Zhou Xingcheng, Slaughter Jessica, Riki Smah, Kuo Chao Chi, Furst Ariel
Department of Chemical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Ave, Cambridge, Massachusetts 02139, United States.
Center for Environmental Health Sciences, Massachusetts Institute of Technology, 77 Massachusetts Ave, Cambridge, Massachusetts 02139, United States.
ACS Sens. 2025 Jul 25;10(7):5019-5026. doi: 10.1021/acssensors.5c00937. Epub 2025 Jun 30.
As healthcare systems worldwide demand early disease detection and personalized medicine, electrochemical biosensors stand out as a promising technology to meet these demands due to their sensitivity, selectivity, and rapid response. Specifically, DNA-based electrochemical biosensors are versatile and have been used to identify biomarkers of various infectious diseases. However, there is a significant gap between laboratory-scale proof-of-concept systems and commercially viable technologies. Commercialization of such sensors faces many challenges, with one of the most important being the stability and shelf life of the immobilized DNA. Surface-associated DNA faces thermal degradation, structural changes, and oxidation of tethering thiol groups, which causes DNA stripping from the surface. Currently, technology to support the long-term storage of these sensors at ambient temperatures is limited. Here, we report a novel method to preserve DNA in electrochemical biosensors through the application of a protective coating of poly(vinyl alcohol) (PVA). We show that with our PVA coating, the shelf life of dried, DNA-functionalized electrodes at ambient temperature is a minimum of 2 months. We further demonstrate that the protective capabilities of PVA extend to temperatures as high as 65 °C and that the biological relevance of the assay is not impacted by the coating. Our simple approach to DNA protection supports our understanding of how the electrode interfaces with biomolecules and facilitates biosensor scaling and commercialization.
随着全球医疗保健系统对早期疾病检测和个性化医疗的需求不断增加，电化学生物传感器因其灵敏度、选择性和快速响应能力脱颖而出，成为满足这些需求的一项很有前景的技术。具体而言，基于DNA的电化学生物传感器用途广泛，已被用于识别各种传染病的生物标志物。然而，实验室规模的概念验证系统与具有商业可行性的技术之间存在显著差距。此类传感器的商业化面临诸多挑战，其中最重要的挑战之一是固定化DNA的稳定性和保质期。与表面相关的DNA会面临热降解、结构变化以及连接硫醇基团的氧化，这些都会导致DNA从表面剥离。目前，支持这些传感器在环境温度下长期储存的技术有限。在此，我们报告一种通过应用聚乙烯醇（PVA）保护涂层来保存电化学生物传感器中DNA的新方法。我们表明，使用我们的PVA涂层，在环境温度下干燥的、DNA功能化电极的保质期至少为2个月。我们进一步证明，PVA的保护能力可延伸至高达65°C的温度，并且该检测方法的生物学相关性不受涂层影响。我们这种简单的DNA保护方法有助于我们理解电极与生物分子的界面作用，并促进生物传感器的规模化生产和商业化。
