Low-cost fiber-based electrochemical sensor for quantification of acetaminophen in human breast milk

Acetaminophen is the most common cause of acute liver failure in the United States. The transfer of drugs to breast milk poses risks to infants, yet dosing guidelines are based on limited data from small studies. Currently, drug levels in milk are simply estimated through invasive blood draws. We present a new low-cost, textile-based electrochemical sensor for detecting acetaminophen at the point of use in breast milk. An embroidered conductive yarn (steel and silver) is used, which eliminates the need for complex microfabrication processes. A gold-nanoparticle-doped carbon ink-modified steel yarn serves as the working electrode, with pristine steel and silver yarns as counter and reference electrodes, respectively. Using square wave voltammetry, the sensor achieves a linear detection range of 9.9–166.4 μM in undiluted breast milk, with a limit of detection of 1.15 μM. This platform provides a simple and accessible alternative for drug monitoring