Teen prints a device to help keep wounds dry | Science News for Students

Teen prints a device to help keep wounds dry

Made of carbon particles printed on paper, sensor detects when a bandage gets wet
Nov 18, 2016 — 7:00 am EST
Anushka Naiknaware

Anushka Naiknaware (center) works on a project with other members of her team at the 2016 Broadcom MASTERS. Team members from left: Rachel Pizzolato, Nathan Deng, Lucas Ritzdorf and Aria Eppinger.

L. Doane/SSP

WASHINGTON, D.C. — When you get a cut or blister, you cover it with a bandage. How do you know when to change it? Maybe you just wait until it’s wet or dirty. But when people have long-term — or chronic — wounds that take months to heal, changing bandages too early or too late could make healing take even longer. When Anushka Naiknaware, 13, learned about chronic wounds, she decided to make a device that could alert a person when it’s time to change their bandage. Her invention required tiny particles of carbon, a smartphone — and her home printer. 

Anushka is a student at Stoller Middle School in Portland, Ore. Her invention brought her to the 2016 Broadcom MASTERS competition, where she won first place in mathematics. MASTERS stands for Math, Applied Science, Technology and Engineering for Rising Stars. Created by Society for Science & the Public and sponsored by the Broadcom Foundation, the yearly event brings 30 middle-school students together from around the country to show off their award-winning science fair projects. (Society for Science & the Public also publishes Science News for Students and this blog.)

Chronic wounds are wounds such as ulcers — or open sores — that take longer than three months to heal. These wounds are common in people who are older or who have certain conditions, such as diabetes. Chronic wounds affect around 6.5 million people per year in the United States. With so many people suffering from them, Anushka wondered, “what is this…and why has no one addressed it yet?”

Changing the dressing on a wound too often can provide an opportunity for infections to sneak in. But if a bandage gets very moist very quickly from the inside, it might be filling with pus — a sign an infection has begun. Judging just when to change a bandage is important. Anushka decided to develop a device to guide this timing.   

The invention needed to be sensitive to moisture — but not too sensitive. It had to be something that wouldn’t irritate the wound or the person’s skin. And it should probably be cheap.

After a lot of trial and error, the teen settled on a design that used an “ink” filled with carbon nanoparticles. These are tiny spheres of carbon atoms. They are conductive — they allow an electric current to flow. And when they are printed onto paper in a line and connected at each end with copper wires, electricity from a battery can flow along the line from wire to wire. But this flow changes when the nanoparticles get wet.

wound sensor
Anushka shows where her sensor would go inside a bandage.
B. Brookshire/SSP

Anushka made an artificial “pus” out of acetic acid and water, and dripped it on some nanoparticles. She found the pus increased resistance. The electricity could not flow as well.

To get the carbon nanoparticles into a bandage, the teen mixed them into an ink to print onto paper. But first, she treated the paper with a chemical called chitosan.  Chitosan is a chemical from the shells of shrimp. It prevents bacteria from growing and helps to stop bleeding. It is added to some bandages to help blood clot faster.

The teen loaded her ink into a printer cartridge to print onto her special paper. Well, actually, Anushka loaded her ink into many, many printer cartridges. Just changing a printer cartridge isn’t easy, and filling one is even harder. “Messy is an understatement,” she says. “I’ve jammed printers. I’ve jammed ink cartridges.… I did all this at home. My carpet used to be white. Now it’s stained gray from carbon nanoparticles.”

Anushka hooked up the printed carbon nanoparticle patterns and copper wires to a Bluetooth sensor. The sensor measured resistance and could transmit the information over short distances. She then placed the sensor inside a bandage. If moisture within the bandage gets too high, and resistance goes up, an alert goes off. The teen designed two versions — one that lights up a tiny light, and another that sends an alert to a smartphone.

The small printed papers cost only five to 10 cents, Anushka estimates. The Bluetooth sensor is more expensive, but the teen notes that it could be used over and over again. She also knows there’s a long way to go before her design can help patients. It hasn’t even been tested on a real person yet. “You have to make sure everything works perfectly,” she says. “I want to see this project to the end, but there’s a lot of intervening work that has to be done.”

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Power Words

acetic acid  A clear acid that is found in vinegar. It’s used to make products such as rubber, plastics, paints and dyes.

atom     The basic unit of a chemical element. Atoms are made up of a dense nucleus that contains positively charged protons and neutrally charged neutrons. The nucleus is orbited by a cloud of negatively charged electrons.

battery     A device that can convert chemical energy into electrical energy.

Bluetooth  A wireless technology that transmits data over short distances (usually around one meter or 3.3 feet).

blog     Short for web log, these Internet posts can take the form of news reports, topical discussions, opinionated rants, diaries or photo galleries.

Broadcom MASTERS     Created and run by the Society for Science & the Public, Broadcom MASTERS (Math, Applied Science, Technology and Engineering Rising Stars) is the premier middle school science and engineering fair competition. Broadcom MASTERS International gives select middle school students from around the world a unique opportunity to attend the Intel International Science & Engineering Fair.

carbon     The chemical element having the atomic number 6. It is the physical basis of all life on Earth. Carbon exists freely as graphite and diamond. It is an important part of coal, limestone and petroleum, and is capable of self-bonding, chemically, to form an enormous number of chemically, biologically and commercially important molecules.

chronic     A condition, such as an illness (or its symptoms, including pain), that lasts for a long time.

conductive     Able to carry an electric current.

copper     A metallic chemical element in the same family as silver and gold. Because it is a good conductor of electricity, it is widely used in electronic devices.

current     A fluid body — such as of water or air — that moves in a recognizable direction. (in electricity) The flow of electricity or the amount of electricity moving through some point over a particular period of time.

develop     (as with towns) The conversion of wildland to host communities of people. This development can include the building of roads, homes, stores, schools and more. Usually, trees and grasslands are cut down and replaced with structures or landscaped yards and parks.

diabetes     A disease where the body either makes too little of the hormone insulin (known as type 1 disease) or ignores the presence of too much insulin when it is present (known as type 2 diabetes).

electric current     A flow of charge, called electricity, usually from the movement of negatively charged particles, called electrons.

electricity     A flow of charge, usually from the movement of negatively charged particles, called electrons.

error     (In statistics) The non-deterministic (random) part of the relationship between two or more variables.

infection     A disease that can spread from one organism to another. It’s usually caused by some sort of germ.

information     (as opposed to data) Facts provided or trends learned about something or someone, often as a result of studying data.

middle school     A designation for grades six through eight in the U.S. educational system. It comes immediately prior to high school. Some school systems break their age groups slightly different, including sixth grade as part of elementary school and then referring to grades seven and eight as “junior” high school.

moisture     Small amounts of water present in the air, as vapor. It can also be present as a liquid, such as water droplets condensed on the inside of a window, or dampness present in clothing or soil.

molecule     An electrically neutral group of atoms that represents the smallest possible amount of a chemical compound. Molecules can be made of single types of atoms or of different types. For example, the oxygen in the air is made of two oxygen atoms (O2), but water is made of two hydrogen atoms and one oxygen atom (H2O).

nanoparticle     A small particle with dimensions measured in billionths of a meter.

particle     A minute amount of something.

resistance     (as in drug resistance) The reduction in the effectiveness of a drug to cure a disease, usually a microbial infection. (as in disease resistance) The ability of an organism to fight off disease. (as in exercise) A type of rather sedentary exercise that relies on the contraction of muscles to build strength in localized tissues. (in physics) Something that keeps a physical material (such as a block of wood, flow of water or air) from moving freely, usually because it provides friction to impede its motion.

sensor     A device that picks up information on physical or chemical conditions — such as temperature, barometric pressure, salinity, humidity, pH, light intensity or radiation — and stores or broadcasts that information. Scientists and engineers often rely on sensors to inform them of conditions that may change over time or that exist far from where a researcher can measure them directly. (in biology) The structure that an organism uses to sense attributes of its environment, such as heat, winds, chemicals, moisture, trauma or an attack by predators.

smartphone     A cell (or mobile) phone that can perform a host of functions, including search for information on the Internet.

society     An integrated group of people or animals that generally cooperate and support one another for the greater good of them all.

Society for Science & the Public  (or SSP ) A nonprofit organization created in 1921 and based in Washington, D.C. Since its founding, SSP has been not only promoting public engagement in scientific research but also the public understanding of science. It created and continues to run three renowned science competitions: The Regeneron Science Talent Search (begun in 1942), the Intel International Science and Engineering Fair (initially launched in 1950) and Broadcom MASTERS (created in 2010). SSP also publishes award-winning journalism: in Science News (launched in 1922) and Science News for Students (created in 2003). Those magazines also host a series of blogs (including Eureka! Lab).

solution     A liquid in which one chemical has been dissolved into another.

transmit     To send or pass along.

ulcer  An inflamed sore on the skin or on a mucous membrane such as inside the mouth or in the stomach.


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