A Metamaterial Buckling‐Assisted Surface‐Acoustic‐Wave Enabled Sensor (mBASES) for Versatile and Ultrasensitive Biomarker Detection

Abstract

ABSTRACT Hydrogel metamaterials with programmable microarchitectures offer a promising route for converting molecular recognition into mechanical responses. However, efficiently transducing weak biomolecular perturbations into detectable signals without relying on molecular amplification remains a fundamental challenge. Here, we report a metamaterial Buckling‐Assisted Surface‐acoustic‐wave Enabled Sensor (mBASES), which introduces a structure‐triggered physical amplification mechanism by integrating bio‐crosslinked hydrogel metamaterials with a surface acoustic wave (SAW) device. Through competitive biomolecular recognition, target binding induces hydrogel swelling that is engineered to match the critical buckling threshold of the metamaterial. This instability‐enabled pattern transformation acts as an intrinsic mechanical gain element, converting weak molecular perturbations into amplified acoustic responses through coupled modulation of phononic transmission and hydrogel–SAW interactions. As a result, mBASES establishes a transduction pathway that links molecular recognition, hydrogel deformation, structural amplification, and ultimately acoustic readout. The platform enables rapid, label‐free detection across multiple biomolecular classes, including proteins, nucleic acids, and metabolites. Clinical validation further demonstrates femtomolar‐level detection of Herpes Simplex Virus (HSV) IgG and unamplified DNA in human serum within 5–15 min using a one‐step assay. By amplifying the transduction process rather than the target molecules, mBASES establishes a versatile biosensing strategy, providing a promising platform for point‐of‐care diagnostics.