Characterization and classification of Spanish paprika (Capsicum annuum L.) by liquid chromatography coupled to electrochemical detection with screen-printed carbon-based nanomaterials electrodes

Abstract

Screen-printed electrodes based on graphite, carbon nanotubes, carbon nanofibers, and graphene were tested as amperometric detectors for the determination of polyphenols by high performance liquid chromatography (HPLC). The chromatographic performance as well as the obtained sensitivity, detection and quantification limits suggest that carbon nanofibers modified screen-printed electrode (SPCE-CNF) is the amperometric sensor that provides the best analytical performance. Upon this confirmation, chromatographic data obtained using SPCE-CNF were exploited by means of linear discriminant analysis to successfully characterize and classify 96 Spanish paprika (Capsicum annuum L.) samples with protected designation of origin: from La Vera (including sweet, bittersweet and spicy types) and from Murcia (including sweet and spicy types).