Table 4.

Concentrations of different ions in the extracellular saline buffer and HHBS, not accounting for pH titration with NaOH or HCl.

Ion	Concentration in Extracellular Saline Buffer	Concentration in HHBS (pH 7.3, 25 °C)
Na+	140 mM	142.85 mM
K+	5.40 mM	5.77 mM
Cl−	149.40 mM	146.83 mM
Ca2+	2 mM	1.26 mM
Mg2+	10 mM	0.90 mM
SO42−	10 mM	0.41 mM
HEPES	5 mM	20 mM
H2PO4−	-	0.44 mM
HPO42−	-	0.34 mM
HCO3−	-	4.17 mM