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1

Determination of microelements in sprouts grown on metal-enriched solutions by ion chromatography

Blicharska E., Komsta Ł., Kocjan R., Gumieniczek A., Kloc A., Kaźmierczak J.

Acta Chromatographica

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2014

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Vol. 26, no. 4

739--747

EN

The paper discusses a possibility to grow seeds on solutions of microelements and application of sprouts enriched in such a way as an alternative to commercial dietary supplements. It contains a short review of the approaches reported till now and a systematic experimental study, carried on the most frequently used seeds (Lens culinaris, Helianthus annuus, Vigna radiata, Glycine max, and Lepidium sativum).Seven metals (Fe, Cu, Zn, Ni, Co, Cd, and Mn) were studied. Seeds were grown on cellulose in 20°C temperature using deionized water enriched with metals in concentrations: 100, 50, 25, 12.5, 6.25, and 3.125 mg/L in a period of 4 days. The reference samples were the seeds grown on pure deionized water. Sprouts were mineralized by microwave radiation, and the metal content was quantified by ion chromatography with on-line post-column derivatization and spectrophotometric detection.The conclusions can be treated as general recommendations, which seeds should be grown and what concentrations of metals in solutions should be applied to provide good enrichment and to avoid risk of microelement overdose.

2

Densitometry, video-scanning and capillary electrophoresis for determination of valsartan and amlodipine in a combined dosage form: A comparative study

Inglot T. W., Gumieniczek A., Komsta Ł., Związek R.

Acta Chromatographica

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2013

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Vol. 25, no. 1

47-58

EN

Comparison of classical densitometry, video-scanning, and capillary electrophoresis was performed for determination of angiotensin II receptor antagonist, valsartan, and calcium channels blocker, amlodipine, in a combined dosage form. Thin layer chromatography was performed on RP8F254 TLC plates with a mobile phase consisting of acetonitrile-phosphate buffer at pH 9.0 (5:5, v/v) and temperature 20 °C. Densitometry was done in the reflectance mode at 217 nm for valsartan and in the absorbance mode at 370 nm for amlodipine. Video-scanning was elaborated at 254 and 366 nm for valsartan and amlodipine, respectively. For chromatographic analysis, calibration plots were constructed in the range of 0.4–2.8 μg per spot for valsartan and 0.02–0.14 μg per spot for amlodipine. Capillary electrophoresis (CE) was performed using a 75 μm × 94 cm fused silica capillary (72 cm effective length), 0.01 mol L-1 borate buffer at pH 8.0, 20 kV voltage, 30 °C temperature, hydrodynamic injection (10 mbar, 6 s) and UV detection at 237 nm. Calibration plots were constructed in the range of 0.1–0.6 mg mL-1 for valsartan and 0.005–0.03 mg mL-1 for amlodipine. All methods were validated in respect to robustness, specificity, stability, linearity, precision, and accuracy. Generally, statistical comparison between the methods did not show significant differences so all procedures are suitable for pharmaceutical analysis.

3

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.

4

Ion-selective electrodes for the determination of chlorpyramine an antihistaminic drug

Hopkała H., Drozd J., Gumieniczek A.

Chemia Analityczna

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2002

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Vol. 47, No. 1

75-82

EN

The ion-selective poly(vinyl chloride) membrane electrodes sensitive for chlorpyramine are described. The preparation of electrodes is based on the formation of ion-pairs: chlorpy-ramine-tetrakis(4-chlorophenyl)borate and chlorpyramine-reineckate with following solvents: 2-nitrophenyl octyl ether, bis(2-ethylhexyl)sebacate, bis(2-ethylhexyl)phosphate, tris(2-ethylhexyl)phosphate and dibutylsebacate. The electrodes were found to respond to chlorpyramine with sub-Nernstian slopes depending on the nature of the solvent mediators and the counter ion. The electrode based on chlorpyramine-tetrakis(4-chloro-phenyl)borate and 2-nitrophenyl octyl ether as solvent mediator provides a rapid and sensitive method for chlorpyramine hydrochloride determination. The results were found to agree with the active substance content declared by the manufacturer and with spectrophotometric determination.

PL

Opracowano jonoselektywne elektrody czule na chlorpyraminę, w których matrycą był polichlorek winylu), a substancją elektroaktywną pary jonowe: chlorpyramina-tetrakis (4-chlorofenylo)boran lub chlorpyramina-reineckan z następującymi rozpuszczalnikami: eterem 2-nitrofenylooktylowym, 6/s(2-etyloheksylo)sebacynianem, 6Ť(2-etyloheksylo)-fosforanem, /ri.y(2-etyloheksylo)fbsfbranem i dibutylosebacynianem. Elektrody wykazywały nieco mniejsze od nernstowskiego nachylenie w zależności od użytego przeciwjonu jak i rozpuszczalnika. Elektroda zawierająca parę onową chlorpyramina-tetrakis (4-chlorofe-nylo)boran i 2-nitrofenylooktylowy eter jako rozpuszczalnik posłużyła do opracowania czułej metody oznaczania chlorowodorku chlorpyraminy. Stwierdzono dobrą zgodność wyników oznaczeń z zawartością substancji czynnej deklarowanej przez producenta oraz z oznaczeniami przeprowadzonymi metodą spektrofotometryczną.

5

Analytical investigations of angiotensin converting enzyme inhibitors

Gumieniczek A.

Chemia Analityczna

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2002

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Vol. 47, No. 1

1-20

EN

The angiotensin converting enzyme (ACE) inhibitors are widely used in therapy, so the specific and sensitive methods are needed for the quantitative determinations of these drugs in pharmaceutical dosage forms and in biological material. The paper presents a review of the methods elaborated for the determination of the oldest drug — captopril containing the thiol group and the methods elaborated for the discrimination of newer, non-sulfhydryl compounds. The first part of paper presents the methods applied for the analysis of pharmaceuticals. The second part is devoted to the methods elaborated for the assays in biological material (blood, plasma, urine). The sensitivity of these methods and the techniques for the isolation of analytes from the matrix are especially regarded.

PL

Szerokie zastosowanie w lecznictwie inhibitorów ACE stworzyło konieczność opracowania selektywnych i czułych metod ilościowego oznaczania tych leków w preparatach farmaceutycznych oraz materiale biologicznym. Praca stanowi przegląd metod stosowanych do oznaczania najstarszego leku z tej grupy — kaptoprylu, zawierającego w cząsteczce grupę tiolowąoraz metod opracowanych do oznaczania nowszych, niesulfhydrylowych pochodnych. Pierwsza część artykułu obejmuje przegląd metod stosowanych do oznaczania inhibitorów ACE w preparatach farmaceutycznych. Druga część artykułu obejmuje przegląd metod opracowanych do oznaczeń w materiale biologicznym (krew, osocze, mocz). Szczególną uwagę zwrócono na czułość omawianych procedur oraz sposoby izolacji oznaczanych związków z matrycy biologicznej.

6

High-performance liquid chromatographic assay for perindopril in tablets

Gumieniczek A., Hopkała H.

Chemia Analityczna

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1998

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Vol. 43, No. 6

951-954

EN

A new, simple and accurate high-performance liquid chromatography method is presented for measuring perindopril in tablets, using a reversed-phase technique, UV detection at 211nm and quinapril as an internal standard. Linear detection response was obtained for the concentrations range from 0.1 to 0.5 ug ml(-1). The limit of detection was 50 ug ml(-l). Perindopril was extracted from tablets with methanol. The percentage of recovery ranged from 95.0 to 102.75 %.

PL

Opracowano nową, prostą i dokładną metodę chromatografü cieczowej w odwróconym układzie faz do oznaczania peryndoprylu w tabletkach, stosując detekcję UV przy 211 nm oraz kwinapryl jako wzorzec wewnętrzny. Dla zakresu stężeń od 0.1 do 0.5 mg ml(-l) otrzymano liniową zależność sygnału detektora, a limit detekcji wynosił 50 ug mI(-l). Substancję czynną ekstrahowano z tabletek metanolem, uzyskując procentowe wartości odzysku od 95.0 do 102.75%.