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EN
A novel quantitative method for the determination of quizalofop-p-ethyl herbicide has been developed and validated using high-performance liquid chromatography with ultraviolet detection (HPLC-UV), which is cost-effective, easy to use, and rapid. This active ingredient is widely used as a systemic herbicide belonging to the aryloxy phenoxy-propionates group and is the active component in Torgy 5% EC® product, a formulation specifically designed for controlling unwanted weeds in various crops. The mobile phase is composed of a gradient of miscible solvents (acetonitrile and distilled water) in the 4:1 (v/v) ratio at a flow rate of 1.5 ml/min with UV detection at 260 nm. The reversed-phase brownlee™ C-18 column that was thermostated at 30°C used for quantification. The method's validation procedures, such as selectivity, linearity, range, LOD, LOQ, and trueness (bias and recovery), were discussed according to ICH guidance standards. The validation results demonstrated that this innovative method is suitable for assessing the content of quizalofop-p-ethyl within the 2-10 mg/mL range. The high value of the regression coefficient (R²=0.9971) underscores that the method is fit-for use for analytical applications.
EN
In the quest for sustainable water purification methods, electrochemical Advanced Oxidation Processes (AOPs) emerge as pivotal strategies against organic pollutants. This study delves into the efficacy of the Electro-Fenton process, a distinguished AOP that leverages the in-situ generation of hydroxyl radicals (•OH) via the electrochemical reduction of oxygen. By conducting systematic experiments in deionized water, we evaluate the influence of catalyst concentration, applied current density, and cathode material selection on the degradation kinetics of marbofloxacin – a model pharmaceutical pollutant. Employing advanced statistical and kinetic modeling, our investigation reveals critical insights into the process dynamics, uncovering the nuanced interplay between operational parameters and degradation efficiency. The findings substantiate the Electro-Fenton process as an environmentally advantageous and effective solution for water decontamination and advancing the field of water purification technology.
EN
The present study appraised the inhibitory role of ethanol (PDEE) and ethyl acetate (PDEAE) extracts of Phoenix dactylifera L. against three molecularly identified fungi: Fusarium oxysporum, Botrytis cinerea, and Rhizoctonia solani. HPLC analysis revealed that gallic acid was the major phenolic compound in both extracts: (PDEE: 1721.90 μg/g) and (PDEAE: 101.53 μg/g). The major flavonoids in PDEE are rutin, kaempferol, and quercetin, whereas PDEAE contains kaempferol, naringenin, and quercetin. The GC-MS showed 11-octadecenoic acid methyl ester (26.25%) is the highest compound in PDEE, while diisooctyl phthalate (18.82%) is the most important compound in PDEAE. At 50 μg/mL, the inhibition percentage of PDEAE initiated the highest growth inhibition of F. oxysporum (49.63%) and R. solani (71.43%). Meanwhile, PDEE at 200 μg/mL initiated an inhibition value of 77.78% for B. cinerea. As a result, PDEAE is considered more effective than PDEE in controlling the growth of selected isolates.
EN
Based on chromatographic fingerprinting combined with quantitative analysis on characteristic chemical constituents as well as hierarchical cluster analysis, an easy and sensitive approach utilizing high performance liquid chromatography (HPLC) was developed for the identification and quality evaluation of Rutongshu oral liquid (ROL). What is more, nontargeted metabolomic analysis was conducted to gain a global view in terms of its chemical profile. In this study, 16 peaks from different batches (S1-S10) of ROL samples produced by Taihe Hospital of Chinese Medicine were selected as common peaks for the evaluation of their similarity whose values of all tested 10 batches exceeded 0.90 when compared with the control fingerprints. Meanwhile, simultaneous quantification of five markers in the oral solution, including albiflorin, paeoniflorin, chlorogenic acid, quercetin and ferulic acid was performed, and standard curves established for respective reference substances showed good regression in the linear range (r2> 0.999) with recoveries in the range of 98.96-102.35%. The ultra-high performance liquid chromatography (UHPLC) combined with Orbitrap Exploris 120 mass spectrometer resulted in 88 identified compounds. The results of validation showed that the established method was reproducible, precise and stable. This study offers an effective, dependable and useful approach for the systematic evaluation of the hospital formulation ROL.
EN
Pinus merkusii Jungh & De Vries. has become increasingly gathered more attention from researchers because the plant has a range of folk medicinal uses. Heartwood plant is the major source of dehydroabietic acid (DHAA) and abietic acid (AA), which possesses several medicinal properties, such as antiviral, antimicrobial, antiobesity and anti-inflammatory. The research proposed herein a low-cost, fast, specific, uncomplicated, sensitive, precise reverse-phase high-performance liquid chromatography (RP-HPLC). This method was conducted and validated for evaluating an amount of DHAA and AA in ethanol extract and oral spray containing P. merkusii heartwood extract. Additionally, stability and antimicrobial activities against clinically isolated Streptococcus mutans of the oral spray were determined. The separation was achieved on Pursuit 200Å PFP column, 150 3 4.6 mm, particles of 3 μm with a flow rate of 1.0 mL min-1. Methanol and water (70:30 v/v) were used as eluent with an isocratic mode and sample analysis volume was set at 10 μL, at a detection wavelength of 210 and 245 nm. The developed HPLC method for analysis of DHAA and AA showed good linearity with correlation coefficients equal to 1. Moreover, other validation parameters, comprised of accuracy, precision, specificity and detection and quantitation limits of this method displayed excellent reliability, validity and sensitivity. This method could be an interesting alternative for quantitative measurement of P. merkusii heartwood extract, oral spray formulation and other P. merkusii heartwood extract preparations. The result from antibacterial tests suggested that the oral spray containing P. merkusii heartwood extract is able to inhibit the oral pathogens causing dental caries. The oral spray decreased S. mutans population size by about 0.5–2 Log CFU mL-1 at 1–4 h and complete elimination of all bacteria strains within 24 h. This study provides validity for using P. merkusii heartwood extract as an alternative for preventing and treating oral infectious diseases.
EN
The study was aimed to validate and optimize high performance liquid chromatographic (HPLC) method for the determination of coumarin-3-carboxylic acid (C3A) in the heart and liver issue of Sprague-Dawley (SD) rats after intragastric administration of extractive of leaves of Ficus virens var sublanceolata. And simple ADME and target prediction analyses were performed for C3A. Ethyl acetate was employed to precipitate protein with appropriate sensitivity and acceptable matrix effects. The satisfactory separation was developed on an ODS2 column (4.6 mm × 250 mm, 5 μm) by gradient elution with a methanol-acetic acid solution (pH = 3.0) as the mobile phase. The flow rate was 1.0 mL min⁻¹, the column temperature was maintained at 30 ± 2 °C, the injection volume was 20 μL, and the detection wavelength was set as 309 nm. The method was fully validated in terms of selectivity, linearity, accuracy, precision, extraction recovery and stability. The results of the ADME analysis found that C3A has excellent characteristics of drug-likeness, consistent with good bio-absorption. And the predicted 12 target protein belongs to the amine oxidoreductase and carbonic anhydrase target class. This method is simple, rapid, sensitive, and accurate for the determination of coumarin-3-carboxylic acid in the heart and liver tissue of SD rats.
EN
The retention behaviour of scopolamine (hyoscine) and its related compounds (norhyoscine, atropine, homatropine, and noratropine) was investigated on the silica-based HPLC stationary phase. The retention of investigated tropane alkaloids was interpreted by using the Soczewinski-Wachtmeister equation. A high correlation between the retention parameter (log k) and lipophilicity (log P) (R 5 0.9923) confirms the significant influence of hydrophobic interactions on the retention behaviour of the aforementioned compounds. It was found that by increasing the acetonitrile fraction, a decrease in retention of the more polar epoxide derivatives (scopolamine, norhyoscine) and an increase in retention of the more lipophilic derivatives (atropine, noratropine, homatropine) is obtained. The best separation of the tropane alkaloids was achieved by a simple procedure that involved a mobile phase composed of acetonitrile and 40mM ammonium acetate/0.05% TEA, pH 6.5; 50:50 v/v. Selected conditions were assumed for the determination of scopolamine hydrochloride in the eye drops (Scopolamini hydrobromidum 0.25%). The method was validated and it was found as selective, sensitive, precise, accurate, and robust for the further qualitative analysis of the scopolamine-related compounds.
EN
Mirtazapine is an antidepressant medication used to treat the major depressive disorder in adults. In this study, two different chromatographic methods were developed for the determination of mirtazapine in pharmaceutical products. In the first method, An Extend C18 column (250 3 4.6 mm, 5 μm) was used and the temperature was kept constant at 25°C. The mobile phase was determined as 0.1% formic acid solution and acetonitrile (80/20, v/v), and isocratic elution was applied. The flow rate of the mobile phase was determined as 1.0 mL min-1 and the injection volume was 20 μL. Detection was performed at 291 nm. using a UV detector. In the second method, ethanol was used as the organic modifier. The only difference between these methods was the organic modifier. All other conditions of the methods were the same. Both chromatographic methods were validated by ICH guidelines for various parameters such as selectivity, linearity, accuracy, precision, detection and quantification limit, and robustness. The determination coefficients of chromatographic methods were greater than 0.999 in the concentration range of 5–30 μgmL-1. of mirtazapine. Later, these chromatographic methods were applied to pharmaceutical formulations. Comparison of the obtained results in terms of means was made using Student’s (t) test, and comparisons in terms of standard deviations were made using the Fischer (F) test. It was observed that there was no significant difference between these methods. These two methods were then evaluated using the AGREE-Analytical GREEnness metric software. The chromatographic method using ethanol as an organic modifier has been proposed as an excellent eco-friendly and analyst-friendly alternative for the determination of mirtazapine in pharmaceutical formulations.
PL
W XXI wieku, różne wydarzenia polityczne i społeczne powodują pojawianie się nowych zagrożeń związanych z produkcją, przechowywaniem i użyciem środków bojowych zawierających kruszące materiały wybuchowe. Zanieczyszczenia stanowią wyzwanie dla specjalistycznych laboratoriów, które zajmują się ich wykrywaniem i identyfikowaniem źródła pochodzenia. Niestety, tego typu zanieczyszczenia mają poważny wpływ na ludzkie zdrowie powodując m.in. poważne uszkodzenia układów i narządów człowieka, a także długotrwałe skutki zdrowotne, takie jak choroby nowotworowe i inne poważne zaburzenia zdrowia. Dlatego ważne jest, aby zwrócić uwagę na te zagrożenia i zrobić wszystko, co w naszej mocy, aby zapobiegać ich pojawianiu się i zminimalizować ich szkodliwe skutki. W badaniach ekosystemów częstym problemem jest niskie stężenie badanej substancji, które jest poniżej limitu detekcji urządzenia. W takich przypadkach biowskaźniki kumulacji okazują się być bardzo pomocne. Biomarkery są doskonałym narzędziem do wykrywania zanieczyszczeń w wodzie płynącej i w glebie Dzięki nim można stwierdzić obecność określonych czynników chemicznych, a jednocześnie są one czułym wskaźnikiem reakcji ekosystemu na skażenie. W oparciu o chromatografię cieczową została opracowana uniwersalna metoda, która umożliwia analizę trotylu i jego pochodnych w wytypowanym przez nas biowskaźniku akumulacji - larwach chruścików z gatunku Hydropsyche angu-stipennis, Curtis 1834 oraz próbkach gleby, czy innych złożonych matrycach. Metoda chromatograficzna pozwala na ilościowe i jakościowe oznaczenie różnych pochodnych trotylu, takich jak 2,6-diamino-4-nitrotoluen, 2,4-dia-mino-6-nitroto-luen, 1,3,5-trinitrobenzen, trójnitrotoluen, 2-amino-4,6-dinitrotoluen, 4-amino-2,6-dinitrotoluen i tetrylu w złożonej matrycy biologicznej. Dodatkowo prze-prowadzono badanie efektu kumulacji trotylu w tkance larw chruścików poddanych ekspozycji w rozworach testowych zwierających trotyl przez 1 do 24 godzin. Zauważono efekt wysycenia oraz zmierzono stężenie pochodnych trotylu. Zaobserwowane efekty potwierdziły użyteczność wytypowanej larwy jako biowskaźnika akumulacji zanieczyszczeń trotylu w ekosystemie.
EN
Different political and social events of the 21th century have been bringing about the appearance of new threats connected with production, storing and using of combat assets containing the high explosive materials. The contaminations are challenging for specialised laboratories dealing with their detection and identification of sources of origin. Unfortunately, such contaminations have a serious influence into the human health causing for instance significant injuries of human systems and organs, and long term problems with the health such as cancer diseases and other serious health disturbances. Therefore, it is important to focus attention on these threats, and to do everything possible to prevent their appearance and minimise the harmful effects. A low concentration of tested agent, below the instrument detection threshold, is a frequent problem at investigations of ecosystems. In such cases biomarkers of cumulation prove to be very helpful. Biomarkers can be a perfect tool for detection of contaminations in the flowing water and in the ground. They can be used to establish the presence of specific chemical agents and at the same time they are a sensitive indicator of eco-system’s reaction to the contamination. A universal method was developed basing on the liquid chromatography for analysis of trotyl and its derivatives present in larvae of caddisflies from species of Hydropsyche angustipennis, Curtis 1834, and in the samples of soil, or in other complex matrixes. The chromatographic method can label quantitively and qualitatively different derivatives of trotyl, such as 2,6-diamino-4-nitrotoluene, 2,4-dia-mino-6-nitrotoluene, 1,3,5-trinitrobenzen, trinitrotoluene, 2-amino-4,6-dinitrotoluen, 4-amino-2,6-dinitrotoluen, and tetryl in a complex biologic matrix. Additionally, an effect was investigated of trotyl cumulation within 1 to 24 hours in the tissue of cad-disfly larvae subjected to exposition of tested solutions contained trotyl. An effect of saturation was noticed and the concentration of trotyl derivatives was measured. Observed effects con-firmed the usefulness of chosen larvae as a bio-indicator of trotyl contamination accumulation in ecosystem.
EN
Threats associated with the production, storage and use of warfare agents containing high explosives against the backdrop of political and social events emerging in the 21st century present new challenges for specialized laboratories involved in detecting contamination and identifying its source. A common analytical problem in studies conducted in the ecosystem is the low concentration of the test substance - below the detection limit of the instrument. Helpful in solving this dilemma are accumulation bio-markers, which appear to be an excellent tool for detecting contamination in, for example, flowing water. Such biomarkers make it possible to determine the presence of specific chemical agents at the same time they are a sensitive indicator of the ecosystem's response to contamination. The presented chromatographic method allows quantitative and qualitative determination of 2,6-diamino-4-nitrotoluene, 2,4-diamino-6- nitrotoluene, 1,3,5-trinitrobenzene, trinitrotoluene, 2-amino-4,6-dinitrotoluene, 4-amino-2,6- dinitrotoluene and tetryl in the biological matrix. The effects of accumulation in the tissue of crustaceans on TNT test solutions were studied from 1 to 24 hours. The saturation effect was observed and the concentration of TNT derivatives was measured. The observed effects confirmed the usefulness of the selected larva as a bio-indicator of TNT contaminant accumulation in the ecosystem.
PL
agrożenia związane z produkcją, przechowywaniem oraz użyciem środków bojowych zawierających kruszące materiały wybuchowe na tle wydarzeń politycznych i społecznych pojawiających się w XXI wieku stanowią nowe wyzwania dla specjalizowanych laboratoriów zajmujących się wykrywaniem skażeń oraz identyfikowaniem źródła jego pochodzenia. Częstym problemem analitycznym w badaniach prowadzonych w ekosystemie jest niskie stężenie badanej substancji – poniżej limitu detekcji urządzenia. Pomocne w rozwiązaniu tego dylematu są biowskaźnik kumulacji, które wydają się doskonałym narzędziem do wykrywania zanieczyszczeń np. wody płynącej. Biomarkery takie umożliwiają stwierdzenie obecności określonych czynników chemicznych jednocześnie są czułym wskaźnikiem reakcji ekosystemu na skażenie. Przedstawiona metoda chromatograficzna pozwala ilościowo i jakościowo oznaczyć 2,6-diamino-4-nitrotoluen, 2,4-diamino-6-nitrotoluen, 1,3,5-trinitrobenzen, trinitrotoluen, 2-amino-4,6-dinitrotoluen, 4-amino-2,6-dinitrotoluen oraz tetryl w matrycy biologicznej. Badano efekty kumulacji w tkance chruścików na roztworach testowych trotylu w czasie od 1 do 24h. Zaobserwowano efekt wysycenia oraz zmierzono stężenie pochodnych trotylu. Zaobserwowane efekty potwierdziły użyteczność wytypowanej larwy jako biowskaźnika akumulacji zanieczyszczeń trotylu w ekosystemie. Zaobserwowane efekty potwierdziły użyteczność wytypowanej larwy jako biowskaźnika akumulacji zanieczyszczeń trotylu w ekosystemie.
EN
The study investigated the stability of nitrocellulose (NC) powders modified with nitroglycerine (NG) and/or polyos 250 (polyester polyol) or centralite I (CI) and determined the changes in physicochemical properties before and after accelerated ageing. Six NC modified powders stabilized with diphenylamine (DPA) or CI were tested. Accelerated ageing of the powders was carried out in accordance with AOP-48, under isothermal heating at 71 °C for 35 days, which corresponds to storing the powders at 25 °C for 10 years. The initial powder samples and those aged under the above conditions were examined by high-performance liquid chromatography (HPLC) for loss of initial stabilizer (DPA or CI), calorimetry, and manometric bomb. The geometric changes of gunpowder grains and their densities, were also compared before and after accelerated ageing. Tests on the stability of the powders by means of heat flow microcalorimetry (HFC) conducted in accordance with STANAG 4582 at 90 °C for 3.43 days, showed that the tested powders did not exceed the permissible limit of a released heat power of 350 μW/g, which means that they should be stable for the next 10 years of storage at 25 °C. This diagnosis was confirmed by chromatographic (HPLC) analyses of stabilizer loss. After accelerated ageing, the content of modifiers and stabilizers was lower compared to the initial powders. Ageing at elevated temperatures did not change the geometry of the aged powders relative to the starting powders. For most of the tested powders, accelerated ageing resulted in a slight increase in calorific value relative to the starting powders. Comparable helium density values were obtained for the powders before and after ageing, all of which were within error limits. Accelerated ageing did not significantly affect the changes in dynamic vivacity between the aged and initial powders. The tested NC modified powders should not change their properties enough during 10 years of storage at 25 °C to become unstable, i.e. unsafe when stored and/or to fail to meet ballistic requirements.
PL
Celem pracy było badanie stabilności nitrocelulozowych (NC) prochów modyfikowanych nitrogliceryną i/lub poliosem 250 (poliolem poliestrowym) albo centralitem I (CI) oraz określenie zmian właściwości fizykochemicznych przed i po przyspieszonym starzeniu. Badaniom poddano 6 NC prochów modyfikowanych stabilizowanych difenyloaminą (DFA) lub CI. Sztuczne starzenie prochów przeprowadzono według normy AOP-48, w ramach izotermicznego ogrzewania w 71 °C przez 35 dni, co odpowiada przechowywaniu prochów w temperaturze 25 °C przez 10 lat. Wyjściowe próbki prochów oraz starzone w ww. warunkach badane były za pomocą wysokosprawnej chromatografii cieczowej (HPLC) pod kątem ubytków stabilizatora wyjściowego (DFA albo CI), kalorymetrii, bomby manometrycznej. Porównano również przed i po przyspieszonym starzeniu zmiany geometryczne ziaren prochowych i ich gęstości. Badania stałości prochów za pomocą mikrokalorymetrii przepływowej (HFC) prowadzone według STANAG-u 4582 w temp. 90 °C przez 3,43 doby wykazały, że badane prochy nie przekroczyły dopuszczalnego limitu wydzielonej mocy cieplnej wynoszącego 350 μW/g, co oznacza, że powinny być stabilne przez następne 10 lat przechowywania w temperaturze 25 °C. Diagnozę tę potwierdziły analizy chromatograficzne (HPLC) w zakresie ubytków stabilizatorów. Po przyspieszonym starzeniu zawartość modyfikatorów i stabilizatorów uległa obniżeniu w stosunku do prochów wyjściowych. Starzenie w podwyższonej temperaturze nie wpłynęło na zmianę geometrii prochów starzonych w stosunku do prochów wyjściowych. Dla większości badanych prochów, przyspieszone starzenie spowodowało nieznaczne podwyższenie kaloryczności względem prochów wyjściowych. Uzyskano porównywalne wartości gęstości helowej dla prochów przed i po starzeniu, wszystkie mieściły się w granicach błędu. Przyspieszone starzenie nie wpłynęło znacząco na zmiany żywości dynamicznej pomiędzy prochami starzonymi i wyjściowymi. A zatem, badane NC prochy modyfikowane nie powinny zmienić na tyle swoich właściwości w trakcie 10 lat przechowywania w temperaturze 25 °C, aby stać się niestabilne, tj. niebezpieczne podczas przechowywania i/lub aby nie spełnić wymogów balistycznych.
12
Content available remote Simultaneous determination of multiple components in Fuke Yangrong pill by HPLC
EN
Fuke Yangrong pill, a traditional Chinese patent medicine, with the functions of nourishing qi and blood, soothing liver and relieving depression, regulating menstruation and removing blood stasis, is composed of 16 Chinese medicinal herbs. For quality control purpose, an HPLC method was established for simultaneous quantification of paeoniflorin, hesperidin and ligustilide in Fuke Yangrong pill. With acetonitrile-0.1% formic acid as mobile phase, gradient elution was carried out using Agilent ZORBAX Eclipse Plus C18 column (250 mm × 4.6 mm, 5.0 μm) at 1.0 mL min⁻¹. Detection wavelength was set at 230 nm for paeoniflorin, 280 nm for hesperidin and ligustilide. The temperature was 30 °C. There was a good linearity between the peak area and the concentration of each component to be measured within their linear range (r ≥ 0.9994). The average recoveries were between 98.6% and 102.6% with RSDs no more than 2.93%. This method was validated to be accurate and convenient, which is suitable for the quality control of Fuke Yangrong pill.
EN
Codonopsis Radix (CR) is recorded as the roots of Codonopsis pilosula, C. pilosula var. modesta and Codonopsis tangshen. It is difficult to evaluate the quality of CR because of the existence of many original plants. In this paper, a strategy integrating chromatographic analysis and chemometrics for the quality control of CR is proposed. Systematic analysis of the chemical composition of CR was achieved through high performance liquid chromatography (HPLC) fingerprinting. Based on the HPLC fingerprinting data, chemometrics, including unsupervised principal component analysis (PCA) and supervised orthogonal partial least squares-discrimination analysis (OPLS-DA), were applied to classify all CR samples. Components with variable importance in projection values higher than 1 in the OPLS-DA model were selected as potential chemical markers for distinguishing the origins of CR. Finally, an HPLC method was validated for determining the five characteristic ingredients in the CR samples. HPLC characteristic fingerprints showed 17 common peaks for C. pilosula, 13 for C. pilosula var. modesta, and 9 for C. tangshen, and all of them showed good similarity (>0.9). Additionally, there were 9 common peaks for all CR samples with relatively poor similarity, ranging from 0.607 to 0.970. PCA could differentiate CR from the three origins, except for a partial overlap between C. pilosula and C. pilosula var. Modesta, and the OPLS-DA model achieved excellent classification results. Eight components (peaks 12, 8, lobetyolin, 10, codonopsin І, syringin, 3, and 11) were selected as potential chemical markers. There was a large discrepancy in the contents of the five characteristic ingredients in all samples, with the relative standard deviation ranging from 36.0% (lobetyolin) to 85.9% (atractylenolide Ⅲ). The average contents of the five characteristic ingredients were similar between C. pilosula and C. pilosula var. modesta samples and notably higher than those of C. tangshen samples. Consequently, a rapid, precise, and feasible strategy was established for the discrimination and quality control of CR with different origins.
EN
In this study, we propose a simple, cost-effective, and sensitive high-performance liquid chromatography with both detection techniques such as diode-array detection and fluorescence detection (HPLC-DAD-FLD) for the determination of nesfatin-1 in fetal bovine serum samples. The limit of detection (LOD) and limit of quantification (LOQ) for nesfatin-1 were set at satisfactory values in the range 0.22–0.35 mg mL⁻¹ and in the range 0.67–1.05 mg mL⁻¹, respectively (at two different wavelengths (DAD) and at four different wavelengths (FLD)). Analyte concentrations were determined as the average value from fetal bovine serum matrix samples. The preliminary results show that the SPE procedure on Isolute Si-TsOH (SCX-3) could be used for further nesfatin-1 analyses in human serum samples. Both the SPE technique, chromatographic analysis with gradient elution mode and detection technique are fast and convenient.
EN
The analysis of phenolic acids (PAs) is of great importance, because they are frequently present in natural products and their derivatives, and these compounds also have multiple beneficial effects to human health. This work is focusing on the separation of seven PAs (caffeic acid, coumaric acid, gallic acid, ferulic acid, protocatechuic acid, sinapic acid, and syringic acid), in a reversed-phase liquid chromatographic (RP-HPLC) isocratic method using a hydrophilic deep eutectic solvent (DES) as a mobile phase additive. The analysis was carried out with a diode array detector. The used DES was composed by choline chloride and glycerol, and it was characterized by infrared spectroscopy. The combination of choline chloride:glycerol (1:4) added at 0.25% to mobile phase composed of 0.15% formic acid aqueous solution and methanol (80:20), showed the best separation for target analytes. The new proposed method was validated, and results indicated that the proposed method is linear, selective for almost all analytes, provided high sensitivity with limit of detection ranges from 0.009 to 0.023 mg mL⁻¹, and has satisfactory precision and accuracy, with values of relative standard deviation of 0.24-2.65% and recoveries of 97.97-109%, respectively. Additionally, this method was successfully applied to simultaneous determination of phenolic acids in three kinds of samples of powder to prepare lemon flavour drink enriched with black tea extract.
EN
There has been a lively interest on macrocyclic polyamine alkaloids due to their remarkable pharmacological activities such as anti-tumor, anti-inflammatory, anti-Alzheimer's disease and anti-parasitic. Tripterygium wilfordii is a widely used traditional Chinese medicine, which is abundant in alkaloids including macrocyclic polyamine alkaloids. However, there are rarely studies on macrocyclic spermidine alkaloids of T. wilfordii so far. In this article, we use three known macrocyclic spermidine alkaloids celafurine, celabenzine and celacinnine, and successfully develop a simple and sensitive HPLC method for simultaneous quantification of macrocyclic spermidine alkaloids in root, stem and leaf of T. wilfordii.
EN
Astaxanthin and canthaxanthin are carotenoids produced mainly by algae, fungi and bacteria. These dyes give the characteristic pink-orange color to salmon, shrimp and flamingo feathers. In the case of farm animals, astaxanthin and canthaxanthin are added to the feed, and their amount is strictly established and should not exceed certain limits. The article presents a method of determination of astaxanthin and canthaxanthin by HPLC method. This analysis determines whether these dyes are detected in the product and what their content are. This makes it possible to assess compliance with the limits and often also to determine the origin of the product.
PL
Astaksantyna i kantaksantyna to karotenoidy wytwarzane głównie przez algi, grzyby i bakterie. Barwniki te nadają charakterystyczny różowo-pomarańczowy kolor piórom łososi, krewetek i flamingów. W przypadku zwierząt gospodarskich astaksantyna i kantaksantyna są dodawane do paszy, a ich ilość jest ściśle określona i nie powinna przekraczać określonych limitów. W artykule przedstawiono metodę oznaczania astaksantyny i kantaksantyny metodą HPLC. Ta analiza określa, czy barwniki te są wykrywane w produkcie i jaka jest ich zawartość. Pozwala to ocenić przestrzeganie limitów, a często także określić pochodzenie produktu.
EN
Polymeric building materials and equipment for indoor use in spaces intended for people may, in an essential way, contribute to the deterioration of wholesome quality of life. Phthalates, present in many products, constitute an omnipresent group of compounds used widely as plasticisers. The research results show that these substances may negatively impact human health, and thus European Union has implemented several regulatory measures restricting their use. Manufacturers and suppliers must comply with these regulations. As a result, it is necessary to investigate and determine the contents of phthalates in these materials. This paper presents the analytic profile of the method of marking phthalates extracted from polyvinyl chloride using HPLC chromatography with UV-VIS detection and selected results obtained in examinations of materials used in interior design. The results of described examinations of phthalates content indicate that not all materials recommended by manufacturers may be used indoors in spaces intended for people. The method was verified for its suitability for routine analyses of materials made of PVC and submitted for attestation. The elaborated method can be used to determine the banned phthalates’ presence in PVC. The method allows for detecting these phthalates at the level required by the REACH regulation, and its validation parameters are highly satisfactory considering a very complex matrix.
PL
Przedstawiono zastosowania materiałów mezoporowatych jako adsorbentów w procesie zatężania analitu metodą ekstrakcji w układzie ciecz-ciało stałe. Najczęściej stosowanymi adsorbentami są mezoporowate krzemionki oraz węgle. Modyfikacja powierzchni adsorbentów może przyczynić się do zwiększenia ich selektywności wobec adsorbowanych substancji. Metoda ekstrakcji w układzie ciecz-ciało stałe jest najczęściej stosowana podczas oznaczania substancji metodami chromatograficznymi (HPLC, UPLC, GC).
EN
A review, with 29 refs., of historical and new methods of obtaining mesoporous materials, including their properties and applications. The use of these materials in the detn. of trace amts. of an analyte was discussed. Particular attention was paid to the types and methods of preparing the porous phase for anal. purposes, its properties and the method of sepn. from the analyte (molecular imprinting, magnetic nanoparticles).
PL
W artykule przedstawione zostały zagadnienia związane z opracowaniem metodyki chromatograficznego oznaczania wielopierścieniowych węglowodorów aromatycznych w próbkach gleb. Do tego celu stosowano chromatograf cieczowy serii Vanquish Core firmy Thermo Scientific wyposażony w detektor fluorescencyjny (FLD) i detektor UV-ViS. W ramach prowadzonych badań określono optymalne parametry pracy chromatografu, takie jak: objętość próbki, rodzaj eluentów, szybkość przepływu eluentów, gradient eluentów w trakcie analizy chromatograficznej i czas analizy, oraz dobrano kolumnę chromatograficzną umożliwiającą selektywny rozdział analitów. Następnie wykonano kalibrację układu chromatograficznego i walidację metody analitycznej oznaczania WWA, stosując roztwory kalibracyjne opracowane na podstawie roztworu wzorcowego PAH-Mix nr ref. 722393 firmy Macherey-Nagel. Walidacja metody analitycznej obejmowała wyznaczenie liniowości, odchylenia standardowego, względnego odchylenia standardowego, granicy wykrywalności (LOD) i granicy oznaczalności (LOQ) badanych WWA. Chromatograficzna metoda identyfikacji WWA w próbkach gleb wymaga przeprowadzenia analitów z matrycy stałej do matrycy ciekłej (etap izolacji), oczyszczenia próbki z substancji przeszkadzających oraz zagęszczenia ekstraktu (etap wzbogacania). W celu opracowania metody oznaczania WWA w próbkach gleb sprawdzono 3 metody przygotowania próbek do analizy chromatograficznej HPLC: metodę A (metoda QuEChERS), metodę B (ekstrakcja rozpuszczalnikiem w aparacie Soxhleta) i metodę C (ekstrakcja rozpuszczalnikiem wspomagana wytrząsaniem). Otrzymane ekstrakty były następnie oczyszczane na wybranym materiale sorpcyjnym: MgSO4 i PSA (metoda A), CN/SiOH (metoda B) i Al2O3 (metoda C). Do przetestowania wybranych metod przygotowania próbek gleby do analizy chromatograficznej HPLC wykorzystano glebę wzorcową PAHs by HPLC40g (SQC017-40G) firmy Sigma Aldrich, o znanych stężeniach analitów. Oczyszczone ekstrakty poddano analizie chromatograficznej HPLC, obejmującej identyfikację oraz ilościowe oznaczenie poszczególnych WWA, oraz obliczono stopnie odzysku analitów. Na podstawie analiz chromatograficznych i stopni odzysku wytypowano optymalną metodykę przygotowania próbek gleb do analizy chromatograficznej pod kątem oznaczania wielopierścieniowych węglowodorów aromatycznych. Opracowaną metodykę oznaczania WWA w próbkach gleb przetestowano na rzeczywistych próbkach gruntu pobranych z 2 otworów badawczych zlokalizowanych na terenie kopalni ropy naftowej usytuowanej w południowo-wschodniej Polsce.
EN
The article presents issues related to the development of a methodology for the chromatographic determination of polycyclic aromatic hydrocarbons in soil samples. For this purpose, a Vanquish Core series liquid chromatograph by Thermo Scientific equipped with a fluores­cence detector (FLD) und UV-ViS detector was used. As part of the research, the optimal parameters of the chromatograph work were determined, such as sample volume, type of eluents, eluent flow rate, eluent gradient during the chromatographic analysis and analysis time, and the chromatographic column was selected to enable selective separation of analytes. Then, the chromatographic system was calibrated and the analytical method for PAH determination was validated using calibration solutions prepared on the basis of the PAH-Mix standard solution ref. 722393 from Macherey-Nagel. The validation of the analytical method included the determination of results linearity, standard deviation and relative standard deviation, as well as limit of detection (LOD) and limit of quantification (LOQ) of the tested method. The chromatographic method of identifying PAHs in soil samples requires the transfer analytes from a solid matrix to a liquid matrix (isolation stage), removal of interfering substances from the sample and concentration of extracts (enrichment stage). Soil samples were tested with 3 methods of sample preparation for HPLC analysis: method A (QuEChERS method), method B (solvent extraction in a Soxhlet apparatus), method C (solvent extraction with shaking). The obtained extracts were then purified on the selected sorption material: MgSO4 and PSA (method A), CN/SiOH (method B) and Al2O3 (method C). Standard soil PAHs by HPLC40g (SQCo17-40g) from Sigma Aldrich with known analyte concentrations was used to test selected methods of preparing soil samples for HPLC chromatographic analysis. The purified extracts were subjected to HPLC chromatographic analysis including identification and quantification of individual PAHs, and the recovery rates of the analytes were calculated. On the basis of chromatographic analyzes and degrees of recovery, the most optimal methodology for preparing soil samples for chromatographic analysis for the determination of polycyclic aromatic hydrocarbons was selected. The developed methodology for determination of PAHs in soil samples was tested on real soil samples collected from 2 boreholes located in an oil mine site in south-eastern Poland.
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