There’s Power In Your Spit: Biobatteries And What A Little Saliva Can Do



There’s been some buzz about the development of a new generation of batteries that run on biological agents such as bacteria and body fluids like saliva. Termed “Biobatteries”, these devices have not gained widespread use because of their complex nature and lack of efficiency. At best, they were used for low power electronics on a very esoteric basis.

Bring on Binghamton Group’s new generation of microbial fuel cells, or MFC’s as they are called. The company has simplified the operation and accessibility of the technology down to the use of a single sheet of paper and freeze-dried bacteria that are activated by nothing other than a little spit…yes, your saliva.

Paper thin chip

An incredible leap from licking a postage stamp (which even predates the 90’s generation), these little pieces of paper can actually be used to power different types of sensors and other low power electronics. The applications look promising for powering diagnostic sensors that could detect HIV, cancer, and monitor glucose levels…I’m thinking of numerous applications as I write this like colon testing, blood vessel testing, who knows but the field of bio-electronics is about to explodewith this higher level of accessibility.

underdeveloped nations


This could mean a lot in bringing this technology to developing countries and unleashing a level of sophistication in medical care and wellness previously unknown to impoverished and remote areas of the world.

Having readily available devices that are made of common materials that could be manufactured globally or even shipped easily to remote parts of the world and other areas without adequate medical facilities or electricity. Satellite and other operations in space would qualify.


Choi’s work is part of the growing and important field of papertronics. (Binghamton University) Aaron Mazzeo, an assistant professor of mechanical and aerospace engineering at Rutgers, makes papertronics for flexible human-machine interfaces—things like wearable paper devices to monitor sweat for cortisol, an indicator of stress.

A battery like Choi’s could be the power source he needs.

“We are going to continue to have the ongoing challenge of providing power to these devices,” says Mazzeo. “Having the electrical power allows you to do the diagnosis, but it could also potentially amplify the signals, so you might be able to detect smaller quantities. This is way out in the future, but this type of thing could be useful for not only measuring cortisol, but maybe even things like cholesterol or alcohol or other clinically relevant markers in the blood, urine or sweat.”


Both Mazzeo’s and Choi’s work is part of the growing and important field of papertronics and bioavailable battery design.


urine powered batteries


MFC technology is not entirely new. As described in the journal Applied Energy, previous studies were done with urine as the biofluid catalyst to generate power, however, the model showed the ability of a battery to be sufficiently powered to charge a Samsung phone only partially with 600 milliliters of urine and a full charge would take about 4.2 liters of urine.

Not too practical, (and not too portable) but the research showed promise, and was one of the first to use a stacking technique of MFC’s one on top of another to amplify the amount of energy generated.

Urine powered MFC has had some success in commercial applications which have been used efficiently with very small sensor electronics such as home pregnancy tests.

In all fairness, urine has been shown in several studies to be a viable biofuel for generating electricity in sanitary models contructed using a public structure such as an airport, mall, or expo center to route urine from restrooms through an MFC system to produce electricity for the building that would power small LED lights.



Origami papertronics


Of course the future testing and research will address how to improve the design and function of these bio-batteries.

The greatest challenge is how to make them more powerful and efficient. This challenge is already being spearheaded by Choi’s research along with his students in finding ways to stack the paper cells together to make them more powerful as a group. To do this, they are employing the ancient art of Origami.

“Building on Choi’s initial finding that stringing several biobatteries together made them perform better, the team found that when stacking them on a single sheet of folded paper, power increased exponentially.

In peer-reviewed journals Choi and his research team showed how microbial fuel cells embedded in a paper origami matchbook, and later, pressed into a flat, transforming ninja star, were the most simple, biodegradable and inexpensive ways to generate the kind of electricity needed to power simple and more sophisticated diagnostic biosensors in the field.

Compared to traditional batteries, they are not only easy to transport but are also exponentially cheaper to produce.”

Read more about the ongoing work of Origami biobatteries here.

It’s amazing and humbling to think that a marriage of frontier technology and an ancient Chinese art create the perfect model for this micro-sized energy powerhouse.


environmentally friendly remote area


A further observation by Rachel Crowell on Rewire is that the environmental and economic footprint of these devices is very small.

Choi’s batteries are cheap to make: one battery costs just 10 cents to manufacture. Choi thinks it will be possible to bring this cost down even more with future work. And these batteries could also be mass-produced.

The batteries are also environmentally-friendly, he said. They’re powered by one of the most renewable resources of them all—germs. Many different kinds of bacteria can fuel them, including the ones living in local wastewater.

This is a complete gamechanger, since no specific source of biologic material is required, and bacteria abound in most environments globally.

Papertronics can also bring a newer dimension to bioelectronics that isn’t available in non-electrical types of sensors. Most chemically dependant sensors used commercially that don’t employ electricity, such as urine tests for bacterial infection or acidity and current home pregnamcy tests allow for a simple ‘positive’ or ‘negative’ result by sensing the presence of a hormone or other chemical.






However, employing electricity in these single and multilayer paper battery cells could provide the accuracy to specifically measure glucose levels, and even alcohol and cortisol levels with just a paper cell, no other machines or electrical devices required.

Choi and his team are focused on the functional aspect of their future inventions rather than rushing to commercialization of the technology. They are moving forward with further research that will hopefully provide wearable devices for monitoring different aspects of human performance.

There are so many avenues this new technology promises to open for better and accessible healthcare for near future generations. If you would like to follow the latest news on these innovations, watch the following video on Binghamton University’s Youtube channel:


Add a Comment

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.