In our previous studies, we have noticed that in many cases, the properties of nanoparticle formulation depend strongly on surrounding medium. The fact that nanoparticles are studied and used, in aqueous medium, binds these characteristics together shape affects size distribution and charge affects stability, which again affects size distribution. Because particles are in nanoscale, properties can significantly differ from bulk properties which make it crucial to study these every time when physico-chemical modifications to nanoparticles are made. Few of the most important properties are size distribution, shape, charge, composition, purity, stability, and surface area. On another point of view, these same properties are also affecting nanoparticles’ toxicity. In addition, nanoparticles’ drug loading capacity, colloidal stability, and interactions with loaded drugs are related to their physico-chemical properties and are important for a functional drug delivery device. Biodistribution of nanoparticles, their interactions with cell components, and protein corona formation are determined by their properties. Nanoparticles’ properties are in key role when new biomedical applications are considered. Our results suggest that the multiangle LS methods could be used for the size, stability, and structure characterization of mesoporous nanoparticles. In case of PSi nanoparticles, strong correlation between LS result and specific surface area was found. Regarding to silica nanoparticles, the overestimation was attributed to agglomeration by analyzing radius of gyration and hydrodynamic radius. Comparison of particle radius from TEM and DLS revealed significant overestimation of the DLS result. We studied the properties of these mesoporous nanoparticles with two different multiangle LS techniques, DLS and static light scattering (SLS), and compared the results to dry-state techniques, TEM, and nitrogen sorption. Two fundamentally different silicon-based nanoparticles were made: porous silicon (PSi) from crystalline silicon and silica nanoparticles (SN) through sol-gel process. We hypothesize that conventional light scattering (LS) methods can be used for a rigorous characterization of medium sensitive nanoparticles’ properties, like size, stability, and porosity. Widely used characterization methods, dynamic light scattering (DLS), and transmission electron microscope (TEM) have both their weaknesses. Functionality of these nanoparticles depends on their properties which are often changing as a function of particle size and surrounding medium. Silicon-based mesoporous nanoparticles have been extensively studied to meet the challenges in the drug delivery.

Dynamic light scattering nanoparticle