A method is disclosed of assembling building blocks into supraparticles. The method includes applying a first solvent on a template of patterned recessed regions to wet surfaces of the recessed regions; applying a second solvent on the template of patterned recessed regions, the building blocks suspended in the second solvent; wherein the first solvent and the second solvent are partially miscible, resulting in negligible interfacial surface tension between the first and second solvents; and wherein droplets of the second solvent diffuse droplets of the first solvent in the recessed regions, thereby assembling the building blocks into the supraparticles in the recessed regions.