Five-in-one colorimetric multiplexed point-of-care testing of blood biomarkers via Janus separation-sensing membrane

Blood marker analysis technology is crucial for real-time monitoring of physiological health. However, traditional routine blood tests require prior plasma separation, consuming significant blood volume and time. This study introduces an innovative sensor platform that achieves simultaneous plasma separation and multi-marker detection in real-time, such as calcium ions (Ca²⁺), magnesium ions (Mg²⁺), chloride ions (Cl⁻), creatinine (Cr), and urea nitrogen (BUN). The sensor consists of a dedicated separation unit and a detection unit. The separation unit employs a Janus membrane with asymmetric driving to enable spontaneous plasma separation and transmission. The sensing unit contains chromogenic agents specific to Ca²⁺, Mg²⁺, Cl⁻, Cr, and BUN, facilitating colorimetric reactions for visual analysis. The detection system primarily comprises a smartphone equipped with a custom application that captures RGB values and converts them into concentration data for marker detection. This novel Five-in-One Colorimetric Multiplexed Point-of-Care Testing system not only presents a new method for real-time blood testing but also pioneers new approaches and concepts in blood diagnostics.