Apatite-based media have been shown to be effective chromatographic supports for monoclonal antibody (mAb) purification. CHT ceramic hydroxyapatite and CFT ceramic fluoroapatite media are multimodal chromatographic supports that interact with biomolecules through cation exchange via phosphate groups, through metal affinity via calcium atoms, or both. The two chromatographic media are different from typical polymer-based resins in that they are both the support matrix and the ligand. The protein accessible groups in CHT ceramic hydroxyapatite are Ca2+, PO43-, and OH; they are Ca2+, PO43-, and F in CFT ceramic fluoroapatite. Substitution is performed by chemical conversion of hydroxyapatite nanocrystals to fluoroapatite with a fluorine reagent.
This tech note describes the purification of a chimeric IgG mAb using a two-step purification platform consisting of UNOsphere SUPrA™ medium capture followed by a CHT ceramic hydroxyapatite or CFT ceramic fluoroapatite media polishing step. The results demonstrate that both CHT and CFT deliver highly purified chimeric IgG by removing leached protein A, host cell protein (HCP), DNA, and mAb aggregates.