Adsorptive behavior of a globular protein with a monoglyceride monolayer spread on the aqueous surface

The dynamics of surface pressure(π) and of surface concentration (Г) of a14C radiolabeled β-lactoglobulin, a globular protein, adsorbed onto a spread monolayer of 1-monopalmitoyl-rac glycerol (named commonly as a monoglyceride), at the air-water interface were measured. The adsorption of14C labeled β lactoglobulin was enhanced at short times when C-16 monoglyceride of 73.4 and 24.7 μg was spread on the aqueous surface. However, the amounts of protein adsorbed at the steady state (after 10 h) were lowered with the values being 0.8 and 1.2 mg/m2, respectively. Spreading of such amount of monoglyceride that forms a dense packed monolayer onto air-water interface led to complete displacement of the protein from the aqueous surface after 2.5 h, possibly because of the surface pressure and exclusion effects.