A prolific chemist and inventor, Joe DeSimone wondered whether the manufacturing techniques that have given us cheap and ubiquitous electronics might have a use in medicine. The answer is yes. DeSimone has invented a roll-to-roll method for customized manufacturing of micro- and nanoparticles for pharmaceutical use. DeSimone’s lab has used the method, called PRINT (for Particle Replication in Non-wetting Templates), to create experimental particles including “Trojan horse” nanoparticles that can accumulate in tumors before releasing drugs, and polymer cells that mimic the size, shape and elasticity of red blood cells. A seasonal flu vaccine is the first PRINT-made product to enter clinical trials.