Adsorption Dynamics of Native and Alkylated Derivatives of Bovine Serum Albumin at Air–Water Interfaces

Adsorption Dynamics of α-Lactalbumin and β-Lactoglobulin at Air–Water Interfaces

“…According to Feijter and Benjamins (25), remains very low until a sufficient surface concentration has been reached because of the nonlinear nature of the surface equation of state. Experimental observation of such an induction period for bovine serum albumin (15) has been shown to be due to the fact that is insignificant whenever ⌫ is below a certain critical ⌫ crit because of the nonlinear nature of the adsorption isotherm. Wei et al (26) measured the kinetics of surface tension for five model proteins and found that the rate at which the surface tension decreases was correlated with the conformational stability of the proteins.…”

“…A 50 l aliquot of protein solution of 0.0247 wt% concentration was dripped from the top of a glass rod (5 mm diameter, 5 cm height) positioned above the air-water interface so that the solution spread uniformly on the top of the interface (14,15). It has been shown by Cho et al (19) that the loss of protein due to desorption from the air-water interface is negligible.…”

“…The work that needs to be done by an adsorbing protein molecule in order to clear an area A r at the air-water interface is given by s ϭ A r , [15] where is the surface pressure and A r is the area at the air-water interface that is cleared. The expressions for A s and A r for an ellipsoidal protein molecule in terms of its dimensions and the depth of penetration can be found elsewhere (38).…”

“…A computer-controlled Langmuir minitrough (KSV, Finland) with a Wilhelmy plate was employed for adsorption dynamics and spreading experiments as described elsewhere (14,15). ␤-Lactoglobulin and ␣-lactalbumin were radiolabeled with 14 C as described below in order to enable direct measurement of adsorbed protein concentration at the air-water interface.…”

Expulsion of bovine serum albumin from the air/water interface by a sparingly soluble lecithin lipid

“…At a physiological pH of 7.2, BSA has a net charge of −17 [27]. The dynamic adsorption and surface tension of the BSA have been studied [11,[29][30][31][32][33]. It was found that BSA absorbs fast to the interface at small times (1 s), and then it takes much longer times (1000-3000 s) to reach steady state or to fully "equilibrate," if reversible equilibrium could be defined at all, since adsorption may be nearly irreversible and surface denaturation is possible [34].…”