Abstract:
:In everyday life, a macroscopic valve is a device with a movable control element that regulates the flow of gases or liquids by blocking and opening passageways. Construction of such a device on the nanoscale level requires (i) suitably proportioned movable control elements, (ii) a method for operating them on demand, and (iii) appropriately sized passageways. These three conditions can be fulfilled by attaching organic, mechanically interlocked, linear motor molecules that can be operated under chemical, electrical, or optical stimuli to stable inorganic porous frameworks (i.e., by self-assembling organic machinery on top of an inorganic chassis). In this article, we demonstrate a reversibly operating nanovalve that can be turned on and off by redox chemistry. It traps and releases molecules from a maze of nanoscopic passageways in silica by controlling the operation of redox-activated bistable [2]rotaxane molecules tethered to the openings of nanopores leading out of a nanoscale reservoir.
journal_name
Proc Natl Acad Sci U S Aauthors
Nguyen TD,Tseng HR,Celestre PC,Flood AH,Liu Y,Stoddart JF,Zink JIdoi
10.1073/pnas.0504109102keywords:
subject
Has Abstractpub_date
2005-07-19 00:00:00pages
10029-34issue
29eissn
0027-8424issn
1091-6490pii
0504109102journal_volume
102pub_type
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