Fluorescent Molecular Logic Gates Driven by Temperature and by Protons in Solution and on Solid

Temperature-driven fluorescent NOT logic is demonstrated by exploiting predissociation in a 1,3,5-trisubstituted Δ 2 -pyrazoline on its own and when grafted onto silica microparticles. Related Δ 2 -pyrazolines become proton-driven YES and NOT logic gates on the basis of fluorescent PET (photoinduced electron transfer) switches. Additional PASS 1 and YES + PASS 1 logic gates on silica are also demonstrated within the same family. Beside these small-molecule systems, a polymeric molecular thermometer based on a benzofurazan-derivatized N-isopropylacrylamide copolymer is attached to silica to produce temperature-driven fluorescent YES logic.