Chemiluminometric Flow Injection Analysis procedures for the enzymatic determination of L-alanine, α-ketoglutarate and L-glutamate

Chemiluminometric Flow Injection Analysis (FIA) procedures were developed for the enzymatic determination of L-alanine, alpha-ketoglutarate and L-glutamate in the cultivation medium of mammalian cells. A packed bed flow microreactor containing alanine aminotransferase and glutamate oxidase immobilized on sieved porous glass beads was combined with a chemiluminescence detector for the generated hydrogen peroxide. To catalyse the indicator reaction between luminol and hydrogen peroxide both Co(II) ions and immobilized peroxidase from Arthromyces ramosus were used in a fibre optic detector cell. L-alanine, alpha-ketoglutarate and L-glutamate can be detected over two decades of concentration magnitudes with detection limits of 2, 5 and 1 mu M, respectively. The FIA procedure was applied to determine L-alanine and a-ketoglutarate in cell cultivation media. (C) 1999 Elsevier Science S.A. All rights reserved.