The monocationic carrageenans were prepared as described by . Briefly, 400 mg of carrageenan were dissolved in 150 mL of 800 mM sodium chloride, 800 mM potassium chloride, or 100 mM calcium chloride. The solution was treated in a water bath at a temperature of 80 °C for 2 h. The polysaccharide was then precipitated in with two volumes of cold isopropanol (0 °C). The precipitate was washed with 80 % and 100 % isopropanol, and dried at a temperature of 50 °C.