Highly sensitive photoelectrochemical sensor array for tau protein detection based on light addressing and magnetic control strategies

A label-free self-calibrating PEC sensor is designed for ultrasensitive Tau detection • γ-Fe 2 O 3 @Bi 2 S 3 nanocomposites possess excellent optoelectronic and magnetic properties. • Optical addressing and magnetic separation enable single-chip high-throughput detection. • Self-calibration design minimizes systematic errors, enhancing detection accuracy. • The sensor achieves excellent performance with a detection limit as low as 5.9 pg·mL −1 . In this study, a self-calibrating photoelectrochemical sensor was developed for the detection of Tau, a biomarker associated with neurodegenerative diseases. The sensor was constructed using γ-Fe 2 O 3 @Bi 2 S 3 nanocomposites, which exhibit a homogeneous polygonal morphology and good magnetic and optoelectronic properties. By utilizing an array configuration, this sensor ensures uniform detection environments across multiple sites and leverages magnetic separation to enhance target molecule recovery, offering a novel approach for advanced diagnostic applications in neurodegenerative disease detection. The developed sensor exhibited a linear range from 0.01 ng·mL −1 to 100 ng·mL −1 with a detection limit of 5.9 pg·mL −1 , as well as excellent selectivity, stability and reproducibility, showcasing its potential for precise and reliable biomarker detection. Download: Download high-res image (52KB) Download: Download full-size image