Adsorption of nanoparticles and nanoparticle aggregates on membrane under gravity

Particle adsorption on lipid membrane is critical to biomedical applications. Gravity effect on the process has long been ignored. A combination of the upright and inverted configuration measurements was developed to exhibit that gravity causes a particle adsorption disparity on membrane between the different heights of medium. The more homogeneous adsorption tendency of nanoparticle aggregate compared to nanoparticle under the same gravitational motive force is attributed to the larger hydrodynamic diameter induced lower concentration disparity.