Relationships between Interfacial Water, Ion Specificity and the Structures of Association Colloids and Antioxidant Distributions in Macroemulsions

Rutgers University New Brunswick, New Brunswick NJ

Investigators

Abstract

With this renewal award, the Organic and Macromolecular Chemistry Program continues its support of the work of Professor Laurence S. Romsted of the Department of Chemistry at Rutgers University in New Brunswick, NJ. The research will extend the PI's investigations in association colloid chemistry. There are two parts to this project. In the first part, Professor Romsted will investigate a of variety of association colloid structures which are are formed from the spontaneous aggregation of ionic surfactants. Using a chemical trapping technique, developed in the PI's laboratory, specific head group, counter ion, and hydration interactions that determine the structures and properties of these colloids will be investigated. The chemical trapping method will provide unique information concerning the chemical and physical properties of these species and will increase understanding of the balance of forces controlling their formation. In the second part of this proposal, the partition constants of antioxidants between the oil/interfacial and water/interfacial regions of oil/water/nonionic surfactant based emulsions will be determined. This will be accomplished by electrochemical monitoring of the reaction of an antioxidant with an arenediazonium ion along with UV spectroscopic measurements of the distribution of the antioxidant between the oil and water phases in the absence of surfactant. The experiments will systematically identify the relationships between antioxidant distributions and antioxidant structure, oil polarity, pH, and surfactant structure and charge. These latter experiments will identify factors affecting antioxidant distribution in emulsions and allow evaluations of antioxidant efficiency in emulsified foods. The research program will provide advanced training for undergraduate, graduate, and postdoctoral fellows, and will include extensive international collaborations. The experiments are expected to provide important conceptual basis for soft materials technologies especially in the areas of nutrition and health.