Cation-selective polymeric electrodes
AssigneeMonitoring Technology Corporation
InventorsDavid M. Band, Robert A. F. Linton
Life of this patent
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Abstract
A cation-sensitive electrode which comprises an internal reference electrode, an internal reference solution and a cation-responsive membrane, characterized in that the internal reference solution contains a saturated solution of a salt of a cation other than the cation for which the cation-responsive membrane is primarily selective, the internal reference solution being formed in situ by hydration of a combination of the salt of the cation with a hygroscopic material, bu absorption of water from the atmosphere and/or by hydration of the hygroscopic material when the electrode is put into use, thereby forming the internal reference solution.
Claims20
A cation-sensitive electrode which comprises an internal reference electrode, an internal reference solution and a cation-responsive membrane, characterized in that the internal reference solution contains a saturated solution of a salt of a cation other than the cation for which the cation-responsive membrane is primarily selective, the internal reference solution is formed in situ by hydration of a combination of a hygroscopic material with the salt of the cation other than the cation for which the cation-responsive membrane is primarily selective, either by absorption of water from the atmosphere and/or by hydration of the hygroscopic material when the electrode is put into use, thereby forming the internal reference solution.
A method of measuring cardiac output in a human being which method is characterized in that it comprises:
- (i) injecting into a central vein of the human being a bolus injection of a solution of a cation which is not normally present in blood;
- (ii) measuring the dilution of the cation in the blood plasma flowing in a peripheral artery using a cation-sensitive electrode which is sensitive to the cation injected in step (i);
- and
- (iii) calculating from the dilution data obtained in step (ii) the cardiac output.
Dependencies are inferred from the claim text.