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Two chromatographic methods were developed for the simultaneous determination of paracetamol, pamabrom, and pyrilamine maleate in bulk and combined pharmaceutical dosage form. The first method is an ultra-performance liquid chromatographic (UPLC) method, in which separation was carried out by gradient elution using C18 column and a mobile phase composed of solution A (acetonitrile) and solution B (phosphate buffer) (pH 3.5). The elution started with 20% (by volume) acetonitrile ramped up linearly to 100% in 2 min, then kept constant till the end of the run at a flow rate of 1.5 mL min−1 and ultraviolet (UV) detection at 277 nm. The second method depends on the densitometric determination of thin-layer chromatograms of the three drugs. Separation was carried out at 275 nm using chloroform‒acetonitrile (15:35, v/v) as the mobile phase. The proposed methods were validated according to the International Conference on Harmonisation (ICH) guidelines. Beer’s law was obeyed in the range of 5–100 μg mL−1 for paracetamol and 0.5–20 μg mL−1 for pamabrom and pyrilamine maleate, respectively, with mean recoveries of 98.40‒100.32% ± 0.551‒0.771 for the UPLC method. Linearity of the thin-layer chromatographic method was achieved in the range of 10‒280, 5‒45, and 1–20 ng per spot of the three drugs with mean recoveries of 98.75‒100.30% ± 0.971‒1.061, respectively. The two methods were successfully applied for the simultaneous determination of the cited drugs in their laboratory-prepared mixtures and pharmaceutical dosage form with good accuracy and precision. The results obtained were compared with those of the reported method and found to be in good agreement.
The aim of this study was to compare the antioxidant activity of crude extracts of differing polarities of the fruits of Chaenomeles speciosa (Sweet) Nakai. The antioxidant compositions of the extracts were analyzed qualitatively and quantitatively, respectively. The 75% ethanol extract of the dried fruits was fractionated by sequential extraction using petroleum ether, ethyl acetate, and n-butyl alcohol. The antioxidant effectiveness of the components of differing polarities was examined by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging method and compared with two reference substances: ascorbic acid and butylated hydroxytoluene (BHT). The total phenolic content of the extracts was analyzed using the Folin–Ciocalteu method and expressed as gallic acid equivalents. The active compounds were analyzed by thin-layer chromatography (TLC)–bioautography and ultra-performance liquid chromatography (UPLC). The order of antioxidant capacities of various solvent extracts from the fruit of C. speciosa was found to be ethyl acetate ≥ n-butyl alcohol > petroleum ether. The ethyl acetate extract was more active than the reference substances ascorbic acid and BHT. The radical-scavenging capacity of the extracts decreased as the total phenolic content decreased. TLC–bioautography revealed that the ethyl acetate extract contained many antioxidant spots that can remove DPPH radical, and protocatechuic acid and chlorogenic acid were the major antioxidant components. UPLC analysis confirmed that protocatechuic acid and chlorogenic acid were mainly distributed in the ethyl acetate fraction. The study demonstrated that the ethyl acetate extract had excellent antioxidant capacity. The total phenolic, protocatechuic acid, and chlorogenic acid contents of this extract were higher than those of the other two solvent extracts. These results showed that the ethyl acetate extract from the fruit of C. speciosa could be considered as a potential source of natural antioxidant agent.
Phenolic contents, antioxidant and antimicrobial activities were determined by two samples from summer (June) and winter (December) seasons of Ligularia fischeri var. spiciformis Nakai. A total of 24 phenolic compounds were identified by ultra-performance liquid chromatography (UPLC) analysis. Myricetin (1964.35 and 1829.12 μg/g) was the most dominant flavonol compared to quercetin and kaempferol. Salicylic acid (222.80 and 215.25 μg/g) was the most important phenolic compound compared to pyrogallol, caffeic acid, gentisic acid, o-coumaric acid, gallic acid, protocatechuic acid and ferulic acid in summer (June) and winter (December) seasons. Phenolic contents and antioxidant capacities were estimated for the various solvent extracts (petroleum ether, butanol, ethyl acetate, methanol and water). Ethyl acetate extract exhibited the highest phenolic (332.64 and 299.44 mg/g gallic acid equivalent) and flavonoid contents (5.72 and 5.29 mg/g quercetin equivalent) and also the strongest antioxidant activity in summer and winter seasons. Due to these metabolic variations, the antioxidant and antimicrobial activities were increased with summer seasons compared to winter seasons. Our study shows that the samples collected in June had higher phenolic compounds, stronger antioxidative and antimicrobial activity than the samples of L. fischeri leaf extracts collected in December.
A simple, selective, and sensitive thin-layer chromatographic—densitometric method has been developed for the determination of sulfasalazine besides its possible impurities in pharmaceutical preparations. The mobile phase was composed of ethyl acetate—methanol—ammonia 25% 10:7:3 (υ/υ/υ), and the stationary phase was aluminum plates precoated with silica gel 60 F254 that enabled to obtain well resolved peaks of sulfasalazine and its impurities. The developed chromatograms were analyzed densitometrically at λ = 360 nm. R F values and ultraviolet (UV) spectra were used to identify the compounds. The developed method is highly sensitive (limit of detection [LOD] = 17.11 ng spot−1, limit of quantitation [LOQ] = 51.84 ng spot−1), precise (relative standard deviation [RSD] = 1.43%–4.28%), and accurate (RSD = 1.64%–4.27%). The linearity of the method was checked within the range 20–120 ng spot−1. The method was successfully applied for the determination of sulfasalazine in pharmaceutical preparations besides its impurities. The structures of impurities present in the standard substance and in pharmaceutical preparations were established by ultra-performance liquid chromatography—tandem mass spectrometry (UPLC—MS/MS) technique.
. [17]. M. Swartz , HPLC to UPLC method migration, An overview of key considerations and available tools, 2007 Waters Corporation , http://wwwwaterscom/webassets/cms/library/docs/720002064enpdf
] A. Vijaya Bhaskar , N. Reddy , G. Venugopal , G. Reddy , V. Madhavi , A selective and sensitive UPLC-MS/MS approach for trace level quantification of four potential genotoxic impurities in zolmitriptan drug
sensitivity and selectivity of these analyses, new methodologies (e.g., LC coupled with MS and tandem MS) have been developed [ 12 , 13 ]. In the present study, an ultra-performance liquid chromatography (UPLC)–tandem MS (MS/MS) was applied to study the
, hydrochlorothiazide and all known related compounds when in the finished product dosage form using HPLC and UPLC , University of North Carolina , Wilmington, NC , 2011 . [14] S
include Liquid Chromatography Tandem Mass Spectroscopy (LC-MS), Ultra-Performance Liquid Chromatography (UPLC). There are numerous articles that suggest how to find out amount of HCTZ in plasma, urine, and serum. Antihypertensive patients can benefit from
