Platinum nanoparticles are usually in the form of a suspension or colloid of nanoparticles of platinum in a fluid, usually water. A colloid is technically defined as a stable dispersion of particles in a fluid medium (liquid or gas).
PN 0100 (OTTOKEMI) Platinum Nanopowder, APS 20-30 nm, 99.5% - used as catalysis, medicine, and the synthesis of novel materials with unique properties.