Porous Framework Materials and MXenes as Biosensing Platforms for Amyloid-β Detection

Amyloid-β (Aβ), a 39-43-amino-acid peptide, is closely associated with the pathogenesis of Alzheimer's disease (AD) and undergoes abnormal aggregation that contributes to disease progression. Therefore, rapid and accurate Aβ detection is essential for early AD diagnosis and therapeutic monitoring. Biosensors have emerged as promising analytical tools owing to their simplicity, low cost, high sensitivity, and selectivity. In particular, metal-organic frameworks, covalent organic frameworks, hydrogen-bonded organic frameworks, and MXenes offer unique structural and functional advantages for Aβ sensing. This review summarizes recent advances in Aβ biosensors based on these materials, with emphasis on comparative analytical performance across electrochemical, optical, photoelectrochemical, and dual-mode platforms. Current challenges, including matrix interference, limited discrimination of Aβ isoforms, and biosensor miniaturization, are discussed. Future directions involving artificial intelligence and machine learning are also highlighted to advance rapid, sensitive, and accurate Aβ detection for early AD diagnosis and therapeutic monitoring.