Abstract:
Description of a method for the potentiometric determination of the total calcium (II) content in biological fluids (serum, plasma and urine) based on dilution of the sample. The results obtained, when compared to the usual methods in current use, show the validity of the proposed method; furthermore, the pH of the buffer solution used for diluting the sample guarantees optimum operating conditions as well as long working life of the potentiometric sensing elements and maximum reliability when compared to other methods employing acidification of the sample.
Abstract:
A system is disclosed for measuring the partial pressure of a gas, and in particular of carbon dioxide (p CO ). The system uses an electrolytic solution of weak ionic strenght which is circulated between an ion-selective electrode and a membrane permeable to gases but not to the ions and substantially distant from the electrode. The partial pressure of the gas is measured after a fraction of the electrolytic solution has been permeated by the gas present in the sample and subsequently has been transferred on the sensible portion of the electrode.
Abstract:
Description of a method for the potentiometric determination of the total calcium (II) content in biological fluids (serum, plasma and urine) based on dilution of the sample. The results obtained, when compared to the usual methods in current use, show the validity of the proposed method; furthermore, the pH of the buffer solution used for diluting the sample guarantees optimum operating conditions as well as long working life of the potentiometric sensing elements and maximum reliability when compared to other methods employing acidification of the sample.
Abstract:
A method for determining the concentrations of total calcium and at least one monovalent ion in a sample includes the steps of mixing the sample with a diluent that has a pH within the range pH 6.5 to 7.0 and includes 2-amino-2-hydroxymethyl-1,3 propanediol phosphate and is free of the monovalent ion. An aliquot of the diluted sample is concurrently contacted with a calcium-specific ion selective electrode and an ion selective electrode specifically responsive to the monovalent ion, the response of the calcium-specific ion selective electrode is measured as an indication of the concentration of total calcium in the sample, and the response of the monovalent ion specific ion selective electrode is measured as an indication of the concentration of the monovalent ion in the sample.
Abstract:
A system is disclosed for measuring the partial pressure of a gas, and in particular of carbon dioxide (p CO ). The system uses an electrolytic solution of weak ionic strenght which is circulated between an ion-selective electrode and a membrane permeable to gases but not to the ions and substantially distant from the electrode. The partial pressure of the gas is measured after a fraction of the electrolytic solution has been permeated by the gas present in the sample and subsequently has been transferred on the sensible portion of the electrode.
Abstract:
A method for determining the concentrations of total calcium and at least one monovalent ion in a sample includes the steps of mixing the sample with a diluent that has a pH within the range pH 6.5 to 7.0 and includes 2-amino-2-hydroxymethyl-1,3 propanediol phosphate and is free of the monovalent ion. An aliquot of the diluted sample is concurrently contacted with a calcium-specific ion selective electrode and an ion selective electrode specifically responsive to the monovalent ion, the response of the calcium-specific ion selective electrode is measured as an indication of the concentration of total calcium in the sample, and the response of the monovalent ion specific ion selective electrode is measured as an indication of the concentration of the monovalent ion in the sample.