Permeability of water and polar solutes in lipid bilayers

Kinetics of Disproportionation of Air Bubbles beneath a Planar Air–Water Interface Stabilized by Food Proteins

“…[8] one also needs to ensure that ∂γ /∂t P 0 (∂r/∂t). When this is not the case, the equation describing the dynamics of the bubble may also involve second derivatives of r with respect to t. For systems considered in this paper, however, the approximation applies for all but the very last stages of the bubble lifetime, when shrinkage accelerates, which normally falls below the resolution of our microscope.…”

“…[7] was used throughout. Equation [8] also neglects any viscous or other bulk forces that the bubble might experience during its shrinkage. Although these forces are important in solid food media such as cheese and dough, they are considered not to be significant in the low viscosity liquid media used in the present experiments.…”

“…If the variation of surface tension with r and time can be suitably described, then this can be incorporated into Eq. [7] or [8], allowing a numerical solution to the problem. Indeed this was the approach adopted previously (12).…”

“…Low-molecular-weight surfactants are generally quite mobile within the interface and do not pack well enough together to present a continuous barrier to gas diffusion (8). An exception may be where the surfactant layer is able to crystallize into some sort of defect-free solid layer around the bubble, as has been suggested for some sucrose-based surfactants (9).…”

Small, Stable, and Monodispersed Bubbles Encapsulated with Biopolymers

“…[9] Adsorption of surfactants to the surface of bubbles leads to the reduction of interfacial tension s (Equation 1), however conventional low-molecular weight surfactants do not prevent bubble dissolution, since they do not form a robust surface layer on the bubble surface and they rapidly desorb from the gas-liquid interface. [10] Recently however, Stone and coworkers demonstrated that patches of sucrose stearate can suppress bubble dissolution, due to surfactant crystallization on the bubble surface. [11] Alternatively, bubbles can be stabilized with lipids or biopolymers such as proteins or polysaccharides.…”