Future database search functionality will feature refinement factoring by keyword, size {type, value, unit, aggregation/agglomeration}, surface area {type, value, unit}, shape, composition {material type, molecular identity, crystallinity type, surface coverage level percentage, shell continuity type}, purity {value, units}, surface charge {type, value, unit}, solubility {type}, and biologic interaction selection: 

https://www.nanomaterialregistry.org/