ORCID
- S. Nazir: 0000-0001-9460-3627
- G. Pan: 0000-0002-2678-7898
Abstract
A consistent and reproducible chemical modification of the transducer interface is essential to ensure effectiveimmobilization of bioreceptors, thereby improving the sensitivity and reproducibility of biosensors. Althoughnotable progress has been made in fabricating graphene-based biosensors, the effects of surface biofunctionalization on sensing performance remain not fully understood. This study shows that combining threedimensional (3D) graphene foam electrodes with a straightforward, single-step surface biofunctionalizationmethod is key to enhancing the performance of graphene-based biosensors. Specifically, it presents a single-stepapproach to functionalize the 3D graphene foam (Gii-Sens) with 1-pyrenebutyric acid N-hydroxysuccinimideester (Pyrene-NHS ester). Electrochemical techniques, including cyclic voltammetry (CV) and differential pulsevoltammetry (DPV), confirmed the successful attachment of Pyrene-NHS ester to the graphene foam surface, atlevels sufficient to serve as a covalent linker for antibody attachment. The graphene structure was maintainedthrough non-covalent functionalization, and the linker's functionality was verified using the functionalized GiiSens electrochemical sensor for detecting Tau-217 peptides. Measurements with the developed electrochemicalsensor showed a linear response to Tau-217 peptides within the 1 fM to 1 nM concentration range, with a limit ofdetection (LoD) of 0.41 fM in both phosphate-buffered saline PBS and serum. The sensor's reproducibility andrepeatability were tested using the standard addition method, resulting in a relative standard deviation (RSD) ofless than 5%. Specificity was evaluated against Tau-181, Tau-441, amyloid proteins (Aβ1-40 and Aβ1-42), andbovine serum albumin (BSA).
DOI Link
Publication Date
2026-02-11
Publication Title
Biosensors and Bioelectronics: X
Volume
29
Acceptance Date
2026-02-10
Deposit Date
2026-03-05
Funding
This work is financially supported by the European Union#8217; s HORIZON-MSCA Doctoral Networks 2021 program under grant agreement No. 101071485. This research was funded by the Engineering and Physical Sciences Research Council (EPSRC) under grant number EP/X025578/1.
Additional Links
https://www.scopus.com/inward/record.url?eid=2-s2.0-105030925160&partnerID=MN8TOARS
Keywords
Early detection, Electrochemical immunosensor, Graphene foam, Pyrene-NHS ester, Tau-217
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 International License.
Recommended Citation
Nazir, S., Jenkins, D., & Pan, G. (2026) 'Rapid electrochemical biosensor with enhanced accuracy and repeatability using Pyrene NHS ester modified 3D graphene electrodes', Biosensors and Bioelectronics: X, 29. Available at: 10.1016/j.biosx.2026.100757
