USDA Post Doc Position
Laurence S. Romsted
Department of Chemistry and Chemical Biology
Rutgers, The State University of New Jersey
Piscataway, New Jersey, 08854
romsted@rutchem.rutgers.edu
732-445-3639 (office)
Postdoctoral Position on fundamental surfactant chemistry in micelles, emulsions, and nano- and microemulsions. Larry Romsted is a member of the Department of Chemistry and Chemical Biology at Rutgers, the State University of New Jersey. The project is part of a recently funded three-year grant from the United States Department of Agriculture and is part of a collaborative project with colleagues in the Rutgers Food Science department. The anticipated start date of the postdoctoral position is January 1, 2010, although the exact start date is flexible because life's timing and US visa problems are legion. The salary is based on experience and the position is renewable based on research progress.
Aim of the Project, Background Information, References
USDA Project Summary and Project Narrative
The primary aim of the research is to develop useful models determining the distribution of components, as expressed by partition constants, between the oil and interfacial and aqueous and interfacial regions of emulsions, in general and for antioxidants or oil distributions in particular in emulsions. This is a completely new approach to determining component distributions in opaque emulsions. Electrochemical kinetic measurements of the observed rate constant for reaction of an antioxidant with a arenediazonium ion probe are combined with models for component distributions in micelles and microemulsions. This research is also crucial for laying a firm basis for comparing antioxidant efficiencies in a variety of food emulsions and in particular for understanding how polyphenols and other antioxidants affect the stability of citral in nano- and micro- emulsions. We also plan to use NMR self-diffusion measurements to determine the distributions of polyunsaturated oils between the oil region and interfacial region of emulsions. Combining these results could lead to a new way to compare antioxidant efficiencies.
Below are some references on the development of our methods for determining antioxidant distributions. This work is carried out in collaboration with colleagues and their students in Spain. The two attached pdf files contain the text of the Project Summary and the Project Narrative for the USDA grant. Those parts of the proposal not concerned with antioxidant and oil distribution will be carried out by colleagues at the Rutgers Food Science Department.
Relevant References (Links are to pdf files of the full papers)
1. Effects of Temperature and Emulsifier Concentration on a-Tocopherol Distribution in a Stirred, Fluid, Emulsion. Thermodynamics of a-Tocopherol transfer between the Oil and Interfacial Regions. María José Pastoriza-Gallego, Verónica Sánchez-Paz, Sonia Losada-Barreiro, Carlos Bravo-Díaz, K. Gunaseelan, and Laurence S. Romsted. Langmuir, 2009, 25, 2646-2653.
2. Quantitative Determination of a-Tocopherol Distribution in a Tributyrin/Brij 30/Water Model Food Emulsion. Verónica Sánchez-Paz, Maria José Pastoriza-Gallego, Sonia Losada-Barreiro, Carlos Bravo-Díaz, K. Gunaseelan, Laurence S. Romsted, Journal of Colloid and Interface Science, 2008, 320, 1-8.
3. Determining a-Tocopherol Distributions between the Oil, Water, and Interfacial Regions of Macroemulsions: Novel Applications of Electroanalytical Chemistry and a Pseudophase Kinetic Model Gunaseelan, K.; Romsted, L. S., Gallego, M-J. P., Elisa González-Romero, E., Bravo-Díaz, C. Advances in Colloid and Interface Science, 2006, 123-126, 303-311.
USDA Project Summary: (Link to the pdf file)
USDA Project Narrative: (Link to the pdf file)