Molecularly Imprinted Polymers Combined with Plasmonic Plastic Optical Fibers for Glyphosate Detection

The widespread use of glyphosate (GLY) in agriculture poses significant toxicological risks to human health and ecosystems. Ensuring the rapid and continuous monitoring of this herbicide and its metabolites is crucial to adhere to legal limits and safeguard public health. In this work, a surface plasmon resonance (SPR) platform, based on a D-shaped plastic optical fiber (POF), covered with an acrylic-based molecularly imprinted polymer (MIP) layer, is proposed for the detection of GLY in aqueous matrices. In particular, a thick MIP layer is deposited over the plasmonic sensitive surface as a molecular recognition element for the selective detection of GLY at micromolar concentrations range. The proposed optical-chemical sensor chip demonstrated a limit of detection (LOD) of about 160 nM and a range of detection up to about 12 μM of GLY. This work aims to expand the detection range of a previously presented ultra-sensitive POF -based GLY sensor. By the combination of these two different GLY sensors, an ultra-wide detection range can be obtained. The proposed SPR-POF-MIP sensor is useful to investigate contexts highly contaminated by this herbicide.