The particle drifting effect: A combined function of drug and colloidal properties

Nanosized drug particles and colloids enhance drug permeability and bioavailability through the particle drifting effect, but outcomes vary by drug, colloid, and formulation. This study used biphasic diffusion experiments and mass transport analyses to evaluate how factors like size, number, and type influence this effect.

Results showed that particle drifting is a sequential process of dissolution or dissociation in the diffusional boundary layer, followed by free drug absorption. The rate-limiting step varies by condition, while bile micelle dissociation and bile salt absorption further enhance drug uptake. These findings highlight the dynamic nature of the effect and support better formulation strategies for improved bioavailability.