Beggiato M., Payen H., Krishnamoorthy S.
Sensors and Actuators Reports, vol. 10, art. no. 100388, 2025
Engineering topography and chemistry at the molecular length scale holds significant potential to control analyte binding at the biosensing interface. Here, we investigate the influence of nanotopography on analyte capture, by receptors tethered to the sensor surface via rigid or flexible tethers. Two different scenarios for analyte binding are investigated, viz. gold nanoparticles (as pseudo analyte) to aminated surfaces and neutravidin to biotinylated surfaces. The findings reveal the impact of nanotopography to be different depending on whether the amine or biotin receptors were bound to surface via rigid or flexible tethers. In case of rigid tethers, the nanotopography was found to have an influence beyond what could be attributed to the increase in surface areas. When flexible tethers were used, the increase in analyte capture could be attributed to the increase in surface areas as well as an increase in analyte capture efficiencies due to flexible tethers. The findings highlight the nanotopography and tether flexibility as having unique potential to maximize analyte capture efficiencies on affinity biosensors. The use of nano-QCM sensors exhibiting well-defined, periodic nanotopographies proved indispensable to real-time, label-free quantification of analyte⬄nanostructure interactions at the nano biosensing interface.
