CYCLOPROPYLAMINE PLASMA POLYMER SURFACES IN QUARTZ CRYSTAL MICROBALANCE AND SURFACE PLASMON RESONANCE IMMUNOSENSING

Immunosensors with highly sensitive and rapid detection capabilities of various biomolecules are of a great demand in the field of biomedicine and environmental control. The two mostly employed transducer principles are either optical surface plasmon resonance (SPR) and mass sensitive quartz crystal microbalance (QCM). The first task encountered in the immunosensor development is the preparation of a coating matrix suitable for the immobilization of antibody on the golden layer of SPR or QCM. The most popular approaches are based on wet chemical treatments such as self-assembled monolayers (SAMs) of alkanethiols, disulfides, or polyethylenimine (PEI). However, these approaches suffer from several drawbacks such as a poor stability, long time preparation, unstable baseline or a high level of noise. As an alternative to SAMs, the deposition of thin functional coatings by plasma polymerization can be employed. The plasma polymerization has already been successfully applied to the deposition of thin films containing carboxyl, amine, anhydride groups. In this work, pulsed plasma polymerization of cyclopropylamine is employed to deposit stable amine-rich thin films on the surfaces of QCM and SPR chips. The AL-01 antibody, specific to human serum albumin (HSA), was attached to the QCM and SPR chips surfaces via glutaraldehyde activation. For the developed immunosensors the stable baseline was recorded. Selective and high response was achieved during the reaction with the solution of antigen. The results confirmed that the introduced methodology have a great potential for biosensing applications.