Construction of a Portable Colorimetric Biosensing Platform Based on the Co-TCPP (Fe)-MOF Nanosheet and Its Application in Glucose Detection

Recent advancements in microfluidic paper-based analytical devices (μPADs) have demonstrated their significant potential for point-of-care testing (POCT), particularly in low-resource settings. These devices are especially promising for monitoring glucose levels in patients with diabetes, offering a cost-effective and portable solution. However, one of the primary challenges hindering the widespread adoption of smartphone-coupled μPADs has been their sensitivity to varying ambient lighting conditions, which can interfere with accurate colorimetric detection. To address this issue, researchers have introduced a novel approach involving a metal-organic framework (MOF), specifically Co-TCPP (Fe) [cobalt Fe-(III) meso-tetra-(4-carboxyphenyl) porphyrin chloride], synthesized using a straightforward method. Co-TCPP (Fe) exhibits remarkable peroxidase-like activity when exposed to hydrogen peroxide (H₂O₂), enabling it to interact effectively with classic chromogenic substrates and thus improving the colorimetric reaction crucial for accurate glucose detection. In this study, the team developed paper-based μPADs that incorporate the Co-TCPP (Fe) MOF, allowing it to accurately detect glucose levels across a wide concentration range. The limit of detection (LOD) achieved was 5.3 μM, with a linear detection range from 5 to 750 μM. This innovation addresses previous concerns regarding the impact of environmental lighting fluctuations and varying shooting angles, ensuring the reliability of glucose measurements under uncontrolled conditions. By integrating this algorithm into a smartphone-coupled μPAD system, the researchers have created a portable, high-resolution platform that delivers dependable results, even in challenging and fluctuating environments. This breakthrough marks a significant step toward enhancing the practicality and accessibility of glucose monitoring in resource-constrained settings, providing a valuable tool for both clinical and everyday use.