Application of Debye-Huckel theory in calculating ionic strength of deionized water based on ionic composition detected by ICP-MS

Ionic strength of water influences the aggregation and dispersion of nanoparticles and other colloidal substances. Hence, it is of value to calculate the value for any type of aqueous solvent, and one good approach for estimating it for dilute solutions is Debye-Huckel theory. Using the theory, this Excel spreadsheet demonstrates the calculation of ionic strength of deionized water with ionic composition of the water detected by inductively coupled plasma mass spectrometry (ICP-MS). The final calculated ionic strength of deionized water was 0.001 M, with major contributions coming from the dominant cations of sodium, potassium, magnesium, and calcium. Overall, the demonstrated approach could be applied to other dilute aqueous solvent, with solvent’s ionic composition derived from ICP-MS analysis.