acceptable values and no momentous change with accuracy. The procedures can be considered useful for the quantitative analysis.

A Rare Case of Multiorgan Calciphylaxis in a Patient with Stage 5 Chronic Kidney Disease.

Calciphylaxis or calcific uremic arteriolopathy (CUA) is a potentially life-threatening vasculopathy involving the skin and subcutaneous tissues. It is usually associated with chronic kidney disease (CKD) and rarely with acute renal failure or predialysis patients. The clinical diagnosis of calcific uremic arteriolopathy relies on high index of suspicion. CUA is commonly associated with secondary hyperparathyroidism and high serum calcium and phosphate products. Moreover, using biopsy as a diagnostic tool is controversial, due to the high risk of poor wound healing and sepsis. Radiological studies usually reveal extensive calcification of branching vessels such as penile arteries, eventually leading to gangrene formation in extremities and penis. Histopathological analysis confirms the diagnosis of calcific uremic arteriolopathy and rules out the presence of malignancy. CUA is a systematic disease that involves multiple organs, and to the best of our knowledge this is the first reported case involving the penis, bladder, and eyes.

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.

Kinetic Profiling of the Hydrolytic Reaction of Benazepril: Metabolic Pathway Simulation.

A simple, specific, and rapid kinetic study of benazepril (BNZ) hydrolysis was developed and validated using HPLC. BNZ was degraded using 0.1 N sodium hydroxide at room temperature to produce benazeprilat, which is an active metabolite of BNZ and acts as an angiotensin-converting enzyme inhibitor. Analysis was carried out using an Athena C18 column (4.6 × 250 mm, 5 µm particle size). The mobile phase consists of a mixture of phosphate buffer (pH 4.5) and acetonitrile (53 + 47, v/v) at a flow rate of 1 mL/min. UV detection was accomplished at 242 nm using moexipril as the internal standard. The method was validated according to International Conference on Harmonization guidelines, and the calibration curve was linear over the range 10-100 µg/mL, with acceptable accuracy and precision. Kinetic profiling of the hydrolysis was shown to follow pseudo-first-order kinetics. The method was applied to the assay of BNZ in combined dosage form with no interference from other ingredients. The obtained results were statistically compared with those of the official method, showing no significant difference.

Simultaneous determination of mebeverine hydrochloride and chlordiazepoxide in their binary mixture using novel univariate spectrophotometric methods via different manipulation pathways.

Smart, sensitive, simple and accurate spectrophotometric methods were developed and validated for the quantitative determination of a binary mixture of mebeverine hydrochloride (MVH) and chlordiazepoxide (CDZ) without prior separation steps via different manipulating pathways. These pathways were applied either on zero order absorption spectra namely, absorbance subtraction (AS) or based on the recovered zero order absorption spectra via a decoding technique namely, derivative transformation (DT) or via ratio spectra namely, ratio subtraction (RS) coupled with extended ratio subtraction (EXRS), spectrum subtraction (SS), constant multiplication (CM) and constant value (CV) methods. The manipulation steps applied on the ratio spectra are namely, ratio difference (RD) and amplitude modulation (AM) methods or applying a derivative to these ratio spectra namely, derivative ratio (DD(1)) or second derivative (D(2)). Finally, the pathway based on the ratio spectra of derivative spectra is namely, derivative subtraction (DS). The specificity of the developed methods was investigated by analyzing the laboratory mixtures and was successfully applied for their combined dosage form. The proposed methods were validated according to ICH guidelines. These methods exhibited linearity in the range of 2-28µg/mL for mebeverine hydrochloride and 1-12µg/mL for chlordiazepoxide. The obtained results were statistically compared with those of the official methods using Student t-test, F-test, and one way ANOVA, showing no significant difference with respect to accuracy and precision.

A rapid and sensitive HPLC assay of some concomitant anti-migraine drugs.

This work describes a simple and sensitive method for simultaneous determination of zolmitriptan, naproxen and propranolol in their dosage forms using HPLC. The drugs were separated isocratically on a Zorbax C8 (4.6 × 250 mm with 5 µm particle size) column using a mobile phase composed of 20 mM phosphate citrate buffer [0.1% TEA (pH 3.1)]:methanol:THF (5:3:2, by volumes). The detection was accomplished fluorometrically setting the excitation wavelength at 280 nm and emission wavelength at 360 nm. The method was validated over a linearity range of 100-900 ng/mL for zolmitriptan, 50-300 ng/mL for naproxen and 100-800 ng/mL for propranolol. The assay was successfully applied to the determination of the studied drugs in pharmaceutical dosage forms without interference from tablet excipients with high specificity. The method can be applied successfully in the future for the pharmacokinetic study of these drugs in the human plasma with high accuracy especially that LOQs of zolmitriptan and propranolol in the proposed method cover their Cmax.