Determination of beta-lactoglobulin in foods via colorimetric paper-based aptasensor using bimetallic MOFzyme

This study developed a paper-based colorimetric aptasensor for the detection of β-lactoglobulin (β-LG) in foods, using copper‑cobalt metal-organic framework (CuCo-MOF) as the core catalyst. The sensor achieved a detection limit as low as 0.102 mg/L. and a wide linear range (0.39–1250 mg/L). It offered a simple detection procedure with less than 20 min detection time, making it more suitable for on-site food safety screening. Validation with commercial ELISA confirmed its suitability for analyzing real-food samples, such as milk and infant formula. The developed paper-based RGB colorimetric aptasensor emerges as a user-friendly and economical assay for high-throughput, visual, and accurate determination of β-LG in foods.