Sandwich type biosensor of ε-subunit of FoF1-ATPase for ultrasensitive-detection of Bladder cancer cell

Abstract

It was an important challenge for bladder cancer diagnosis that to design a sandwich-type biosensor was used for ultrasensitive-detection of Bladder cancer cell. This inspire was from that ε-subunit of FoF1-ATPase could be regarded as a switch of the FoF1-ATPase biosensor and its application on the ultrasensitive-detection. There was only one ε subunit in one FoF1-ATPase and this character could be used to design a real single antibody sandwich-type biosensor. Due to ε-subunit of FoF1-ATPase as an intra-molecular rotation switch in the transition inter-changeable motion, it was found that ε-subunits can be interchanged between “rotor” and “stator” and remained its different activation at each status. Furthermore, Tip-chip device fabrication, a method that combined both double antibody sandwich immunoassay and intra-rotation switch of ε subunit FoF1-ATPase, role “rotor” and ‘stator’ a signal amplification at space scale, and time scale accumulation, was a powerful method. There were two stats of the rotation switch model, one was the switch close state when the γ and ε subunits of FoF1-ATPase bound as one complex, and the other was the switch open state when the γε complex divided, the intra-molecular rotation coupling model based on the “binding change mechanism”.