Preparation of microfibrillated cellulose/polyvinyl alcohol test strip integrated with novel chemosensor for colorimetric determination of diisopropyl fluorophosphate

Abstract Exposure to the odorless or colorless nerve agents can result in organ paralysis, failure, or even death. Novel nanocomposite‐based microporous strips that can be used with the naked eye to detect diisopropyl fluorophosphate (DFP) nerve agent mimic within a few seconds have been developed. A simple preparation procedure was used to prepare novel quinoline‐bearing hydrazone‐type tricyanofuran (QHTCF) chromophore via an azo‐coupling of 8‐aminoquinoline diazonium salt with the active methyl‐containing tricyanofuran. The chemical structure of QHTCF was inspected with FTIR, ¹H/¹³CNMR, and elemental analysis. An environmentally friendly procedure was employed to prepare microfibrillated cellulose from sugarcane bagasse agricultural waste that has been one of the most well‐known solid pollutants worldwide. Therefore, it has been highly significant to find out a simple procedure to exchange sugarcane bagasse into valuable materials. Microfibrillated cellulose/polyvinyl alcohol/hydrazone (PVA‐MFC‐H) composites were prepared using different concentrations of QHTCF chromophore. With an increase in DFP concentration, the absorption intensity of the QHTCF‐containing nanocomposite rose from 426 to 562 nm. A wide range of detection limit was monitored for DFP using the current PVA‐MFC‐H sensor strip. The CIE Lab measurements demonstrated a yellow‐to‐purple color shift of PVA‐MFC‐H upon exposure to DFP. The current PVA‐MFC‐H strip demonstrated a detection limit for DFP in the range of 25–300 ppm. The current sensors were tested for their morphologies, fiber crystallinity, thermal stability, and mechanical characteristics.