ATmega328-Based Smartwatch Keeps Track Of Drugs In Your System by Analyzing Your Sweat

Wearables have been part of the medical field for a while now, making the work of medical practitioners easier. They help monitor heart rate, temperature, oxygen levels etc. However, to achieve the mission of personalized medicine, centering on delivering the right drug to the right patient at the right dose, therapeutic drug monitoring solutions are necessary. This has moved engineers from the UCLA Samueli School of Engineering and the Stanford School of Medicine to develop a smartwatch capable of tracking a wearer’s metabolization of medicines, by analyzing their sweat. About the smartwatch, Assistant Professor Sam Emaminejad who is the study lead says :

“We wanted to create a wearable technology that can track the profile of medication inside the body continuously and non-invasively…This way, we can tailor the optimal dosage and timing of the intake for each individual. And using this personalization approach, we can improve the efficacy of the therapeutic treatments.”

The engineers devised a surface engineering strategy, which enabled them to create a voltammetric sensing interface, featuring an “undistorted potential window,” within which the target electroactive drug’s voltammetric response is dominant and interference is eliminated, rendering reliable target quantification in noninvasively retrievable biofluids (sweat and saliva).

“Leveraging this sensing interface, a fully integrated, wearable solution was constructed to seamlessly render drug readouts with minute-level temporal resolution. To inform its clinical utility, the solution was utilized to demonstrate noninvasive pharmacokinetic monitoring of a pharmaceutical (here, acetaminophen, a widely used analgesic and antipyretic) in a wearable format.”

The smartwatch features an on-board LCD panel for live monitoring and a Bluetooth connection that transmits to an external data capture system for later analysis. At the core of the smartwatch is a Microchip ATmega328-based microcontroller which is connected to a 16-bit Texas Instrument DAC8552 digital-to-analog converter. It also features a Linear Technology LT1462 transfer impedance amplifier, a TI 12-bit ADS1015 analog-to-digital converter, and a Wurth Electronik AMB2621 Bluetooth module for communication. The smartwatch takes advantage of the small molecular structure of many drugs, which enables them to be present in our sweat. This enables the device to analyze the drug due to the quantities found in the sweat, and also detect how much of the drug is still circulating in the wearer’s system. The engineers carried out the test of the watch by tracking acetaminophen (an over-the-counter painkiller) over a short period, using a small electric current to force the wearer to sweat under the sensor.

About the smart watch, co-author Professor Ronald W. Davis says:

“This technology is a game-changer and a significant step forward for realizing personalized medicine.” He continues “Emerging pharmacogenomic solutions, which allow us to select drugs based on the genetic makeup of individuals, have already shown to be useful in improving the efficacy of treatments. So, in combination with our wearable solution, which helps us to optimize the drug dosages for each individual, we can now truly personalize our approaches to pharmacotherapy.”

We can find the full study which has been published under closed-access terms in the Proceedings of the National Academy of Sciences (PNAS) website.

Please follow and like us: