Design and fabrication of nanostructured disposable electrochemical bio-sensing chips for the quick monitoring of Alzheimer's disease biomarkers

Design and fabrication of nanostructured disposable electrochemical bio-sensing chips for the quick monitoring of Alzheimer's disease biomarkers Background Figure 2: (A-B) Nanomaterial Composite selection. (A) Cyclic voltammetric (CV) characterization of printed electrodes modified with different nanomaterial composites. (B) Electrochemical impedance spectroscopic (EIS) characterizations of printed electrodes modified with different nanomaterial composites. Conclusion and Future Direction Nehal I. Ghoneim 1, 2 , Ahmed Abdellatif 1* and Rabeay Y. A. Hassan 2* 1. Biotechnology graduate program, and Department of biology, School of Sciences and Engineering, the American University in Cairo, Cairo 11835, Egypt. 2. Biosensors Research Center, University of Science and Technology (UST), Zewail City of Science and Technology, Giza 12578, Egypt. Figure 4: Testing the immune-sensing times effect on the capturing efficiency of the antigen. Catching Alzheimer’s Before It Catches Memories: Early Signals, Lasting Memories with Biosensing. Neurodegenerative diseases (NDs) like Alzheimer’s disease (AD), Parkinson’s disease, and ALS involve progressive neuronal degeneration, with AD being the most prevalent dementia type, marked by memory loss and affecting ~50 million people globally. Its pathology features amyloid-beta plaques and tau protein tangles, causing neuronal death. Current diagnosis relies on invasive, costly methods like brain imaging and CSF analysis, hindering early detection. Electrochemical nano-biosensors offer a transformative solution, enabling rapid, noninvasive, and sensitive detection of biomarkers such as amyloid-beta oligomers and phosphorylated tau proteins. These biosensors leverage nanocomposites and molecularly imprinted polymers to enhance specificity and portability for point-of-care use. Our study focuses on developing an immunosensor platform using screen-printed electrodes to detect plasma AD biomarkers, aiming to improve early diagnosis and patient outcomes globally. Steps of fabrication of the immune-sensing system - 1. Abbasi, H. Y., Tehrani, Z., Devadoss, A., Ali, M. M., Moradi-Bachiller, S., Albani, D., & Guy, O. J. (2021). Graphene based electrochemical immunosensor for the ultra-sensitive label free detection of Alzheimer's beta amyloid peptides Aβ (1–42). Nanoscale Advances,3(8), 2295-2304. 2. Sharma, A., Angnes, L., Sattarahmady, N., Negahdary, M., & Heli, H. (2023). Electrochemical Immunosensors Developed for AmyloidBeta and Tau Proteins, Leading Biomarkers of Alzheimer’s Disease. Biosensors,13(7), 742. References This work is supported by the AUC research support grant, and the joint EPFL-UM6P initiative “Excellence in Africa”, the 100 PhDs for Africa programme. Acknowledgment Methodology AB Figure 3: (A) EIS Characterization of printed electrodes with different crosslinkers ( electrodeposited POPD vs 4-ATP, (B) EIS monitoring of the immunosensor manufacturing steps including the drop-casting of nanocomposites onto the printed electrode surface, formation of a self-assembled monolayer of the P-OPD, conjugation of the antibody, blocking the non-specific binding with the BSA. Figure 5: Nyquist plots generated by the Amyloid beta-42-immunosensor against different concentrations of Amyloid beta-42. Calibration curve of the Amyloid beta-42. ΔRct values are extracted from (A) through a modeled equivalent circuit. Figure 6: Selectivity testing of the Amyloid beta-42 -immunosensor towards non-targeting common biomarkers. Ten-fold increase in the concentration of each of the non-targeting molecules was used for this experiment. The MWCNT-Ru nanocomposite significantly enhanced the immunosensor’s sensitivity, enabling rapid, low-concentration detection of amyloid-beta-42 (LOD: 0.002 ng/mL) with high selectivity against non-target biomarkers. This cost-effective, portable platform shows promise for earlyAlzheimer’s diagnosis in point-of-care settings. Figure 1: Graphical Abstract of the work. SEM images of (A) Electrodeposited P-OPD on the surface of the modified electrode with MWCNT-Ru composite. (B) Ruthenium (Ru) nanoparticles. Contact : Nehalgho[email protected]