Thermal oxidation of lipids in monolayers. I. The nature of binding on silica

The purpose of this study was to investigate whether the oxidation of lipids in the ordered state differs from that in the bulk phase. Simple model systems of lipids adsorbed on silica were used as a monolayer model system. This part of the study was designed to provide a better understanding of the nature of lipid adsorption on silica. Isotherms were determined for a number of substrates differing in chain length and functional groups. The number of molecules adsorbed per unit area of silica was found to decrease with increasing chain length. Binding was also dependent on the type of functional group present. For the same length, the amount adsorbed was in the following order: alcohol >acid> ester, whereas binding strength was as follows: acid >ester> alcohol.