R. Miller et al., RELAXATION BEHAVIOR OF HUMAN ALBUMIN ADSORBED AT THE SOLUTION AIR INTERFACE, Colloids and surfaces. A, Physicochemical and engineering aspects, 76, 1993, pp. 179-185
The adsorption kinetics of human albumin (HA) at the aqueous solution/
air interface and the surface relaxation behaviour of HA adsorption la
yers after transient area disturbances are studied using an axisymmetr
ic drop shape technique (ADSA). Transient relaxation measurements were
performed with the ADSA technique by changing the volume of the pende
nt drop by definite increments. In the concentration interval studied,
the relaxation behaviour of HA is not diffusion controlled. Relaxatio
n phenomena observed during the induction time show the presence of st
ructured adsorption layers. The relaxation behaviour of a quasi-equili
brium HA adsorption layer is independent of the HA concentration. The
calculated apparent diffusion coefficients represent the order of magn
itude of the rate constant of the real mechanism. A comparison of resu
lts calculated from adsorption kinetics and relaxation data shows good
agreement with an apparent diffusion coefficient in the order of 0.00
1 cm2 s-1.