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Antioxidant phenolic compounds in Salvia officinalis L. and Salvia sclarea L.

Jasicka-Misiak I., Poliwoda A., Petecka M., Buslovych O., Shlyapnikov V. A., Wieczorek P. P.

Ecological Chemistry and Engineering. S

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2018

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Vol. 25, nr 1

133-142

EN

The differences in the chemical composition of the phenolic compounds of Salvia officinalis versus Salvia sclarea growing in different habitats, were studied. First, the optimal solvent - methanol - for ultrasonic extraction of phenolic compounds from these plants was chosen experimentally. Total phenolic content and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assays were determined spectrophotometrically. Total phenolic content was in the range of 63.9 to 134.4 mg GAE/g of plant depending on the studied species. The highest antiradical activity was displayed by the methanol fractions of S. sclarea varieties (83 and 67%). HPLC-DAD analysis of extracts was done in order to identify the presence of individual phenolic compounds. This was done by comparison of their retention times with those observed for 17 commercially available standard compounds. The results showed differences in the phenolics composition, with plants collected on Crimean peninsula accumulating more phenolic acids than Polish varieties. In turn, the Polish varieties of sage contain bigger amount of flavonoids in their tissues.

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Application of Molecular Imprinted Polymers for Selective Solid Phase Extraction of Bisphenol A

Poliwoda A., Mościpan M., Wieczorek P. P.

Ecological Chemistry and Engineering. S

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2016

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Vol. 23, nr 4

651--664

EN

Selective molecularly imprinted polymers (MIPs) with bisphenol A as template were synthesized using the non-covalent imprinting approach. MIPs were prepared using thermally initiated polymerization with 1,1’-azobis(cyclohexanecarbonitryle) (ACHN) as initiator and ethylene glycol dimethacrylate (EDMA) as a cross-linking agent. The tested functional monomers included methacrylic acid, acrylamide, and 4-vinylpyridine. The selectivity of the BPA-MIP for the solid phase extraction of bisphenol A was tested in samples containing other related alkylphenols. The polymers prepared in acetonitrile using methacrylic acid or acrylamide as monomer showed the highest selectivity towards target analyte (the selectivity ratio 8:1, respectively for MIP and NIP). The proposed procedure has been proven to be an effective for selective extraction of bisphenol A in aqueous samples (recoveries over 85%) enabling detection and quantification limits of 25 and 70 μg/dm3, respectively based on 10 cm3 of sample volume, with relative standard deviations (RSD) lower than 6%. The obtained molecularly imprinted material showed interesting properties for selective extraction and preconcentration of studied analyte from large volumes of aqueous samples without any problems of cartridge clogging.

3

Ekstrakcja membranowa oraz ekstrakcja do fazy stałej jako efektywne techniki wydzielania i zatężania związków organicznych z próbek o złożonym składzie matrycy

Poliwoda A., Chrzanowska A. M., Orłowska K., Wieczorek P. P.

Chemik

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2014

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Vol. 68, nr 4

312--320

PL

Niniejsza praca stanowi przegląd metod analitycznych opracowanych do wydzielania, zatężania i oznaczania związków organicznych wykazujących aktywność biologiczną, w tym przede wszystkim ksenobiotyków oraz substancji endokrynologicznie czynnych, w próbkach o złożonym składzie matrycy.

EN

This article is a review of analytical methods developed for extraction, concentration and determination of biologically active organic compounds, especially xenobiotics and endocrine disrupting compounds in samples with complex matrix composition.

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Extraction of peptides from body fluids using supported liquid membranes

Poliwoda A., Wieczorek P. P.

Biocybernetics and Biomedical Engineering

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2008

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Vol. 28, no. 2

49-57

EN

Sample pre-treatment is a very important step in many analytical procedures, especially when the analyte is presented in low concentration in complex sample matrices. In this paper, potential using of the supported liquid membrane (SLM) technique as a sample preparation step in order to isolate, pre-concentrate and separate small peptides and phosphono dipeptides from aqueous solutions and body fluids is discussed. An influence of various parameters including carrier type, donor and acceptor phase compositions, presence of salts and proteins in analysed samples on extraction efficiency and selectivity is presented. Additionally, comparison of SLM extraction efficiency from aqueous samples and body fluids is presented. Finally, a fully automated system consisted of SLM extraction coupled on-line with HPLC-UV for the analysis of selected peptides from blood plasma is shown.