The design and synthesis of artificial molecular machines (AMMs) with machine-like behavior, as it expressed at the nanoscale level, through the use of mechanically interlocked molecules (MIMs) opens the gates to unprecedented opportunities in many fields of science and technology, including the release of cargoes (drugs) mechanisorbed on to flat two-dimensional surfaces and on to nanoparticles. Metal-organic frameworks (MOFs) are two- or three-dimensional extended structures that are robust and porous to accommodate AMMs. Liang is currently exploring the repeated behaviors of molecular pumps working away-from-equilibrium on surfaces, promising a bright future it holds for not only chemistry but also for the materials and medical sciences. He used redox and acid-base chemistry to load and unload precisely a set of cargoes between a solution phase and solid-state supports. In these studies, MOF nanosheets and nanoparticles function like extended platforms, in addition to acting as coordinative organizers for arrays of artificial molecular pumps constructed of half dumbbells which can be threaded using pumping cassettes by multiple rings, one ring at a time, and then all released at once on command. Now, in addition to physisorption and chemisorption, a new concept - namely mechanisorption - is about to enter the lexicon of chemistry.
















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