Authors
da Silva IS, Cardoso AR, Reimer L, König A, van Riesen C, Outeiro TF, Jensen PH, Sales MGF
Journal
Biosensors and Bioelectronics
Citation
Biosensors and Bioelectronics 268 (2025) 116880.
Abstract
Aggregation of alpha-synuclein (aSyn) occurs in presynaptic neurons and constitutes a key factor for the progression of Parkinson’s disease, emphasising the urgency of early detection to support effective treatment. Unfortunately, a reliable, sensitive and cost-effective diagnostic tool has so far been lacking.
Thus, this work presents a novel biosensor for detecting aSyn using plastic antibodies coupled to electrochemical detection. This biosensor was designed for portability and compatibility with point-of-care devices and exploits the electropolymerization of methylene blue (MB) together with aSyn on the carbon working electrode of screen-printed electrodes (SPEs). By electrochemical impedance spectroscopy (EIS) measurements, the sensor showed exceptional analytical performance in detecting aSyn monomers in human CSF samples. It showed a linear trend of response from 1 fM to 10 pM with an impressively low limit of detection of 69 aM. Selectivity tests confirmed the predominant response to aSyn monomers, a less intense response to oligomers and insensitivity to fibrils.
Overall, this plastic antibody-based electrochemical sensor represents a significant breakthrough as it is the first of its kind to accurately, sensitively and selectively detect aSyn monomers with a partial response to oligomers. Its simplicity and reproducibility promise to contribute to the early and effective diagnosis of Parkinson’s disease.