title: Development of a sensor system for the determination of sanitary quality of grapes.
abstract: n instrument for the automatic quantification of glycerol in grapes has been developed. We verify here that this analyte can be used as a benchmark of a serious disease affecting the grapevines, namely Botrytis cinerea. The core of the instrument is an amperometric biosensor consisting of a disposable screen printed electrode, generating the analytical signal thanks to a bi-enzymatic process involving glycerol dehydrogenase and diaphorase. The full automation of the analysis is realised by three micropumps and a microprocessor under control of a personal computer. The pumps allow the correct and constant dilution of the grape juice with a buffer solution also containing [Fe(CN)6]3- redox mediator and the injection of NAD+ cofactor when the baseline signal reaches a steady state; the instrument leads to automated reading of the analytical signal and the consequent data treatment. Although the analytical method is based on an amperometric technique that, owing to heavy matrix effects, usually requires an internal calibration, the analyses indicate that a unique external calibration is suitable for giving accurate responses for any grapes, both white and black ones.
authors.affiliation: Department of Chemical and Geological Sciences, University of Modena and Reggio Emilia, Modena, Italy. chiara.zanardi@unimore.it
authors.forename: Chiara
authors.initials: C
authors.lastname: Zanardi
authors.forename: Luca
authors.initials: L
authors.lastname: Ferrari
authors.forename: Barbara
authors.initials: B
authors.lastname: Zanfrognini
authors.forename: Laura
authors.initials: L
authors.lastname: Pigani
authors.forename: Fabio
authors.initials: F
authors.lastname: Terzi
authors.forename: Stefano
authors.initials: S
authors.lastname: Cattini
authors.forename: Luigi
authors.initials: L
authors.lastname: Rovati
authors.forename: Renato
authors.initials: R
authors.lastname: Seeber
mesh_terms: D001331:Automation; D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods*; D020171:Botrytis; D004563:Electrochemistry; D005990:Glycerol / Q000032:analysis; D027843:Vitis / Q000382:microbiology*
chemical_list: D005990:Glycerol