Parafilm-laminated microfluidic cloth devices: A durable graphdiyne-based nanozyme platform for machine learning-assisted antibiotic detection.

Point-of-care testing (POCT) for antibiotic residues is in high demand for food safety supervision. However, the development of low-cost, durable, and easily fabricated analytical devices remains a challenge. Here, we reported a facile hot-pressing strategy to fabricate Parafilm-laminated microfluidic cloth-based analytical devices (P-μCADs) using a hydrophilic chemical fiber cloth substrate and commercial Parafilm as a hydrophobic barrier. Optimized at 105 °C and 6.8 MPa for 3 min, the molten Parafilm fully infiltrated the cloth fibers and formed well-defined and durable barriers with exceptional resistance to organic solvents and surfactants. The fabricated P-μCADs achieved a minimum functional hydrophilic channel width of approximately 420 μm and an ultra-low manufacturing cost (<0.05 RMB per device), demonstrating the potential for large-scale production. To distinguish the types and concentrations of antibiotics, a colorimetric detection array was constructed on the P-μCADs by integrating a peroxidase-mimicking graphdiyne-based nanozyme, coupled with linear discriminant analysis for data classification. Moreover, a support vector machine model was developed to analyze real milk samples. The model achieved high diagnostic performance, with accuracy, sensitivity, and specificity all reaching 95.0%. Featuring ultra-low cost, operational simplicity, and high chemical stability, the proposed P-μCADs platform holds great potential for POCT in resource-limited settings and offers a versatile strategy for rapid analytical screening.