My project is about electrochemical biosensor for a breast cancer …

I have a problem…

In my project a glassy carbon electrode (GCE) modified with electrodeposited Au nanoparticles (AuNps), an aptamer (Apt) against breast cancer marker was then immobilized on the Aunps.

After that marker was immobilized on the aptamer but I don’t have a correct results because aptamer is removed from the electrode.

I used of BSA blocking after aptamer but my problem don’t solve it.

I have checked attachment aptamer with marker by agarose gel electrophoresis (2%), and it was matched.

Please guide me

Thanks alot