title: Bioluminescent flow sensor for L-phenylalanine determination in serum.
abstract: A highly sensitive and rapid bioluminescent flow sensor was developed for the determination of the content of L-phenylalanine (Phe) in serum by monitoring the reduced form of nicotinamide adenine dinucleotide (NADH), produced by immobilized phenylalanine dehydrogenase (PheDH), with bacterial bioluminescent enzymes immobilized on a separate nylon coil. The L-PheDHs extracted from Bacillus badius, Bacillus sphaericus and Rhodococcus sp. M 4 were investigated and the performances of the three immobilized L-PheDH's were analysed. The B. badius reactor was found to give higher transformation rate and better sensitivity; the response was linear from 1 to 100 microM at 25 degrees , with a detection limit of 10 pmoles (0.5 microM). The intra- and inter-assay coefficients of variation were less than 5% and recoveries ranged from 90 to 101%. The results agreed well with those obtained with a chromatographic method for the Phe determination in serum and with the normal reference values.
authors.affiliation: Institute of Chemical Sciences, University of Bologna, via S. Donato, 15-40127 Bologna, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Girotti
authors.forename: E
authors.initials: E
authors.lastname: Ferri
authors.forename: S
authors.initials: S
authors.lastname: Ghini
authors.forename: R
authors.initials: R
authors.lastname: Budini
authors.forename: G
authors.initials: G
authors.lastname: Carrea
authors.forename: R
authors.initials: R
authors.lastname: Bovara
authors.forename: S
authors.initials: S
authors.lastname: Piazzi
authors.forename: R
authors.initials: R
authors.lastname: Merighi
authors.forename: A
authors.initials: A
authors.lastname: Roda