2016 Chemistry Nobel Prize Winners

2016 Chemistry Nobel Prize Winners

Mechanical Bonds and Molecular Machines 

Nicholas G. Norwitz ’18

Perhaps you have learned about covalent bonds, ionic bonds, hydrogen bonds, dipole interactions, and even van der Waal forces, but what about mechanical bonds? The 2016 Nobel Prize for chemistry was awarded to Jean-Pierre Sauvage, Sir J. Fraser Stoddart, and Bernard L. Feringa for their innovations using a this special molecular interaction. A mechanical bond forms when molecular architectures interlock, such as in catenane and rotaxane molecules. A catenane is a tiny organic chain link formed by interlocking of cyclic molecules called macrocycles. A rotaxane is composed of a dumbbell shaped molecule threading a macrocycle such that the macrocycle is stuck between the two ends of the dumbbell. By adapting and combining catenanes and rotaxanes, these three scientists have created a plethora of ingenious nanoinventions.

The laureates have created molecular microchips in which rotaxanes serve as the binary code. By asymmetrically modifying the shaft of the rotaxane, and with a proper command of redox chemistry, one can control how the macrocycle shuttles across the dumbbell. Thus, the position of the macrocycle with respect to the two sides of the dumbbell can represent 1s and 0s. Their chips are already smaller than white blood cells with a molecular RAM of 1011 bits per cm2. As an aside, these scientists have also invented a different method for encoding binary code that is based on double bond stereochemistry. They have been able to embed these molecules into plastics, creating material that is so efficient at storing information that, if its full potential were to be realized, we could code 1,125,000 gigabytes of memory onto a single CD (that is 240 years worth of music).

By adhering similarly modified rotaxanes to the surface of silicon nanoparticles, these chemical engineers have also created a controllable drug delivery system. The nanoparticle encapsulates a drug and is taken up by a cell. In response to a signal, the rotaxane’s macrocycle shuttles across the rotaxane and causes the silicon shell to spill its contents. They have also designed other “smart pharmaceuticals” that could protect your microbiome and even help prevent bacterial antibiotic resistance. These drugs are only active when exposed to light. Thus, a person can take the inert drug and use a laser to active it at a specific time and location. Therefore, the drug would not harm your body’s normal flora and the drug would be inactive when it eventually gets into the environment, reducing bacterial exposure and antibiotic resistance.

These remarkable inventions hint at the potential of nanoinnovation. This award has only just been bestowed and already we have 2nm cars small enough to drive along a double strand DNA. It’s certainly an exciting time to be a chemist. However, there is one bit of bad news… this is what you have to do if you want to win a Nobel Prize.

 

For more information, here are some links to the 2016 Nobel Prize Chemistry Lectures:

https://www.nobelprize.org/nobel_prizes/chemistry/laureates/2016/sauvage-lecture.html

https://www.nobelprize.org/nobel_prizes/chemistry/laureates/2016/stoddart-lecture.html

https://www.nobelprize.org/nobel_prizes/chemistry/laureates/2016/feringa-lecture.html