RESUMO
Acridinium salts, due to their chemiluminogenic properties, have found several applications in biomedical analysis as labels and indicators, where the assessment of emission intensity is used for the end-point detection. This work presents the use of chemiluminescent indicators in the form of selected acridinium esters in order to determine the antioxidant properties of exemplary formulations, namely quercetin, vitamin C and the dietary supplement, Apiextract. The principle of measurements is based on a change in the kinetics of emission decay derived from the acridinium cations in alkaline solutions of hydrogen peroxide in the presence of an antioxidant (the analyte). The proposed system makes a beneficial alternative to related methods, which mostly rely on the assessment of emission efficiency and use the luminometric standard luminol - due to superior parameters of acridinium chemiluminescence, among others - high temporary emission efficiency. The features of the proposed method are manifested by a shorter time period of analysis and lower background signals associated with the environmental influences, as compared to typical approaches. The chromatographic (RP-HPLC) analyses of the substrates and products generated during chemiluminogenic oxidation of acridinium cations under assay conditions are also presented.
