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1

Photocatalysis combined with chromatographic methods as a new promising tool in drug metabolism studies – a review

Gawlik M., Skibiński R., Trawiński J., Komsta Ł.

Acta Chromatographica

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2018

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Vol. 30, no. 1

1--8

EN

The number of new drugs launched to the market is constantly increasing; however, the metabolism of many of them is still not fully established. The knowledge of drug metabolism pathways is crucial for the efficacy and safety of therapies and, in classical approach, requires the use of animals as well as human volunteers, but this kind of research is expensive and time-consuming. Therefore, nowadays, more and more biological and chemical in vitro methods are developed for the drug metabolism study. This review is focused on the photocatalytic degradation of chemicals and the application of this process in chromatographic methods of drug metabolism research. A theoretical background of photocatalysis and all its applications in a drug metabolism study were reviewed, and other in vitro methods that are actually used were summarized and discussed. Other analytical methods used in this area were also discussed and compared.

2

Comparison of ESI and APCI sources in Q-TOF mass spectrometer in photodegradation study of selected psychotropic drugs

Trawiński J., Skibiński R., Komsta Ł.

Acta Chromatographica

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2017

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Vol. 29, no. 2

161--172

EN

Ultra high-performance liquid chromatography (UHPLC) coupled with high-resolution quadrupole time-of-flight (Q-TOF) mass spectrometry was used for the preliminary photodegradation study of nine new generation psychotropic drugs. Based on the above method, two ionization sample modes — electrospray and atmospheric pressure chemical ionization were used for the registration of photodegradation profiles of the selected drugs. Multivariate chemometric analysis showed that electrospray ionization (ESI) method is more specific than atmospheric pressure chemical ionization (APCI) in high-resolution mass spectrometry (HR-MS) analysis of the analyzed psychotropic drugs. It was noticed that, with the use of ESI method, more potential photodegradation products can be identified and lower limits of its detection can be obtained.

3

Salting-out chromatography : a practical review

Komsta Ł., Skibiński R., Bojarczuk A, Radoń M.

Acta Chromatographica

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2011

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Vol. 23, no. 2

191--203

EN

This review focuses on the salting-out effect and its use in chromatographic analysis, mainly thin-layer chromatography. First, a theoretical background is given, focusing on the general salting-out theory and a comparison with chaotropic salt addition, practised recently in reversed-phase chromatography. All the salting-out chromatographic applications in literature (from the 1960s to the present moment) are then reviewed.

4

Multi-way analysis of retention of model compounds in thin-layer chromatography

Komsta Ł., Skibiński R., Gumieniczek A., Wojnar A.

Acta Chromatographica

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2010

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Vol. 22, no. 1

27--36

EN

The thin-layer chromatographic (TLC) retention of 35 model compounds has been investigated with ten screening mobile phases on six normal-phase and seven reversed-phase adsorbents. The retention factors formed two cubes with dimensions 35 × 10 × 6 and 35 × 10 × 7, respectively, which enabled three-way analysis by PARAFAC. A one-component PARAFAC model was optimum in both cases and two-component models performed worse. The one-component model explained 78.8% of the variance in normal-phase chromatography and 94.2% of the variance in reversed-phase chromatography. These results showed that the major variability of the retention factor ( R F ) can be modelled as the product of three factors related to the substance itself, the mobile phase, and the adsorbent. R F modelling was substantially better than using k or R M (rate mobility) values.

5

Reversed-phase TLC study of the lipophilicity of some 3-hydroxy-1,2-benzisoxazoles substituted in the benzene ring

Sławik T., Skibiński R., Paw B., Działo G

Acta Chromatographica

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2009

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Vol. 21, no. 2

251--258

EN

The relative lipophilicity, R M0 , and specific hydrophobic surface area of eleven 3-hydroxy-1,2-benzoisoxazoles substituted in the benzene ring (two isomeric fluoro, three isomeric chloro, three isomeric bromo and dibromo derivatives, and a nitro derivative) have been studied by reversed-phase thin layer chromatography (RP-TLC) on silica gel RP-C18 plates with methanol-water mixtures as mobile phases. Linear correlation between the volume fraction of methanol and R M values over a limited range was established with high correlation coefficients ( r > 0.99). Lipophilicity R M0 was compared with computed partition coefficients IAlogP, A logP s , clogP, milogP, logP KOWIN , and xlogP. The best correlation ( r > 0.9) was found between R M0 and logP KOWIN and xlogP values. Principal-components analysis (PCA) was also used to compare R M0 values with computed partition coefficients. The chromatographic behaviour of 3-hydroxy-1,2-benzisoxazoles was compared with that of their bioisosteric analogues 1,2-benzisot-iazolonoles. Experimental R M0 values for both groups of compounds were in accor-dance with the equation R M0 aR M0 +b(r> 0.9).

6

Comparative validation of densitometric and videodensitometric determination of lovastatin and simvastatin in pharmaceuticals

Komsta Ł., Skibiński R., Hopkała H., Winiarczyk-Serwacka M.

Chemia Analityczna

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2007

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Vol. 52, No. 5

771-779

EN

Densitometric and videodensitometric methods for determination of lovastatin and simva-statin in commercially available pharmaceutical have been described. Analysis was performed using HPTLC Si F254 plates and hexane-methylethylketone (55:45 v/v) mobile phase. Densitometric detection was performed at 230 nm, and videoscanning at 254 nm. Calibration plots were constructed in the range 4-16 &mi; g per spot for both drugs. Calibration data were subjected to statistical analysis using AIC criterion. Quadratic regression was finally chosen. Active substances were extracted from tablets with methanol. Densitometric method was much more precise than videodensitometric one. However, no significant differences in the accuracy between both procedures were observed. The proposed methods can be used in routine drug analysis due to their precision, accuracy, and relatively low consumption of materials and reagents.

PL

W pracy opisano densytometryczną i wideodcnsylometryczną metodę oznaczania lowasta-tyny i simwastatyny w dostępnych na rynku polskim preparatach farmaceutycznych. Analizę przeprowadzono na płytkach HPTLC pokrytych żelem krzemionkowym z użyciem fazy ruchomej o składzie heksan-metyletylketon (55:45 v/v). Detekcję densytometryczną przeprowadzono przy długości fali 230 nm, a wideoskanowanie przy 254 nm. Krzywe kalibracyjne skonstruowano w zakresie stężeń 4-16 &mi; g na plamkę. Dane kalibracyjne zostały poddane analizie statystycznej i na podstawie kryterium AIC wybrano regresję kwadratową. Ekstrakcję z tabletek przeprowadzono metanolem. Pomiędzy obiema metodami nie stwierdzono różnic w dokładności, natomiast densy tometria odznaczała się wyraźnie lepszą precyzją. Proponowana metoda jest dokładna i precyzyjna, może być użyta w rutynowej analizie produktów leczniczych.

7

Analysis of some non-selective calcium-channel blockers in normal- and reversed-phase high performance liquid chromatography

Skibiński R., Misztal G., Asarabowski K.

Chemia Analityczna

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2005

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Vol. 50, No. 3

561-573

EN

Chromatographic separation conditions for seven non-selective calcium-channel blockers were optimised. The separations were performed via normal- and reversed-phase high performance liquid chromatography using three different column packings: C18 , C8 and Si, and applying isocratic elution and spectrophotometric detection. The effect of the pH and the concentration of methanol, acetonitrile and propan-2-ol in the mobile phase on the retention and separation quality of the studied compounds were examined.

PL

W pracy zoptymalizowano warunki rozdziału siedmiu nieselektywnych blokerów kanałów wapniowych. Rozdział przeprowadzono za pomocą wysoko sprawnej chromatografii cieczowej w normalnym i odwróconym układzie faz. Zastosowano kolumny z trzema rodzajami wypełnień: C18, C8 i Si, elucję izokratycznąoraz detekcję spektofotometryczna. Zbadano wpływ pH oraz stężeń metanolu, acetonitrylu i propan-2-olu w fazie ruchomej na retencję i rozdział analizowanych związków.

8

NP- and RP-HPLC analysis of new generation antidepressant drugs

Skibiński R., Misztal G.

Chemia Analityczna

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2002

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Vol. 47, No. 4

531-538

EN

Two methods of separation of six new generation antidepressant drugs by high performance liquid chromatography in normal (NP-HPLC) and reversed phase (RP-HPLC) were developed. In both cases isocratic elution and spectrophotometric detection at 210 nm were used. The influence of pH changes and modificator concentration in mobile phase on the retention and separation of the analyzed substances was examined.

PL

Opracowano dwie metody rozdziału sześciu leków przeciwdepresyjnych nowej generacji za pomocą wysokosprawnej chromatografii cieczowej w normalnym (N P—HPLC) i odwróconym (RP-HPLC) układzie faz. W obu przypadkach zastosowano elucję izokratyczną oraz detekcję spektrofotometrycznąprzy długości fali 210 nm. Zbadano wpływ zmian pH oraz stężenia modyfikatora w fazie ruchomej na retencję i rozdział analizowanych substancji.

9

Application of HPLC for the determination of racemic fluoxetine and norfluoxetine in human plasma

Misztal G., Skibiński R., Olajossy M., Paw B., Przyborowski L., Hopkała H.

Chemia Analityczna

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2002

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Vol. 47, No. 2

229-240

EN

A selective, simple and accurate HPLC method for the determination of fluoxetine and nor-fluoxetine in blood plasma of patients is presented. The samples were chromatographed on a Nova-Pak Cs column after purification using a LiChrolut RP-I8 column. The mobile phase was methanol-acetonitrile-phosphate buffer of pH 2.65 (0.0657 mol L(-1)-triethyla-mine (10.9 + 32.7 + 56 + 0.4, v/v). Fluvoxamine was applied as an internal standard. The U V detection was carried out at 228 nm. The method was tested for linearity (over the range 20-600 ng mL'1) both for fluoxetine and norfluoxetine. The mean recoveries were 91.13% for fluoxetine and 95.69% for norfluoxetine. The described method has been successfully applied for the determination of these substances in plasma of patients, who received 20 mg fluoxetine daily.

PL

Przedstawiono selektywną, prostą i dokladnąmetodę HPLC oznaczania fluoksetyny i norfluo-ksetyny w osoczu krwi pacjentów. Próbki były oznaczane na kolumnie chromatograficznej Nova-Pak C8 po wyizolowaniu substancji do fazy stałej na kolumnach LiChrolut RP-18. Fazą ruchomą była mieszanina metanol-acetonitryl-bufbr fosforanowy o pH 2.65 (0.0657 mol L(-1)-trietyloamina(10.9 + 32.7 + 56 + 0.4, v/v). Jako standard wewnętrzny zastosowano fiuwoksaminę oraz detekcję w UV przy 228 nm. Liniowość opracowanej metody oceniono w granicach stężeń analizowanych substancj i od 20-600 ng mL(-1). Średni odzysk dla trzech różnych stężeń fluoksetyny w osoczu wynosi 91.13%, zaś dla norfluoksetyny 95.69%. Opracowana metoda może być zastosowana do oznaczenia tych substancj i u chorych, pobierających terapeutyczne dawki fluoksetyny 20 mg dziennie.

10

High performance liquid chromatographic determination of fluvoxamine and paroxetine i plasma

Skibiński R., Misztal G., Olajossy M.

Chemia Analityczna

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2000

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Vol. 45, No. 6

815-823

EN

A rapid, simple and accurate method for the determination of paroxetine and fluvo-xamine in human plasma is presented. Solid-phase extraction of these substances was carried out using a LiChrolut RP-18 column. A methanol-tetrahydrofuran-phosphate buffer at pH 2.65 (0.0657 mol 1-1) (53:5:42, v/v) was used as the mobile phase. Determination was performed using isocratic reversed-phase high-performance liquid chroma-tography (HPLC) with a Nova-Pak C]8 column and UV detection at 293 nm and 253 nm. The lower limit of quantitation for paroxetine and fluvoxamine was 10ngml-',when 1 ml plasma was extracted. Accuracies calculated at three concentrations in each of three separate runs were between 93.6 and 104.7% for paroxetine and 91.8 and 102.2% for fluvoxamine, and precision data were from 5.8 to 7.9 for paroxetine and from 2.2 to 8.8 for fluvoxamine.

PL

W pracy przedstawiono prostą, szybką i dokładną metodę HPLC do oznaczenia paro-ksetyny i fluwoksaminy w osoczu krwi. Do wyizolowania substancji z osocza zastosowano kolumienki LiChrolut RP-18. Jako fazę ruchomą stosowano mieszaninę: meta-nol-tetrahydrofuran-bufor fosforanowy o pH 2.65 (0.0657 mol1-1) (53+5+42, v/v). Proces chromatograficzny prowadzono w odwróconym układzie faz (kolumna Nova-Pak C]8) z zastosowaniem elucji izokratycznej i detekcji UV przy 253 nm dla fluwoksaminy i 293 nm dla paroksetyny. Limit detekcji dla obu substancji wynosi 10 ng ml 1-1 po ekstrakcji z osocza. Średni odzysk dla trzech różnych stężeń paroksetyny w osoczu wynosi od 93.6 do 104.7 % zaś dla fluwokaminy od 91.8 do 102.2%. Precyzja metody wynosi od 5.8 do 7.9 dla paroksetyny i od 2.2 do 8.8 dla fluwoksaminy.