With this in mind, the question arises as to what factors determine the efficiency of encapsulation. From a structural point of view, these are particle size and size distribution, which can be easily determined by dynamic light scattering (DLS). Particle size is of particular importance because it directly affects the amount of drug loaded into the core structure of the particles, as well as many other parameters, including drug release profile, targeting ability, cellular uptake potential, biological distribution efficiency, and tissue distribution .