The present disclosure relates generally to crosslinked cation-binding polymers comprising monomers containing carboxylic acid groups and pKa decreasing groups, wherein the polymer contains i) calcium cations that are counterions to about 5% to about 75% of the carboxylic acid groups in the polymer； or ii) calcium cations and magnesium cations that are counterions to about 5% to about 75% of the carboxylic acid groups in the polymer, wherein the magnesium cations are counterions to no more than about 35% of the carboxylate groups in the polymer. The present disclosure also relates to methods of preparation of the poly mers, and compositions, formulations, and dosage forms containing the polymers, and methods of using the polymers, compositions, formulations, and/or dosage forms to treat various diseases or disorders.
