Voltammetric determination of β-carotene in raw vegetables and berries in Triton X100 media

Electrochemical behavior of beta-carotene in polar organic media and solubilized systems has been investigated. beta-Carotene is irreversibly oxidized at 500 and 920 mV on glassy carbon electrode in 0.1 M LiClO4 ethanol containing 10% of CH2Cl2. Effect of surfactants (cationic, nonionic and anionic) on voltammetric characteristics of beta-carotene oxidation has been evaluated. High concentrations of surfactants facilitate the electrooxidation of beta-carotene independently of surfactant type. The increase of oxidation current by 7-11% has been obtained in the presence of nonionic surfactant. The best results have been observed in 10 mM Triton X100 media. The peak current showed a linear dependence with the beta-carotene concentration over the range 10-380 mu M. The calculated detection limit was 2.5 mu M and the quantification limit was 8.3 mu M. Liquid extraction of beta-carotene with dichloromethane from raw vegetables and berries has been developed. Quantitative determination of beta-carotene in real samples using cyclic voltammetry in Triton X100 media combined with preliminary extraction has been carried out. The results obtained are in good agreement with data of nutrient database for standard references. (C) 2012 Elsevier B.V. All rights reserved.