High-precision micro-total analysis of sodium ions in breast milk

• Published in: Sensors and actuators. B, Chemical Chemical, 2025-01, Vol.422, p.136652, Article 136652
• Main Authors: Bao, Huilu, Fan, Xiao, Zhang, Xiaoyu, Zhang, Xin, Kivlighan, Katie T., Schneider, Sallie S., Liu, Jianghong, Johnson, Alan T. Charlie, Arcaro, Kathleen F., Ping, Jinglei
• Format: Article
• Language: English
• Subjects: Breast milk; Graphene; Ion-selective field-effect transistor; Lab on a chip; Micro electrodialysis; MicroTAS; Sodium ions
• ISSN: 0925-4005
• DOI: 10.1016/j.snb.2024.136652

Measuring sodium ion concentration in breast milk can provide crucial health information for both mother and infant, including early signs of low-grade infection and reduced milk supply. Traditional sensing methods are slow, bulky, expensive, and require skilled operators. Here, we develop a coverslip-sized, high-precision lab-on-a-chip device that processes and detects sodium ions in human breast milk. The device uses micro-electrodialysis to extract sodium ions into a simple acceptor solution with 92 ± 3 % efficiency and employs a graphene ion-selective sensor for high-performance quantification. We demonstrate a straightforward calibration strategy, enabling the device to measure breast-milk sodium ion levels in 141 seconds, with accuracy comparable to inductively coupled plasma mass spectrometry. Our approach offers a promising pathway to efficient, point-of-care diagnosis of conditions associated with metal-ion levels in complex liquid-biopsy samples. •Lab-on-chip device for detecting sodium ions in breast milk at lab-level accuracy.•Integration of micro electrodialysis with graphene-based biosensing.•High-efficiency isolation and high-sensitivity quantification of sodium ions.