title: The reaction between ABTS radical cation and antioxidants and its use to evaluate the antioxidant status of serum samples.
abstract: The 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical cation can be generated by incubation of ABTS and 2,2'-azo-bis(2- amidinopropane) at 45 degrees C. The ABTS radical cation is stable for several minutes at room temperature and reacts quantitatively and instantaneously with several antioxidants, such as Trolox, ascorbic acid, uric acid, cysteine, glutathione and bilirubin. In contrast, the ABTS radical cation reacts slowly with albumin. When serum is added to a solution of the ABTS radical cation, the bleaching of the radical follows biphasic kinetics, with a fast decay followed by a slow decay that takes place within several minutes. The fast decay is primarily due to uric acid, while the slow decay is related to the protein content of the sample. We propose that this procedure can provide an independent and simultaneous evaluation of the low molecular weight and protein antioxidants present in biological samples such as serum.
authors.affiliation: Centro Nacional de Investigaciones Científicas, La Habana, Cuba.
authors.forename: C
authors.initials: C
authors.lastname: Romay
authors.forename: C
authors.initials: C
authors.lastname: Pascual
authors.forename: E A
authors.initials: EA
authors.lastname: Lissi
mesh_terms: D000975:Antioxidants / Q000494:pharmacology*; D001205:Ascorbic Acid / Q000097:blood; D052160:Benzothiazoles; D001663:Bilirubin / Q000097:blood; D002839:Chromans / Q000494:pharmacology; D003545:Cysteine / Q000097:blood; D005978:Glutathione / Q000097:blood; D007202:Indicators and Reagents / Q000378:metabolism*; D013451:Sulfonic Acids / Q000378:metabolism*; D013696:Temperature; D013997:Time Factors; D014527:Uric Acid / Q000097:blood
chemical_list: D000975:Antioxidants; D052160:Benzothiazoles; D002839:Chromans; D007202:Indicators and Reagents; D013451:Sulfonic Acids; D014527:Uric Acid; C002502:2,2'-azino-di-(3-ethylbenzothiazoline)-6-sulfonic acid; D005978:Glutathione; D003545:Cysteine; D001205:Ascorbic Acid; D001663:Bilirubin; C010643:6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid