Inventors:
Xihai Mu - Chino Hills CA
Chandra P. Jain - Placentia CA
Assignee:
Beckman Coulter, Inc. - Fullerton CA
International Classification:
G01N 27333
US Classification:
204418, 21050028, 21050027
Abstract:
A lithium ion-selective membrane that favors the bonding of lithium and depresses sodium interference is invented by a charge balance approach. A lithium ion-selective electrode (Li-ISE) having the membrane of this invention demonstrates a fast kinetic response, good precision and reproducibility, high sensitivity and the ability to retain the sensitivity after a long-term contact with biological samples. The sensor shows Nernst linearity with a slope of 55. 4 mV for lithium ion concentrations between 0. 5 mol/L and 10 mmol/L. The membrane includes at least about 2% by weight of 6,6-dibenzyl-1,4,8,11 tetraoxacyclotetradecane ionophore; from about 0. 025% to about 1% by weight of potassium tetrakis(4-chlorophenyl)borate additive; a plasticizer; and a polymeric material.