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Influence of sample preparation methods on the quantitation of selected tropane alkaloids from herb of Datura innoxia mill. by HPTLC

Oniszczuk A., Waksmundzka-Hajnos M., Gadzikowska M., Podgórski R., Oniszczuk T.

Acta Chromatographica

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2013

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Vol. 25, no. 3

545--554

EN

The aim of our paper was the examination of various procedures of extraction and purification methods on the yield of atropine and scopolamine in Datura innoxia extracts determined by high-performance thin-layer chromatography (HPTLC). In our experiments, the following extraction methods were used: percolation, ultrasound-assisted extraction (USAE) at various temperatures, and microwave-assisted extraction (MASE). The highest extraction yields of atropine and scopolamine were obtained by ultrasound-assisted extraction method and aqueous acetic acid or aqueous tartaric acid used as extractants. Crude extracts of D. innoxia herb were purified by use of various methods: solid-phase extraction-strong cation exchanger (SPE-SCX), SPE-C18, and liquid-liquid extraction (LLE). The best results of purification with satisfactory %RSD values were obtained by liquid-liquid extraction by use of dichloromethane from aqueous crude alkaloid extract alkalized to pH 12. HPTLC was performed on pre-coated plates Kieselgel 60 F254 in horizontal DS chambers by use of mobile phase: methanol-acetone-aqueous ammonia (5:4.5:0.5). The alkaloids’ content was determined in extracts by use of calibration curve method for atropine and scopolamine. Calibration curves were linear in range of 3.0–30 μg for scopolamine (R = 0.9980) and 2.6–26 μg for atropine (R = 0.9923). Limits of detection (LOD) and limits of quantification (LOQ) were 1.12 μg and 3.42 μg per spot for scopolamine and 0.89 μg and 2.82 μg per spot for atropine.

2

Effect of the vapour phase on the TLC separation of tropane alkaloids

Gadzikowska M., Jóźwiak G. W., Waksmundzka-Hajnos M.

Acta Chromatographica

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2010

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Vol. 22, no. 4

515--525

EN

The effect of conditioning the silica layer by mobile phase vapour or ammonia vapour on the retention of alkaloids eluted with non-aqueous mobile phases was examined. The effect of vapour phase composition on system efficiency, peak symmetry, and separation selectivity were also investigated. The most effective and selective systems were used for separation of the alkaloid fraction of Datura innoxia.

3

Chemometric characterization of the RF values of alkaloids for thin layer chromatographic systems of the type polar adsorbent -- multicomponent eluent

Waksmundzka-Hajnos M., Gadzikowska M.

Chemia Analityczna

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2001

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Vol. 46, No. 6

839-848

EN

Chemometric characteristic of several alkaloids of various groups was performed by the relationships of their retention coefficients Re against mpdifier concentration in eluent. Retention of alkaloids was investigated on silica layers using nonaqueous eluents containing different amounts of methanol in dichloromethane or using aqueous eluents (in pseudo-reversed phases) using methanol or acetonitrile as modifiers and 2% of glacial acetic acid. For poorly separated compounds in such systems alumina or magnesium silicate (Florisil) and dichloromethane — methanol mixtures as eluents were used. Selectivity of separation was analyzed by correlation diagramsRM Al vs RMSi and RM (Florisil for data obtained in nonaqueous systems. Presented results as RF vs C % plots or RM(12) diagrams permit to choose selective systems for the separation of particular groups of substances and enable identification and chemometric characterization of investigated alkaloids.

PL

Charakterystyka chemometryczna wielu alkaloidów z różnych grup była przeprowadzona poprzez zależności ich współczynników retencji RF od stężenia modyfikatora w eluencie. Badano retencje, alkaloidów na cienkich warstwach żelu krzemionkowego stosując eluenty niewodne zawierające różne ilości metanolu w dichlorometanie lub przy użyciu eluentów wodnych (układy pseudoodwrócone) przy użyciu metanolu lub acetonitrylu jako modyfikatorów z dodatkiem 2% lodowatego kwasu octowego. Dla słabo rozdzielonych związków w powyższych układach zastosowano układy z tlenkiem glinu lub krzemianem magnezu (Florisil) i mieszaniny dichlorometanu z metanolem jako eluenty. Selektywność rozdzielenia była analizowana grupowo poprzez diagramy korelacyjne RM1 vs RMSI oraz RM si vs RM(Florisil) dla danych uzyskanych w układach bezwodnych. Przedstawione wyniki jako krzywe zależności Rf vs C% lub diagramy korelacyjne RM1 vs RM12 dają możliwość znalezienia selektywnego układu dla rozdziału poszczególnych grup substancji i umożliwiają identyfikacje, i chemometryczną charakterystykę badanych alkaloidów.

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Commentary on the chromatographic retention of Chelidonium alkaloids

Gadzikowska M., Grynkiewicz G.

Acta Chromatographica

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2001

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No. 11

62-74

EN

Because basic isolates of Chelidonium majus L. constitute a valuable source of compounds with considerable medicinal potential, their chroma-tographic separation is a matter of continuous interest. Thus far, there has been no attempt to correlate the structural and retention properties of this biogenetically related but structurally diverse group of alkaloids. Taking as an example three representative sub-sets: chelidonine-type, protopine-type, and quaternary bases (berberine and benzo[c]phenanthridine-type) and analyzing their chromatographic behavior, we have concluded that polarity and lipophilicity descriptors derived from commonly used structural formulas are not sufficient for rationalization of their retention behavior. In particular, we draw attention to the exceptionally high polarity of protopine, which cannot be justified in terms of its polycyclic tertiary base structure bearing aminoketone functions in a medium size alicyclic ring, and would more appropriately be represented by a canonical formula indicative of the strong transannular interaction between the tertiary amine lone electron pair and the carbonyl carbon atom. As a consequence, the chromatographic mobility of protopine-type alkaloids might be categorized as that of quaternary rather than tertiary bases.

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Quantitative determination of chelidonine in Cynarein tablets by HPLC

Zagrodzka J., Gadzikowska M., Gołkiewicz W., Cieplucha G., Grynkiewicz G.

Acta Chromatographica

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2000

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No. 10

122-131

EN

A variety of HPLC conditions have been studied in the development of a method for selective and accurate determination of chelidonine hydrochloride in tablets of the complex herbal drug CynareinŽ. The result is a simple method based on extraction of chelidonine from tablet material then isocratic reversed-phase chromatography with UV detection. It has been found that chelidonine peak symmetry and tailing, and hence the accuracy of quantification, are highly dependent on the quality of the RP18 stationary phase.