Combining ionic diode, resistive pulse and membrane for detection and separation of anti-CD44 antibody

Abstract

The need for antibody proteins is growing for both diagnosis and therapy. In this work, we combine two strategies based on single nanopore sensing and multipore membrane to separate, detect and identify antibodies. This proof of concept was done for the anti-CD44. In a first step, a single nanopore with a bullet shape were designed using track-etching of polymer film and functionalized, with a PEG spacer and CD44 antigen. The detection of anti-CD44 was evidenced by an inversion of the current rectification. After demonstrating the ability to specifically detect the antiCD44 in a single nanopore, a multipore membrane with cylindrical nanopore was designed following the same protocol and used to elute a solution of anti-CD44.In a second step, the elution product was analysed using a single SiN nanopore showing that the anti-CD44 and CD44 antigen are extracted from the membrane. The analysis of the amplitude of the current blockade shows that the complex is dissociated. • Multipore and single pore track-etched membrane was designed to detect and trap antiCD44. • The membranes are functionalized with CD44 antigen to ensure the selectivity to antiCD44. • SiN single nanopore membrane was use to confirms of the presence of antiCD44 and CD44 antigen in eluted solution. • The SiN single nanopore membrane reveals that the antiCD44 and CD44 antigen complex is dissociated after elution.