Journal of Lipid Research | |
Kinetics of the processes of desorption from fatty acid monolayers | |
David G. Cornwell1  Richard H. Matthews1  Gajanan S. Patil1  | |
[1] Department of Physiological Chemistry, The Ohio State University, Columbus, Ohio 43210; | |
关键词: lauric acid; myristic acid; palmitic acid; palmitoleic acid; oleic acid; surface pressure; | |
DOI : | |
来源: DOAJ |
【 摘 要 】
The surface area, A, of contracting fatty acid monolayers was measured as a function of time, t, at constant surface pressure. In the initial temporal phase, ln A was linear with √t. In a subsequent steady-state phase, ln A was linear with t. The initial desorption coefficient for sodium palmitate, Ki, and the steady-state desorption coefficient, Ks, varied directly with surface pressure and subphase pH, and these desorption coefficients also varied with the composition of the subphase buffer. However, the Ks/Ki, ratio was independent of these variables. The diffusion coefficient, D25, for sodium palmitate calculated from desorption coefficient ratios was 4.8 ± 0.6 × 10–6 cm2/sec. This value was in reasonable agreement with D25 for sodium palmitate measured by time-lag diffusion, 3.7 ± 0.6 × 10–6 cm2/sec. D25 values obtained for a series of fatty acids suggested that higher members of the series diffused as small aggregates averaging two to four molecules in size. Kinetic and diffusion data both supported a model for the desorption process described by Ter Minassian-Saraga.
【 授权许可】
Unknown