title: Screen-printed enzyme sensors for l-lysine determination.
abstract: Sensors for the determination of L-lysine in samples of fermentation broth have been developed. Low-cost screen-printed sensors comprising a platinum working electrode, an Ag/AgCl pseudo reference and a carbon counter electrode were used as transducers for the enzyme sensors. L-lysine-(alpha)-oxidase from Trichoderma viride has been immobilized by entrapment into a polyurethane hydrogel. Sensors were characterized for L-lysine with respect to pH value, linear range, reproducibility, repeatability, storage and working stability. The sensitivities to other amino acids were also determined. A batch system with two working electrodes, one with immobilized enzyme and one without was adapted for the determination of L-lysine by differential measurements. Good agreement was found between L-lysine concentrations measured by the enzyme sensors and by a conventional amino acid analyzer.
authors.affiliation: Institut für Chemo- und Biosensorik (ICB), Mendelstr. 7, D-48149, Münster, Germany
authors.initials: H
authors.lastname: Olschewski
authors.initials: A
authors.lastname: Erlenkötter
authors.initials: C
authors.lastname: Zaborosch
authors.initials: G
authors.lastname: Chemnitius