Durability of phosphate-selective CHEMFETs

Lipophilic uranyl salophenes derivatives I and II were used as ionophores i n membranes of phosphate-selective CHEMFETs. High selectivity for H2PO4- ov er other anions was obtained for these sensors. The influence of the ionoph ore structure on the sensor durability was investigated. CHEMFETs based on derivative II exhibited better long-term stability due to the better solvat ion of this ionophore in the membrane phase. The microsensor durability can be improved decreasing the amount of the ammonium salt in the membrane to 5% mol, with only little decrease of initial selectivity. (C) 2001 Elsevier Science B.V. All rights reserved.