Abstract

The reaction between Fremy's salt and α-tocopherol (VE), ascorbic acid (VC) and its lipophilic derivatives ascorbyl-6-caprylate (VC-8), 6-laurate (VC-12) and 6-palmitate (VC-16) were studied by stopped-flow ESR spectroscopy in cetyl trimethylammonium bromide (CTAB) and sodium dodecyl sulfate (SDS) micelles, as a model reaction of these antioxidants with alkyl peroxy radicals in biological systems. The second order rate constants for the reaction of Fremy's salt with VE in CTAB and SDS micelles were found to be 7.9 × 10 3 and 2.2 M −1 s −1, respectively, with as high as a 3600-fold variation. Rate constants for VC, VC-8, VC-12 and VC-16 are 4.3, 35, 53 and 56 × 10 3 M −1 s −1 and 3.3, 2.7, 1.2 and 0.86 × 10 3 M −1 s −1 in CTAB and SDS micelles, respectively. The results demonstrate remarkable effects of the charge type of the micelles and the side-chain of the antioxidants on the antioxidation reactivity in the micelles. It reveals that the inter-micellar diffusion may be the rate-limiting step for antioxidation carried out in micelles.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.