When Science Sings: How music can inspire new tools

(Written as part of my application to MIT's Science Journalism Master's Program in 2019)

Have you ever wondered what NyQuil sounds like? What do you think you would hear if you plucked a string of Pepto Bismol?

Thanks to the efforts of a group of researchers at the University of California, Riverside you can now hear the music behind a molecule. Inspired by an ancient musical instrument from Africa, scientists describe in a recent paper how they transformed a thumb piano, or mbira, into a precise scientific instrument capable of distinguishing between pure and counterfeit medicine.

By replacing the tines of the mbira with a thin tube, the researchers developed a way to load small amounts of drug samples into the instrument without changing how it is played. By filling the tube with a sample drug, strumming the filled tube as if it were a normal tine, recording the tone it produces and comparing it to that produced by the pure drug, they can easily and quickly identify phony drugs. If the tone matches, the drug is real. If not, the drug might be counterfeit and could have fatal consequences if ingested.

Excerpt of figure 1 from study.

The sound from the mbira, and every instrument, is created by vibrations. Instruments transform the vibrations you produce by plucking the strings on a guitar, blowing across a reed in a clarinet, or buzzing your lips to play a trumpet, to create sound. The mbira tines are of varying lengths which when flicked vibrate at different frequencies and produce different pitches you then use to create music. Using the researchers’ mbira, you flick a sample-filled tube instead of a tine. The vibrations travel through the sample and, depending on its density, will produce different frequencies of sound. If you have a good ear you can distinguish between similar frequencies, but just in case you failed music class the authors of the study developed a smartphone application to help. Strike the metal tube a few times as the application listens and records the tone. After a bit of calibration by recording the tones of known substances the app translates the unknown sample into a density reading.

While it’s easy to see the difference between a guitar and a piano, distinguishing between two similar chemicals is oftentimes impossible without specialized equipment and trained personnel to make sense of the readout. Particularly in developing countries and rural communities already plagued with increased incidences of drug tampering, such analysis tools are scarce and difficult to use. However, with the modified mbira, anyone can easily determine the density of an unknown sample quickly and accurately.

The beauty of the instrument is in its simplicity. A drug-deciphering mbira can be constructed with scrap material so long as the main components: the tubing, a fastener for the tube and the base, are present. The researchers compared a home-made mbira constructed with scrap material from the lead scientist’s home garage with a mbira constructed in the lab and found no significant differences between the two.

The simple design of the mbira also makes it easily customizable depending on the needs of the practitioner. For example, just like as with the normal mbira with tines of different lengths, the length of the sample tube can be altered thereby expanding the range of densities that can be measured.

But the implications of this work reach beyond measuring the density of a chemical. The mbira created in this study is just one example of how a relatively simple tool can be refashioned into a life-saving sensor. In the age of vast technological advancement some of the most creative and useful tools are those inspired by centuries old objects.

Source article: Grover, W.H. et al. “Musical Instruments as Sensors.” ACS Omega. 2018.