Novel biomimetic Prussian blue nanocubes-based biosensor for Tau-441 protein detection

Abstract

Tau protein is a promising biomarker for early diagnosis of Alzheimer's disease (AD). Therefore, there is an urgent need to develop a simple and effective method for its detection. To this end, an innovative sensing device was developed using a carbon screen-printed electrode (C-SPE) decorated with graphene oxide/Prussian Blue nanocubes (GO/PBNCs) for the selective and sensitive determination of Tau-441 protein. The biorecognition layer was built on the rGO/PBNCs/C-SPE by electropolymerizing 3-aminophenol (3-AMP) in the presence of the target protein using chronoamperometry, and the template was subsequently removed from the polymer matrix with oxalic acid. In parallel, a non-imprinted material (NIP) was also prepared in the absence of the target for comparison purposes. Scanning electron microscopy, transmission electron microscopy, and Raman spectroscopy were used to study the morphology of the modified electrode, and electrochemical techniques were used to monitor the stepwise assembly of the sensor. Under optimized conditions, the sensing platform exhibited a linear range of 1.09 pmol/L and 2.18 nmol/L and a detection limit of 0.01 pmol/L in spiked PBS solution. The molecularly imprinted polymer (MIP) sensor showed minimal interference with uric acid and bovine albumin. The simplicity of production, affordable cost and promising performance make this sensor a potential strategic sensing platform for the detection of chemical and biological molecules.