Control of Antibody Orientation on Graphene Using Porphyrin Linker Molecules for High-Performance Graphene-Based Immuno-Biosensors
时间:2025.12.25 发布来源:本站原创
Yin, T., Xu, X., Huang, Z., Rosa, B. G., Gaboriau, D. C. A., Merali, N., Keshavarz, M., Bin Muhammad Mustafa, A. N., Song, J., Alodan, S., Petrov, P. K., Frampton, A. E., Skinner, S. J., Alford, N., Hu, Y., Ramadan, S., and Klein, N. (2025). Control of antibody orientation on graphene using porphyrin linker molecules for high-performance graphene-based immuno-biosensors. J. Am. Chem. Soc. 147, 47638-47653.
Abstract
The appropriate orientation of antibodies on the graphene surface is
critical for the high performance of graphene biosensors. In this
article, we show that a predominantly vertical orientation of antibodies
to the graphene surface can be achieved by functionalizing the surface
with tetrakis (4-carboxyphenyl) porphyrin (TCPP). Unlike conventional
pyrene-based linkers, such as 1-pyrene butanoic acid succinimidyl ester
(PBASE), which rely on a single flexible chain, the rigid porphyrin
macrocycle of TCPP forms an extended π–π network with graphene and
provides sites for uniform and directional antibody coupling. Applying
this system to a graphene field effect transistor platform for exosome
detection, we achieved 2 orders of magnitude improvement in the
detection limit compared to PBASE-functionalized sensors. Computational
and experimental analysis revealed that the antibody can highly exhibit
vertical orientation on TCPP-functionalized graphene, while mixed
orientations on PBASE-functionalized graphene confirm that the
sensitivity enhancement is directly caused by the optimized orientation.
The high efficiency of the TCPP method was further validated by
successfully detecting pancreatic cancer exosome biomarkers in clinical
samples. This biofunctionalization method could enable ultrasensitive
detection of disease biomarkers on a graphene surface.
文章链接:https://pubs.acs.org/doi/10.1021/jacs.5c17186