Investigating the Kinetics of Antibody Adsorption onto Polyethylene Terephthalate (PET) Modified with Gold Nanoparticles in Flow Microchannel
Résumé
The real-time monitoring of the adsorption kinetic of antibody onto polyethylene terephthalate (PET) modified with
gold nanoparticles (NPs) is performed into a dielectric flow microchannel. The principle is based on the microelectrode–
dielectric interface excitation by a modulated voltage excitation through the dielectric layer with high
frequency range. The set-up configuration using a homemade current-to-voltage converter has been developed for fast
monitoring of biomolecule adsorption without direct electrical contact of microelectrodes with the microchannel flow.
The change in the interfacial admittance, related to the output voltage measured through the microchip, during
antibody incubation, gives information on the kinetics involved while antibodies are adsorbed at the interface. An
example of adsorption on PET modified with gold NPS was taken. Experimental data were fit with the Langmuir
equation and a good correlation was obtained with this latter, where the equilibrium constant, K, was found as 1.55 ×
108 M−1 with a limit of detection for antibody concentration without depletion equal to 8.25 nM.