Synergistic Interface Topological Engineering Enables Stable and Ultrasensitive Detection of Allergen-Specific Immunoglobulin E in Human Serum.

Abstract

Constructing high-performance interfaces capable of precisely transducing bioelectronic signals is central to next-generation personalized medicine and point-of-care testing. However, current strategies designed to overcome the Debye screening effect in physiological fluids still face considerable challenges, including compromised biological activity and complex fabrication procedures. Here, we propose a kinetically controlled interface topological engineering strategy that utilizes nanoconfined spaces to promote electric double-layer overlap. This approach effectively modulates the thermodynamic ion distribution and increases the sensing distance by reducing local screening via EDL overlap in nanoconfined concavities, thereby substantially improving signal transduction in high-ionic-strength environments. Facilitated by a triple synergistic mechanism integrating physical antiscreening, zero-linker chemical anchoring, and environmentally stable encapsulation, this morphology-functionalized organic field-effect transistors (OFETs) platform achieves ultrasensitive detection of allergen-specific immunoglobulin E in complex biological environments such as human serum. The achieved limit of detection is as low as 25.35 pg mL^-1 with microliter-scale sample of 2.5 μL consumption, markedly surpassing conventional clinical thresholds (840 pg mL^-1). This synergistic strategy provides a simple and versatile physical route for constructing high-performance OFETs biosensors under complex clinical conditions.