Development of a highly sensitive chemiluminescence flow-injection analysis sensor for phosphate-ion detection using maltose phosphorylase

A chemiluminescence flow-injection analysis biosensor has been constructed for phosphate-ion detection. This system is coenzymeless and employs a maltose phosphorylase, mutarotase, and glucose-oxidase (MP-MUT-GOD) reaction system combined with an Arthromyces ramosus peroxidase-luminol reaction system. The system consists of a column packed with MP-MUT-GOD immobilized on N-hydroxysuccinimide beads, a mixing joint for the chemiluminescence reaction, and a photomultiplier. The response provided by this system was linear, with a wide range between 10 nM and 30 mu M phosphate ion, and a measuring time of 3 min per sample. Under the optimal condition, the sensor was able to detect 1.0 mu M phosphate ion for at least 2 weeks. For a practical application, the determination of phosphate ion in river water was examined using ethylenediaminetetraacetic acid, and the results were estimated by comparing with the molybdenum-blue method. (C) 1999 Elsevier Science B.V. All rights reserved.