Epitope-Cavities Generated by Molecularly Imprinted Films Measure the Coincident Response to Anthrax Protective Antigen and Its Segments

摘要

A molecularly imprinted film was fabricated, in the presencenof epitope-peptides, onto a quartz crystal microbalancen(QCM) chip. These five peptides are known linearnor conformational epitopes of the anthrax protectivenantigen PA83. Imprinting resulted in an epitope-cavitynwith affinity for the corresponding template. With thenuse of a basic monomer, the binding-effect was furthernenhanced increasing the affinity to nanomolar levels.nThe affinities of the peptide to their correspondingnmolecularly induced polymers (MIPs) were morenclosely related to the molecular weight of the analytenthan to the number of residues. All epitope-cavitiesndifferentiated their epitope region on the protectivenantigen PA83 as well as the corresponding furin cleavagenfragments PA63 and PA20. The QCM chip differentialnresponse to the protective antigen fragmentnwas observed in the picomolar range, thus demonstratingna method to manipulate protein on the surfacenwith defined orientation.