Determination of histamine release from mast cells using a histamine-sensitive membrane electrode

Prothiofos (O-(2,4-dichlorophenyl) O-ethyl S-propyl phosphorodithioate), an agricultural chemical, can be used as a membrane solvent to make a histamine-sensitive membrane electrode. An electrode constructed using prothiofos as membrane solvent and sodium tetrakis[3,5-bis(2-methoxyhexafluoro-2-propyl)phenyl]borate as an ion-exchanger in a poly(vinyl chloride) membrane matrix exhibited a near-Nernstian response to histamine in the concentration range 5 x 10(-5)-1 x 10(-2) M with a slope of 56 mV per concentration decade in a physiologically balanced salt solution containing 154 mM NaCl, 2.7 mM KCl, 0.9 mM CaCl2, 5.6 mM glucose and 10 mM 4-(2-hydroxyethyl)-2-piperazineethanesul acid (HEPES)-NaOH (pH 7.4). The limit of detection was 2 x 10(-5) M. This electrode is used to determine histamine release from mast cells. The histamine concentrations determined agreed well with those determined by an established fluorimetric assay. (C)1999 Elsevier Science B.V. All rights reserved.