The Tool Desk
Outbyte Driver Updater FREEScan for outdated or missing drivers - takes under a minuteDriver Scan →Outbyte PC Repair FREERepair Windows errors before they cause bigger problemsFix Now →iTechGuides is reader-supported. When you buy through links on our site, we may earn an affiliate commission. As an Amazon Associate I earn from qualifying purchases. Learn more
A catalytic molecular rotor can be switched on and off by chemical signals inside a molecular network—not by a person steering it from a distance. In the system reported by Michael Schmittel and colleagues at the University of Siegen, adding zinc(II) prompts copper(I) ions to move between components, assembling a rotor that catalyses a model reaction. Removing zinc(II) reverses the transfer and disassembles the active structure.
What “remote control” means at the molecular scale
Here, remote control is chemical communication among molecules in a mixture. One component responds to a chemical input and passes on a signal through ion transfer. That chain of events changes the structure and activity of another component; there is no miniature robot, radio link, or mechanical operator.
The report describes an eight-component network built around two copper-loaded nanoswitches and a weakly coordinated precursor associated with a rotator molecule. The rotator has two pyridyl terminals. The components are arranged so that a zinc(II) input can trigger copper(I) movement and bring the catalytic structure together.
How the chemical signal assembles the rotor
- Add zinc(II): the signal prompts the two nanoswitches to transfer copper(I) ions to the precursor.
- Complete the rotor: the copper(I) ions coordinate at phenanthroline sites, assembling the catalytically active three-component nanorotor.
- Enable motion: the free end of the rotator can coordinate weakly at the copper sites and exchange between them. That exchange produces rotor motion.
The important distinction is that the system’s moving part and catalytic function are enabled by the same assembly process. Copper(I) transfer does not merely make the structure move; it also establishes the copper sites needed for the reported catalytic activity.
#1 Best Overall
How the researchers tested catalytic switching
The researchers used a model click reaction to test whether the assembled rotor had catalytic function. The report says the reaction was catalysed only after the nanorotor assembled. It gives no numerical reaction rate or yield, so the result supports qualitative switching—not a quantified performance claim.
| State | Copper(I) arrangement | Reported catalytic behavior |
|---|---|---|
| Assembled | Copper(I) is coordinated at the precursor’s phenanthroline sites. | The nanorotor catalyses the model click reaction. |
| Disassembled | Copper(I) returns to the nanoswitches. | The resulting ensemble is catalytically inactive in the reported test. |
How the rotor is switched off
The reverse sequence begins with hexcyclen, which removes zinc(II). Copper(I) then returns to the nanoswitches as the rotor disassembles. The network is left in a catalytically inactive ensemble, reversing the activation associated with the assembled state.
Why coordinating the components was difficult
A multi-component network can miscommunicate: a molecule or ion may interact with the wrong component or interfere with a desired transfer. Schmittel said the challenge was to create selective ion-transfer schemes without interference, while also harmonizing the transfer time with the catalytic reaction rate and optimizing the substrates and solvent mixture. As he put it, “The larger the number of components, the more difficult interference-free communication is within the network,” in Chemistry World’s report.
Free tools Windows power users keep installed
One-click scans. No signup required.
Schmittel framed the broader research direction this way: “The time has come to soar above stand-alone molecular devices and to realise functions not in defined molecules but in complex networks, as ingeniously demonstrated in biological systems.”
What the work suggests—and what it does not show
Matthieu Raynal, a supramolecular chemist at Sorbonne University, said: “This work nicely illustrates how self-assembly enables the formation of intricate, yet well-defined, functional molecular systems,” in the same report. He pointed to switchable catalysts and interconnected catalysts for cascade reactions as possible directions. Those are prospective ideas, not applications demonstrated by this nanomachine.
The report concerns a research system, not a consumer device or commercially available nanomachine. It establishes a chemical trigger, reversible assembly, rotor motion, and qualitative catalytic switching in a model reaction. It does not report a practical deployment, numerical reaction yield or rate, or quantified cycle time.
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.Source and publication
The system was reported by Colin King in Chemistry World on 3 May 2018. The report cites A. Goswami, S. Pramanik and M. Schmittel, Chemical Communications, 2018, volume 54, page 3955, DOI 10.1039/C8CC01496E. Read the Chemistry World report.
Quick wins for a faster PC:
Fix the driver behind crashes, sound loss and screen glitchesFind Drivers →Clear out junk files and repair common Windows errorsFree Scan →Quick Recap
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
