Clinical Significance

Bicarbonate is the second largest fraction of the anions in plasma. Included in this fraction are the bicarbonate (HCO3-) and carbonate (CO32-) ions, as well as the carbamino compounds. At the physiological pH of blood, the concentration of carbonate is 1/1000 that of bicarbonate. The carbamino compounds are also present in such low quantities that they are generally. not mentioned specifically.  

Several different methods for the determination of bicarbonate in serum and plasma have been reported. Most of these procedures utilize acidification of the sample and conversion of all carbon dioxide forms to CO2 gas. The amount of gas formed is measured by manometric or volumetric devices, ion selective electrodes, or spectrophotometric techniques. These methods are either cumbersome, time‑consuming, technique‑oriented, and/or require special equipment.

_{Source: Roche Cobas CO2-L Method Sheet Version 3.0 2023-02}