A reflection scheme for optical-chemical sensors via light-diffusing fibers and molecularly imprinted polymers

In this work, a simple and low-cost optical-chemical sensor configuration based on Light-Diffusing Fibers (LDFs) and Molecularly Imprinted Polymers (MIPs) for the selective detection of 2-Furfuraldehyde (2-FAL) is developed and tested. The LDF and MIP are located in a C-shaped channel created into a polyvinyl chloride (PVC) hollow jacket. As a proof of concept, an MIP prepolymeric mixture for 2-FAL is poured into the channel with the LDF at the end and then polymerized via a thermal process. The optical-chemical probe is obtained via the silica LDF in a reflection sensing scheme to launch the light into the MIP and collect the backscattered one. Aqueous solutions perform binding tests at increasing 2-FAL concentration in contact with the MIP receptor via a 3D-printed measuring cell. The proposed sensor presents a limit of detection (LOD) estimated at 33 nM, similar to other sensitive optical-chemical sensor configurations.