How does your computer smell?

January 13, 2021

A keen sense of smell is a powerful ability shared by many organisms. However, it has proven difficult to replicate by artificial means. Researchers combined biological and engineered elements to create what is known as a biohybrid component. Their volatile organic compound sensor can effectively detect odors in gaseous form. They hope to refine the concept for use in medical diagnosis and the detection of hazardous materials.

Electronic devices such as cameras, microphones and pressure sensors enable machines to sense and quantify their environments optically, acoustically and physically. Our sense of smell however, despite being one of nature's most primal senses, has proven very difficult to replicate artificially. Evolution has refined this sense over millions of years and researchers are working hard to catch up.

"Odors, airborne chemical signatures, can carry useful information about environments or samples under investigation. However, this information is not harnessed well due to a lack of sensors with sufficient sensitivity and selectivity," said Professor Shoji Takeuchi from the Biohybrid Systems Laboratory at the University of Tokyo. "On the other hand, biological organisms use odor information extremely efficiently. So we decided to combine existing biological sensors directly with artificial systems to create highly sensitive volatile organic compound (VOC) sensors. We call these biohybrid sensors."

Takeuchi and his team essentially grafted a set of olfactory receptors from an insect into a device that feeds certain odors to the receptors and also reads how the receptors respond to these odors. Analysis of electrical signals from the olfactory receptors indicates what molecules triggered the signals. This method yields great sensitivity and is possible thanks to the way the receptors are physically bound within lipid bilayers. In previous experiments such a method has limited the way odors can be delivered to the receptors, but the team created an efficient solution to this problem too.

"The receptors react to molecules in a liquid droplet, so one of the main challenges was to make a device to transplant molecules from their air into these droplets," said Takeuchi. "We designed and fabricated microscale slits underneath where the droplet passes to force this exchange of molecules. By introducing the gas into the microslit, we were able to increase the probability of contact between the gas and the droplet and transfer target molecules to the fluid efficiently."

With this system, the researchers were able to detect traces of the chemical octenol, also called mushroom alcohol, which is known to attract mosquitoes, in the breath of a test subject. Not only that but the VOC sensor could detect concentrations on the order of parts per billion. This is about a thousand times less than the sensitivity of a dog's nose but it is an impressive achievement nonetheless and has inspired the team to keep innovating.

"I would like to expand upon the analytical side of the system by using some kind of AI. This could enable our biohybrid sensors to detect more complex kinds of molecules," said Takeuchi. "Such refinements might help in our goals to not only measure hazardous materials and environmental hazards but maybe even early stages of diseases from patients' breath and body odor."
-end-
Journal article

Tetsuya Yamada, Hirotaka Sugiura, Hisatoshi Mimura, Koki Kamiya, Toshihisa Osaki and Shoji Takeuchi. Highly sensitive VOC detectors using insect olfactory receptors reconstituted into lipid bilayers. Science Advances. DOI: 10.1126/sciadv.abd2013.

https://advances.sciencemag.org/lookup/doi/10.1126/sciadv.abd2013

Funding

This study is partly supported by the New Energy and Industrial Technology Development Organization (NEDO), Japan, by JSPS KAKENHI Grant Number JP16H06329, by the Program for Building Regional Innovation Ecosystem of MEXT, Japan.

Useful links

Biohybrid Systems Laboratory
http://www.hybrid.t.u-tokyo.ac.jp/en/

Institute of Industrial Science
https://www.iis.u-tokyo.ac.jp/en/

Department of Mechano-Informatics
https://www.i.u-tokyo.ac.jp/edu/course/m-i/index_e.shtml

International Research Center for Neurointelligence
https://ircn.jp/en/

Video on previous research
https://youtu.be/RMW_JJTOnUE

Research Contact

Professor Shoji Takeuchi
(1) Graduate School of Information Science and Technology, The University of Tokyo
7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656
Tel: +81-3-5841-6488

(2) Institute for Industrial Science
4-6-1 Komaba, Meguro-ku, Tokyo 153-8505
Tel: +81-3-5452-6650 - Email: takeuchi@hybrid.t.u-tokyo.ac.jp

Press Contact

Mr. Rohan Mehra
Division for Strategic Public Relations, The University of Tokyo
7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8654, JAPAN
Tel: +81-3-5841-0876 - Email: press-releases.adm@gs.mail.u-tokyo.ac.jp

About the University of Tokyo

The University of Tokyo is Japan's leading university and one of the world's top research universities. The vast research output of some 6,000 researchers is published in the world's top journals across the arts and sciences. Our vibrant student body of around 15,000 undergraduate and 15,000 graduate students includes over 4,000 international students. Find out more at http://www.u-tokyo.ac.jp/en/ or follow us on Twitter at @UTokyo_News_en.

University of Tokyo

Related Molecules Articles from Brightsurf:

Finally, a way to see molecules 'wobble'
Researchers at the University of Rochester and the Fresnel Institute in France have found a way to visualize those molecules in even greater detail, showing their position and orientation in 3D, and even how they wobble and oscillate.

Water molecules are gold for nanocatalysis
Nanocatalysts made of gold nanoparticles dispersed on metal oxides are very promising for the industrial, selective oxidation of compounds, including alcohols, into valuable chemicals.

Water molecules dance in three
An international team of scientists has been able to shed new light on the properties of water at the molecular level.

How molecules self-assemble into superstructures
Most technical functional units are built bit by bit according to a well-designed construction plan.

Breaking down stubborn molecules
Seawater is more than just saltwater. The ocean is a veritable soup of chemicals.

Shaping the rings of molecules
Canadian chemists discover a natural process to control the shape of 'macrocycles,' molecules of large rings of atoms, for use in pharmaceuticals and electronics.

The mysterious movement of water molecules
Water is all around us and essential for life. Nevertheless, research into its behaviour at the atomic level -- above all how it interacts with surfaces -- is thin on the ground.

Spectroscopy: A fine sense for molecules
Scientists at the Laboratory for Attosecond Physics have developed a unique laser technology for the analysis of the molecular composition of biological samples.

Looking at the good vibes of molecules
Label-free dynamic detection of biomolecules is a major challenge in live-cell microscopy.

Colliding molecules and antiparticles
A study by Marcos Barp and Felipe Arretche from Brazil published in EPJ D shows a model of the interaction between positrons and simple molecules that is in good agreement with experimental results.

Read More: Molecules News and Molecules Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.