Non-Toxic Nanosubmarines to Deliver Drugs and Remove Toxic Chemicals

Summary: Rice University's Tour lab uses non-toxic nanosubmarines to deliver drugs and remove toxic chemicals, according to the ACS's Nano Letters Nov. 5, 2015.

Rice University scientists have created light-driven, single-molecule submersibles that contain just 244 atoms: Loïc Samuel/Rice University, no usage restrictions, via EurekAlert!

Tiny submersible vehicles with tiny propellers are capable of being built without employing or generating toxic chemicals, according to a paper published Nov. 5, 2015, in the monthly, peer-reviewed journal of the American Chemical Society, Nano Letters.

The study bases its findings upon the construction of nanosubmarines in the laboratory of James M. Tour, one of eight co-authors, professor of computer science and of materials science and nanoengineering, and T.T. and W.F. Chao Chair in Chemistry at Rice University in Houston, Texas.

Each non-toxic, one-molecule, pontoon-pushed, propeller-spun, 244-atom nanoscale submarine carries a microscopic motor. Each nanoscale motor depends upon a non-toxic power source, ultraviolet light, to spin at less than 1 inch (2.54 centimeters) per second.

Each microscopic motor emerges from a 20-step chemical synthesis elaborated in a doctoral thesis of 2009, Motors for Use in Molecular Nanotechnology, by Martin Klok for the department of molecular dynamics at the Stratingh Institute for Chemistry, University of Groningen, the Netherlands.

Each nanomotor finishes more than a million revolutions in a minute (RPM). The revolutions give the nanosubmarine power to move forward 18 nanometers per second in bacterial flagellum-like, whipping spins.

Dr. Tour holds that “These are the fastest-moving molecules ever seen in solution.” The speed is an accomplishment of motor-driven diffusing, or spreading out, since the co-researchers do not know yet how to steer the ultraviolet light-driven sub-10-nanometer submersibles through solutions of moving, same-sized molecules.

Dr. Tour judges that “This [navigation among moving molecules] is akin to a person walking across a basketball court with 1,000 people throwing basketballs at him.”

He knows from previous experimentation with molecular machines. The Tour lab leads with the pioneer production in 2005 of single-molecule, 3- to 4-nanometer-across nanocars, each with freely rotating axles, chassis, four buckyball (60-atom spheres of pure carbon) wheels and independently pivoting suspensions for driving across surfaces.

Victor García-López, lead article author and graduate student in the department of chemistry at Rice University, mentions that “These motors are well-known and used for different things. But we were the first ones to propose they can be used to propel nanocars and now submersibles.”

Non-toxic nanosubmarines need to deliver prescribed medicines by way of bloodstreams, remove toxic chemicals while ferrying water filters and undertake other conceptualized environmental and medical functions.

The confocal fluorescence microscope of Gufeng Wang, article co-author and North Carolina State University analytical chemist at Raleigh, offers performance-ready indications of proper four-step sequencing behind every revolution by tracking each nanosubmersible’s two pontoons red-fluorescing when subjected to laser and ultraviolet light while sandwiched between plates of diluted acetonitrile.

The experimental superiority of fast-spinning motor designs over non-motored, paddle-motor and slow-spinning designs prompts Victor García-López to state that “There’s a path forward. This is the first step, and we’ve proven the concept. Now we need to explore opportunities and potential applications.”

Rice graduate student Victor García-López holds a vial with millions of single-molecule nanosubmersibles. The nanosubs consist of 244 atoms and have motors that turn when activated by ultraviolet light: Jeff Fitlow/Rice University, no usage restrictions, via EurekAlert!

Acknowledgment

My special thanks to talented artists and photographers/concerned organizations who make their fine images available on the internet.

Image credits:

non-toxic nanosubmarines: Loïc Samuel/Rice University, no usage restrictions, via EurekAlert! @ http://www.eurekalert.org/multimedia/pub/103417.php?from=311881

Rice graduate student Victor García-López: Jeff Fitlow/Rice University, no usage restrictions, via EurekAlert! @ http://www.eurekalert.org/multimedia/pub/103419.php?from=311881

For further information:

Coldewey, Devin. 17 November 2015. "All Aboard: Single-Molecule Submarine Cruises the Atomic Seas." NBC News > Tech > Innovation.
Available @ http://www.nbcnews.com/tech/innovation/all-aboard-single-molecule-submarine-cruises-atomic-seas-n465106

García-López, Victor, et al. 5 November 2015. "Unimolecular Submersible Nanomachines. Synthesis, Actuation, and Monitoring." Nano Letters, vol. 15, issue 12: 8229-8239. DOI: 10.1021/acs.nanolett.5b03764
Available @ http://pubs.acs.org/doi/abs/10.1021/acs.nanolett.5b03764

Klok, Martin. 2009. Motors for Use in Molecular Nanotechnology. Department of Molecular Dynamics at the Stratingh Institute for Chemistry, University of Groningen, the Netherlands.

Nanotechnology @nanotechnology. 16 November 2015. "Rice makes light-driven nanosubmarine: (<i>Rice University<i>): Rice University scientists build nanoscale sub. . ." Twitter.
Available @ https://twitter.com/Nanotechnology/status/666307126227144705

Williams, Mike. 16 November 2015. "Rice Makes Light-Driven Nanosubmarine." Rice University News & Media > News Releases.
Available @ http://news.rice.edu/2015/11/16/rice-makes-light-driven-nanosubmarine/