Noninvasive Point-of-Care Testing: From Sensing Technologies and Wearable Platforms to Intelligent Diagnostics

Point-of-care testing (POCT) represents a significant innovation in healthcare diagnostics, driving the evolution of clinical practice and health management toward greater convenience and personalization. However, conventional invasive POCT techniques are constrained by patient discomfort, infection risk, and discontinuous monitoring inherent to blood sampling, thereby limiting their utility for the long-term management of chronic diseases and personalized health monitoring. To overcome these limitations, noninvasive POCT technologies have emerged. These platforms enable painless and continuous monitoring by detecting biomarkers in easily accessible biofluids, such as saliva, sweat, and tears. This review systematically summarizes recent advancements in noninvasive POCT, with a focus on the operational principles, representative applications, and developmental trends of electrochemical and optical sensing modalities. We also examine progress in the integration of these sensors with microfluidics and flexible electronics for wearable POCT systems. Furthermore, we critically discuss persistent challenges for clinical translation and commercialization, including biomarker correlation with systemic health, sample complexity, device integration, and data reliability. Finally, we offer perspectives on future directions, such as multimodal sensing, integration with intelligent algorithms, and convergence with theranostic applications.