DILUENT AND METHOD FOR DETERMINATION OF TOTAL CALCIUM

摘要

Diluents and methodologies for determining the concentration of total calciu m in a clinical sample (e.g. whole blood, sera plasma urine cerebro spinal fluid) containing protein~bound calcium are disclosed. Methodologies include the steps of: (a) ad- mixing the sample with a diluent, the diluent including effective amounts of a pH buffer and at least two agents capable of com- plexing free calcium in the sample, where the agent-calcium complex association constants ("log K" in base 10) each have a range from about 1.5 to about 7.0; and (b) contacting an aliquot of the diluted sample with a calcium-specific ion selective elec- trode. The response of the calcium-specific ion selective electrode is an indication of the concentration of total calcium in the sample.