A 3D-printed extraction device based on aptamer-functionalized metal-organic frameworks for ochratoxin A...

This work reports the development of a 3D-printed extraction device coated with an aptamer-functionalized metal-organic framework (Apt@MOF) for the selective extraction of ochratoxin A (OTA) from alcoholic beverages. Several MOFs were initially screened under dispersive solid-phase extraction (dSPE) conditions, identifying UiO-66-(COOH)₂ as the most suitable support due to its minimal non-specific OTA retention, thus maximizing the contribution of Apt-based recognition. After selecting Apt immobilization through physical adsorption onto the MOF, the resulting hybrid material exhibited high selectivity toward OTA, being successfully immobilized onto polypropylene 3D-printed devices using a poly (vinylidene fluoride)-based coating. The optimized system provided high recoveries (91-95%), good reproducibility (RSD ≤ 5.5%), and a limit of detection of 0.06 μg L^-1, with a preconcentration factor of 4. The applicability of the method was demonstrated in wine and beer samples, showing efficient matrix clean-up and reliable OTA quantification. The combination of Apt-mediated recognition, MOF-supported immobilization, and 3D-printing versatility provides a practical, low-cost (∼0.49 € per device), and disposable alternative for selective OTA extraction from alcoholic beverages.