Systems and methods for achieving filtration are provided that utilize agglomerates or granules of nanoparticles. The agglomerates or granules of nanoparticles may be used as and/or incorporated into a HEPA filtration system to remove solid or liquid submicron-sized particles, e.g., MPPS, in an efficient and efficacious manner. The filtration systems and methods are provided that utilize agglomerates or granules in a size range of about 100-500 microns. The agglomerates or granules of nanoparticles exhibit a hierarchical fractal structure. In the case of agglomerates of nanoparticles, porosities of 0.9 or greater are generally employed, and for granules of nanoparticles, porosities that are smaller than 0.9 may be employed. Filter media formed from the agglomerates or granules may be formed from materials such as carbon black and fumed silica, and may be employed in baffled or non-baffled filtration apparatus.