Increasing Sensitivity of Label-Free Detection Using Porous-Polymer-Integrated Metallic Mesh

Abstract

Metallic mesh is optical element which creates a localized electric field within and around openings in the mesh when incident light interacts with the openings. Using such a structure, samples do not need to be labelled and changes in the transmission property of the mesh when dielectric samples are present in the localized electric field, and it can be easily used as a sensor to detect biomolecules. For detection of minute biomolecules, such as allergens, sensitivity can be improved by actively immobilizing the sample within the localized electric field. To demonstrate the relationship between object immobilization and sensitivity, a metallic mesh prototype was developed with openings filled by an porous polymer, which has high transmission property in the Terahertz region: the light range used in this experiment. This porous polymer coating was modified to contain components which can bind a specific to biomolecule, such as streptavidin and ovalbumin. The metallic mesh demonstrated larger sensitivity when the target was immobilized on the porous polymer within and around openings of the metallic mesh.