Characterization of acrylate-based ChemFET sensor for nitrate sensing and monitoring

Solid-state nitrate ion sensor or nitrate-ChemFET (N-ChemFET) based on polymeric membrane materials was fabricated and developed for the determination of nitrate ion in aqueous solution. The membrane materials used consisted of methyl-methacrylate (MMA) and tetrahydrofurfuryl-acrylate (THFA) as copolymers, tetraoctylammonium nitrate (TOAN) as an ion-exchanger and other lipophilic additives. N-ChemFET characterizations included a study on sensitivity, pH effect, interference, temperature effect and lifetime demonstrated good performance of N-ChemFET in sensing nitrate as an ion of interest. N-ChemFET sensor showed a lifetime of at least 3 months at room temperature (RT) where no leaching and detachment of the membrane layer occurred. Therefore, this requirement is applicable for the purpose of sensor application in the industry for monitoring the level of nitrate in aquatic environment by periodical measurement method.