Potassium sulfate is used in various industrial and research applications. Industrial uses include fertilizer production, the manufacture of potassium alum, potassium carbonate, and glass. Analytical applications include the Kjeldahl method for the determination of nitrogen and protein in foodstuffs. It has been used to research electrostatic effects on pKa values of amino acid residues in the staphylococcal nuclease. When a buffer with a high zwitterionic salt concentration is used, Potassium sulfate can be used to improve protein separation via capillary zone electrophoresis. It has been reported to be useful to adsorb immune complexes on agarose derivative adsorbents.