Development of a vitamin-protein sensor based on carbon nanotube hybrid materials

Abstract

A bionanosensor consisting of a field effect transistor chip and containing a mixture of poly(ethylene glycol)-grafted single-walled carbon nanotubes (SWCNTs) and SWCNTs modified with a protein (avidin) which binds with a specific vitamin (biotin) is developed. An increase in impedance due to biotin-avidin binding is observed when biotin is injected, while the injection of other vitamins resulted in a decrease in impedance. This bionanosensor reacts quickly (∼60s); in addition, the impedance recovers almost to its initial value when the bionanosensor is washed with distilled water; thus, the vitamins do not bind directly with the SWCNTs.