Fe3O4/MXene Nanosphere-Based Microfluidic Chip for the Accurate Diagnosis of Alzheimer's Disease

Amyloid fl protein oligomer (AflO) has been found to be a crucial biomarker of Alzheimer's disease (AD). Exploring an accurate detection method of AflO is of great significance for early AD diagnosis and treatment. Herein, a fluorescent biosensor for AflO detection is designed. It integrates fluorescence resonance energy transfer (FRET)-based fluorescence detection with a poly(dimethylsiloxane) (PDMS)-based microfluidic chip. The carboxyl fluorescein-modified AflO aptamers are employed as the fluorophore, and three-dimensional Fe3O4/MXene nanospheres are used as the fluorescence quencher for the first time. Moreover, the PDMS-based multichamber microfluidic chip serves as a fluorescence detection platform. The Fe3O4/MXene-based nano sphere-based biosensor shows an excellent linear relationship between the fluorescence intensity and the logarithm of the AflO concentration in the range of 0.10-200 nM. The detection limit is similar to 0.05 nM at the ultralow sample volumes of similar to 4.50 mu L. These results strongly show that the fabricated high-performance biosensor can be widely used in smart healthcare including but not limited to medical diagnosis, health monitoring, and biological studies.

Automated summary

This article describes a fluorescent biosensor for the detection of the Alzheimer's disease biomarker AflO. The biosensor combines fluorescence resonance energy transfer (FRET) detection with a PDMS microfluidic chip, and demonstrates high sensitivity and linearity. It can be widely used in medical diagnosis, health monitoring, and biological studies.