pH Elution Properties of Purolite™ Affinity Resins

Overview

Protein A affinity resins play a crucial role in purifying monoclonal antibodies (mAbs) and related therapeutic molecules, serving as the most reliable and efficient initial step in downstream purification.

During the purification step, after the target molecule binds to the affinity column, the pH is lowered to achieve elution. However, some mAbs are damaged at low pH levels, while other antibodies, including bispecifics, show high aggregation. For such molecules, a mild pH elution is particularly beneficial.

This study compares the pH elution of two market-leading resins with two Purolite protein A resins, one specifically designed for high pH elution.

Conclusion

The study showed that three of the resins (Purolite Praesto Jetted A50, Competitor A, Competitor B) eluted around pH 4 or below. However, Purolite Praesto Jetted HipH demonstrated a considerably higher pH elution.

The high pH elution of Purolite Praesto Jetted A50 HipH is a key feature of the resin, designed into the ligand to allow for maximum recovery of the target molecule when aggregation proves challenging, particularly with bispecific antibodies and other complex structures with multiple functionalities.