Yunyan Qiu and Liang Feng describe the mechanism and possible uses of nanoscale molecular pumps. These pumps are constructed to attract and concentrate rotaxanes. Reduction and oxidation (redox) reactions drive the pumps, changing the polarity of the rotaxanes such that they can be driven across the pump cassette and onto a strand.
Some potential applications of this technology include power storage and sequence-specific polymer construction. Polyrotaxane threads can be bound together to create a mesh, which may lead to scratch resistant or self-healing materials.
These molecular pumps can work in suspension, but there may be advantages to mounting them onto a surface.
Validation of the molecular pump operation is done using nuclear magnetic resonance or mass spectrometry.