Hexyl Glucoside and Hexyl Maltoside Inhibit Light-Induced Oxidation of Tryptophan

We investigated the photo-protective effect of sugar-based surfactants-hexyl glucoside and hexyl maltoside-against light-induced oxidation of a monoclonal antibody. Reactive oxygen species are generated in solutions in the presence of light; these reactive species readily oxidize amino acids such as tryptophan. Hexyl glucosides and hexyl maltosides scavenge these reactive species and protect tryptophan residues from light-induced oxidation in a concentration-dependent manner. As a result of the scavenging process, hydrogen peroxide is formed, especially at high (millimolar) concentrations of the alkyl glycoside surfactants. These results suggest that hexyl glucoside and hexyl maltoside have the potential to protect tryptophan residues against light-induced oxidation. © 2013 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 103:409-416, 2014