Investigating the stability of a cerebral vasodilator drug using chromatographic methods: Evaluation of methods' practicality and environmental aspects.

A vinca alkaloid; vinburnine (VNB) is utilized as an effective vasodilator. As a cyclic amide-containing drug, it is likely susceptible to hydrolytic degradation. This study examined the degradation profile of VNB, findings indicated that VNB undergoes degradation solely in the presence of alkali, generating a carboxylic acid derivative (DEG).

Green Chromatographic Assay of Toxic Impurities of Cyproheptadine: In Silico Toxicity Profiling.

Cyproheptadine (CYP) is an antihistaminic and anti-serotonin drug used to improve the clinical course of hospitalized patients severely affected by COVID-19 and requiring supplemental oxygen. Thin layer chromatography (TLC)-densitometry method was developed and validated for the estimation of CYP and its impurity, dibenzosuberone and its degradation product: 10, 11-dihydroxy-dibenzosuberone. The toxicity profiles of CYP impurity and degradation product were studied and the in silico data, using pre-ADMET software, proved their toxicity.

Ecofriendly HPLC Method for Simultaneous Determination of the Co-Prescribed Drugs in Chemotherapy Omeprazole, Ondansetron and Deflazacort in Spiked Human Plasma.

Green, selective and accurate high-performance liquid chromatography (HPLC) chromatographic method is presented for simultaneous separation and quantitation of the co-prescribed drugs in chemotherapy omeprazole, ondansetron and deflazacort in spiked human plasma. An isocratic HPLC separation was performed on X Bridge C18 (4.6 × 250 mm) column with 5 μm particle size using mobile phase consisting of methanol: ammonium acetate buffer pH 4 adjusted by acetic acid (60: 40, v/v).

Ecofriendly Chromatographic Assay of Metformin Combinations; Content Uniformity Tests and Toxicity Profiling.

Accurate, sensitive and green HPTLC chromatographic method was proposed for simultaneous determination of metformin, glipizide and sitagliptin in the presence of metformin potential toxic impurities melamine and cyanoguanidine. The separation was completed on silica gel HPTLC F254 plates using a mixture of ethyl acetate: methanol: ammonia: formic acid (7: 2: 0.2: 0.

Ecofriendly appraisal of stability-indicating high-performance chromatographic assay of canagliflozin and metformin with their toxic impurities; in silico toxicity prediction.

Canagliflozin is an oral hypoglycemic drug recently formulated in combination with a biguanide, metformin hydrochloride, for improving its hypoglycemic action. Canagliflozin has one reported major degradation product, also metformin hydrochloride has one reported major degradation product, cyanoguanidine, and has a potential toxic impurity, melamine, that is reported to cause crystalluria that causes chronic kidney inflammation and nephrolithiasis leading to a renal failure. As per International Conference of Harmonization guidelines; a drug degradation product is classified as a type of drug impurities.

Sensitive and selective bioscreening of the most commonly used coronavirus disease drug, Favipiravir, and its co-administered therapeutic, Meropenem, in human plasma.

Favipiravir and Meropenem have been concurrently used as directly acting antiviral and antibiotic agents for the treatment of coronavirus disease in human plasma. Accurate and specific reversed phase ultra-performance liquid chromatographic and high-performance thin-layer chromatographic methods were developed and validated for the first time analysis of this combination in spiked human plasma using Cefepime as an internal standard. In the developed ultra-high-performance liquid chromatography method, separation was performed on a BEH C18 column with a mixture of ACN and 0.

Rapid and ecofriendly UPLC quantification of Remdesivir, Favipiravir and Dexamethasone for accurate therapeutic drug monitoring in Covid-19 Patient's plasma.

Innovative therapeutic protocols to the rapidly spreading coronavirus disease (COVID19) epidemic is highly required all across the world. As demonstrated by clinical studies, Favipiravir (FVP) and Remdesivir (REM) are new antiviral medicines that are effective against COVID-19. REM is the first FDA approved antiviral medicine against COVID-19.

Validated spectral manipulations for determination of an anti-neoplastic drug and its related impurities including its hazardous degradation product.

Innovative and specific double dual wavelength, dual ratio subtraction spectrophotometric methods were carried out along with a successive ratio subtraction spectrophotometric method for determination of dacarbazine and its related impurities including toxic and hazardous ones. For determination of dacarbazine by the double dual wavelength method, the absorbance differences between 323 and 350 nm of the zero order absorption spectra of dacarbazine were used. The values of absorbance difference between 267.

Spectrophotometric Determination of Metformin in Different Pharmaceutical Combinations With Glipizide or Sitagliptin in Presence of Toxic Impurities of Metformin.

Background: The presented quadruple divisor spectrophotometric method was able to resolve and analyze a complex quintuple drug matrix with severe overlapped spectra without previous separation or extraction steps or need of complicated apparatus like chromatographic methods and had the advantage of being green as the solvent used was water.

Method: A simple, sensitive, and precise quadruple devisor spectrophotometric method was developed for simultaneous determination of metformin, glipizide, and sitagliptin in the presence of metformin potential impurities melamine and cyanoguanidine. The proposed method was applied for analysis of metformin, glipizide, and sitagliptin in pure form and pharmaceutical formulation (tablets).

Development and Validation of Two Chromatographic Methods for Simultaneous Determination and Quantification of Amiloride Hydrochloride, Hydrochlorothiazide, and Their Related Substances, in Pure and Tablet Forms.

Background: Amiloride hydrochloride (AM) is a potassium sparing diuretic, while hydrochlorothiazide (HCZ) is the protype of thiazide diuretics. The combining of the studied drugs exhibits a synergistic effect. Moreover, HCZ prevents the potassium depletion side effect caused by AM.

Development and Validation of RP-HPLC and an Ecofriendly HPTLC Method for Simultaneous Determination of Felodipine and Metoprolol Succinate, and their Major Metabolites in Human Spiked Plasma.

Background: Felodipine is a calcium channel blocker used together with metoprolol succinate for treatment of hypertension.

Objective: Two chromatographic methods were developed for simultaneous determination of felodipine (FEL) and metoprolol succinate (MET), and their major metabolites, dehydrofelodipine and metoprolol acid, respectively.

Methods: The first method was RP-HPLC which comprised separation of the studied components by gradient elution using a Phenomenex C8 column and a mobile phase composed of water (adjusted to pH 3.

Evaluation of vinburnine in pharmaceuticals by smart spectrophotometric methods; full stability study.

Vinburnine (VNB) is a vinca alkaloid used as a vasodilator to enhance cerebral circulatory insufficiency. It is a cyclic amide containing drug which is expected to be sensitive to hydrolytic degradation. The degradation profile of VNB was studied in this work following ICH recommendations for stability study.

Chromatographic determination of sulfasalazine and its active metabolites: greenness assessment and application to spiked human plasma.

Green TLC-densitometric and RP-HPLC methods were developed and validated for the determination of the active prodrug sulfasalazine (SZ), its active metabolite mesalazine (MZ) and the major active metabolite of mesalazine, N-acetyl-5-aminosalicylic acid (AS). In the developed TLC-densitometric method, chromatographic separation was carried out on TLC silica gel plates 60 F using a developing system consisting of ethyl acetate-methanol-ammonia solution 33% (8:2.5:0.

Development and Validation of HPTLC and Green HPLC Methods for Determination of a New Combination of Quinfamide and Mebendazole.

Two selective and sensitive chromatographic methods were developed for simultaneous determination of new combination of quinfamide and mebendazole in bulk powder and in pharmaceutical formulation. The first method is HPTLC by which separation was obtained using silica gel HPTLC F254 plates and a simple mobile phase consisting of methanol:toluene (2:6, v/v) and the separated bands were scanned at 254 nm. The second method RP-HPLC that comprised isocratic separation of both drugs on a Phenomenex C18 column using a green mobile phase consisting of double distilled water:methanol (30:70, v/v) at a flow rate of 0.

Green Simultaneous Chromatographic Separation of Pyridostigmine Bromide and Its Related Substances in Pure Form, Tablets and Spiked Human Plasma.

A green, accurate and specific high-performance thin-layer chromatographic (HPTLC) method was developed and validated for simultaneous quantitative determination of pyridostigmine bromide (PR), impurity B (IMP B);3-hydroxy-N-methylpyridinium bromide and impurity A (IMP A); pyridin-3-yl-dimethylcarbamate. The two pharmacopeial impurities are also its main inactive metabolites. Furthermore, IMP B is known to be its alkaline-induced degradation product.

Stability-indicating chromatographic and chemometric methods for environmentally benign determination of canagliflozin and its major degradation product; A comparative study and greenness assessment.

Recently, concepts of sustainable developments, like considering the environmental effect of chemicals used and the amount of hazardous wastes produced, has gained much interest. In this work, a recently approved treatment for type II diabetes mellitus, canagliflozin, was quantified along with its degradation product by two eco-friendly methods. The first was a specific green HPLC method using a C column as a stationary phase and a mobile phase consisting of methanol-water (98:2, v/v) pumped at a flow rate of 1 mL/min with UV detection at 225 nm, and using ibuprofen as an internal standard.

Novel manipulations of ratio spectra as powerful tools for resolution and quantitative determination of Pyridostigmine bromide and its' related substances; A comparative study.

Resolution and quantitative determination of ternary mixture with severely overlapped spectra without any preliminary separation steps represents a big challenge for any analyst. Smart and novel spectrophotometric methods are continuously innovated for achieving the above mentioned target. Novel applications of ratio difference spectrophotometric technique utilizing ratio spectra and derivative ratio spectra are applied in presented work.

Development and validation of HPTLC and green HPLC methods for determination of furosemide, spironolactone and canrenone, in pure forms, tablets and spiked human plasma.

Two selective and accurate chromatographic methods are presented for simultaneous quantitation of spironolactone (SP) and furosemide (FR) and canrenone (CN), the main degradation product and the main active metabolite of SP. Method A was HPTLC, where separation was completed on silica gel HPTLC F plates using ethyl acetate-triethylamine-acetic acid (9:0.7:0.

Successive ratio subtraction as a novel manipulation of ratio spectra for quantitative determination of a mixture of furosemide, spironolactone and canrenone.

Furosemide and spironolactone are commonly prescribed antihypertensive drugs. Canrenone is the main degradation product and main metabolite of spironolactone. Ratio subtraction and extended ratio subtraction spectrophotometric methods were previously applied for quantitation of only binary mixtures.

Canagliflozin stability study and ecofriendly chromatographic determination of its degradation product: A comparative study.

Canagliflozin is a newly approved drug for type II diabetes mellitus. A full stability study of canagliflozin was performed following international conference on harmonization strategies. The drug was stable against all conditions except oxidation where only one degradation product was separated and structurally elucidated using mass spectrometry and infrared spectroscopy.

A comparative study of ICH validated novel spectrophotometric techniques for resolving completely overlapping spectra of quaternary mixtures.

A pharmaceutically marketed mixture of Yohimbine, Alpha-tocopheryl acetate, Niacin, and Caffeine co-formulated as a promising therapy for erectile dysfunction. Simultaneous determination of the aforementioned pharmaceutical formulation without prior separation steps was applied using mean centering of ratio spectra and triple divisor spectrophotometric methods. Mean centering of ratio spectra method depended on using the mean centered ratio spectra in three successive steps which eliminated the derivative steps and so the signal to noise ratio was improved.

Validated RP-HPLC and TLC-Densitometric Methods for Analysis of Ternary Mixture of Cetylpyridinium Chloride, Chlorocresol and Lidocaine in Oral Antiseptic Formulation.

This work was concerned with development, optimization, application and validation of reversed phase high performance liquid chromatography (RP-HPLC) and thin layer chromatography (TLC)-densitometric methods for analysis of cetylpyridinium chloride, chlorocresol and lidocaine in Canyon(®) gel. The first developed RP-HPLC method depended on chromatographic separation on a ZORBAX Eclipse Plus C8 column, with elution with a mobile phase consisting of 0.05% phosphoric acid solution : acetonitrile : methanol (15 : 24 : 61, by volume), pumping the mobile phase at a flow rate of 1.