Molecularly imprinted polymer for label-free integrated optical waveguide bio(mimetic)sensors

A molecularly imprinted polymer (MIP) has been developed and characterized as a photonic material for integrated optics based antibiotic sensing. Key parameters – refractive index, optical attenuation and porosity – of the synthesized polymer have been determined by employing two light transmission methods: visible/near-infrared spectrophotometry and efficiency measurement of transmissive polymer diffraction gratings. In both cases, the porous polymer samples were infiltrated with colorless liquids with different refractive indexes, modulating the material optical behavior. The MIP optical response to target molecule (antibiotic enrofloxacin) has been also studied via optical diffraction. Based on the measured optical parameters and molecule recognition response, a Si3N4/SiO2 strip waveguide sensor with a MIP sensing layer has been proposed and designed by numerical waveguide modeling.