Bacterial vaginosis (BV) is the most frequently occurring vaginal infection worldwide, yet it remains significantly underdiagnosed as a majority of patients are asymptomatic. Untreated BV poses a serious threat as it increases one’s risk of STI acquisition, pregnancy complications, and infertility. We aim to minimize these risks by creating a low-cost disposable sensor for at-home BV diagnosis. A clinical diagnosis of BV is most commonly made according to the Amsel criteria. In this method, a fish-like odor, caused by increased levels of trimethylamine (TMA) in vaginal fluid, is used as a key diagnostic. This paper outlines the development of a Home-Based Electrochemical Rapid Sensor (HERS), capable of detecting TMA in simulated vaginal fluid (sVF). Instead of odor-based detection of volatilized TMA, we identify TMA in trimethylammonium form by utilizing HERS and a potentiometric readout. We fabricated the ion selective electrode using a carbon-black-coated cotton string and a TMA-selective membrane consisting of calix[4]arene and sodium tetrakis[3,5-bis(trifluoromethyl)phenyl]borate. When paired with a standard reference electrode, our device was able to quantify TMA concentration in deionized (DI) water, as well as sVF samples at multiple pH levels with a clinically relevant limit of detection (8.66 µM, and theoretically expected Nernstian slope of 55.14 mV/decade).

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

Mastitis occurs when blocked milk ducts lead to inflammation of the breast tissue and can cause significant discomfort for breastfeeding mothers. A key biomarker for mastitis is the altered sodium‐to‐potassium (Na ⁺ /K ⁺ ) ratio in breast milk due to tight junction dysfunction. In this work, MAMAWEL is introduced, the first potentiometric sensor designed for at‐home mastitis diagnosis. This device integrates Na ⁺ and K ⁺ sensors with an ionic‐liquid‐based reference electrode, enabling early detection of mastitis before clinical symptoms arise. To ensure reliable, calibration‐free operation, 2,2,6,6‐tetramethylpiperidinyloxy (TEMPO) is incorporated, a redox buffer that establishes a thermodynamically controlled interface, enhancing sensor reproducibility. Comparative analysis with commercially available sensors demonstrates that MAMAWEL effectively differentiates between healthy and mastitis‐affected milk samples, achieving a concentration estimation error margin of less than 10%. Designed for both wearable and point‐of‐care applications, MAMAWEL has the potential to transform early mastitis detection, reducing maternal discomfort and promoting breastfeeding health.