Nucleotides are important biological molecules which serve as subunits of nucleic acids. They are composed of a five-carbon sugar, a nitrogenous base, and at least one phosphate group. Nucleotides cannot be retained by reverse-phase chromatography without an ion-pairing reagent due to their highly polar nature. Primesep SB is capable of retaining and separating nine nucleotides. Primesep SB is a reverse-phase column with strong embedded basic ion-pairing groups.