title: Flow injection chemiluminescence determination of the total phenolics levels in plant-derived beverages using soluble manganese(IV).
abstract: This study established a flow injection (FI) methodology for the determination of the total phenolic content in plant-derived beverages based on soluble manganese(IV) chemiluminescence (CL) detection. It was found that mixing polyphenols with acidic soluble manganese(IV) in the presence of formaldehyde evoked chemiluminescence. Based on this finding, a new FI-CL method was developed for the estimation of the total content of phenolic compounds (expressed as milligrams of gallic acid equivalent per litre of drink) in a variety of wine, tea and fruit juice samples. The proposed method is sensitive with a detection limit of 0.02 ng mL(-1) (gallic acid), offers a wide linear dynamic range (0.5-400 ng mL(-1)) and high sample throughput (247 samples h(-1)). The relative standard deviation for 15 measurements was 3.8% for 2 ng mL(-1) and 0.45% for 10 ng mL(-1) of gallic acid. Analysis of 36 different samples showed that the results obtained by the proposed FI-CL method correlate highly with those obtained by spectrophotometric methods commonly used for the evaluation of the total phenolic/antioxidant level. However, the FI-CL method was found to be far simpler, more rapid and selective, with almost no interference from non-phenolic components of the samples examined.
authors.affiliation: Institute of Chemistry, University of Białystok, ul. Hurtowa 1, 15-399 Białystok, Poland. nedyta@uwb.edu.pl
authors.forename: Edyta
authors.initials: E
authors.lastname: Nalewajko-Sieliwoniuk
authors.forename: Iwona
authors.initials: I
authors.lastname: Tarasewicz
authors.forename: Anatol
authors.initials: A
authors.lastname: Kojło
mesh_terms: D001628:Beverages / Q000032:analysis*; D005419:Flavonoids / Q000032:analysis* / Q000737:chemistry; D017022:Flow Injection Analysis / Q000379:methods*; D005557:Formaldehyde / Q000737:chemistry; D005707:Gallic Acid / Q000032:analysis / Q000737:chemistry; D008163:Luminescent Measurements / Q000379:methods*; D008345:Manganese / Q000737:chemistry*; D010636:Phenols / Q000032:analysis* / Q000737:chemistry; D059808:Polyphenols; D013662:Tea / Q000737:chemistry; D014920:Wine / Q000032:analysis
chemical_list: D005419:Flavonoids; D010636:Phenols; D059808:Polyphenols; D013662:Tea; D005557:Formaldehyde; D008345:Manganese; D005707:Gallic Acid