Spectrophotometric determination of various polyanions with polymeric film optodes using microtiter plate reader

Autor: Sibel Naç, Nazangül Ünal, Nedime Dürüst, Mark E. Meyerhoff
Rok vydání: 2011
Předmět:
Zdroj: Analytica Chimica Acta. 699:107-112
ISSN: 0003-2670
DOI: 10.1016/j.aca.2011.05.007
Popis: Polycation-sensitive membrane optodes based on the chromoionophore 2',7'-dichlorofluorescein octadecylester (DCFOE) have previously been developed and used for determination of heparin via a titri metric method. In this study, it is shown that some other important polyanions such as PPS (pentosan polysulfate), DNA, xanthan, Na-alginate, and carrageenan (food additive) can also be readily determined by using DCFOE-basecl microtiter plate-format optodes (MPOs) and polycationic titrants that bind these polyanionic species. The optical sensors are prepared with poly(vinyl chloride) (PVC), polyurethane (PU), bis(2-ethylhexyl)sebacate (DOS), and 2',7'-dichlorofluorescein octadecylester (DCFOE) and exhibit reproducible and sensitive absorbance changes in response to the varying polycationic titrant concentrations. Three different polycations; protamine, poly-L-lysine and poly-L-arginine, are employed as titrants. The method has a detection limit of 1 mu g mL(-1), and a dynamic range of 1-40 mu g mL(-1). After the quantitative determinations are successfully demonstrated in buffered solutions, similar titrations are also performed in real samples. The method is validated by recovery studies in these samples. The average polyanion recoveries were quantitative [99.7(+/- 1.3) % for pastry cream with vanillin (protamine titrant); 100.4 (+/- 3.3) % for pastry gel with strawberry(PLA titrant), and 102.9(+/- 2.0) % for pastry gel with strawberry (PLL titrant)]. (C) 2011 Elsevier B.V. All rights reserved.
Databáze: OpenAIRE
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