Integrated Sensing Platform Based on MOF@COF Nanocomposites for the Ultrasensitive Biosensing of Sesame Allergens Ses i 2

• Design and synthesize novel composite structural materials UIO-66-NH2@TA-COF. • UIO-66-NH2@TA-COF exhibits excellent electroactive catalytic performance. • A composite aptamer sensor sensitively spots sesame allergen Ses i 2. • This provides an enhanced and efficient method for rapid detection of Ses i 2. Sesame allergy has emerged as a public health issue due to its persistent occurrence, severe symptomatic manifestations, and widespread incidence globally. Among sesame allergens, 2S albumins (Ses i 2) is one of the widely recognized allergens, and its precise detection is urgently needed to prevent sesame-related allergies. In this work, a composite structure was designed and synthesized by combining metal ion self-assembled metal organic frameworks (MOFs) and imine constructed covalent organic frameworks (COFs) (represented by MOF@COF), which constructing a high-sensitivity sensing system for identification and detection of Ses i 2. A novel hybrid material, comprising a strategically assembled combination of UIO-66-NH 2 and TA-COF, was crafted to yield a functionalized UIO-66-NH 2 @TA-COF composite, demonstrating remarkable electrochemical performance. As a result, a significant quantity of aptamer strands can adhere to the UIO-66-NH 2 @TA-COF surface resulting from robust π-π stacking interactions. With the change in the relative concentration of Ses i 2 from 5 to 650 nM, the UIO-66-NH 2 @TA-COF sensor exhibited a low detection limit of 0.13 nM, which demonstrates its extremely high sensitivity. In addition, the UIO-66-NH 2 @TA-COF sensor exhibited excellent reproducibility, stability and specific recognition ability to Ses i 2. Therefore, this innovative sensor exhibits great potential for real-world applications in food safety.