Guest Talk: Giorgio Carta

Monday, 22nd of May 2023, 2 pm

Muthgasse 11, MUG 3, ground floor, SR3

Chromatography is the workhorse of the process-scale purification of proteins and other biotherapeutics. Although, ideally, retention of the native structure is desired during processing, in practice, conformational change, unfolding, and on-column aggregate formation are observed for a variety of proteins on chromatographic media including ion exchangers and hydrophobic interaction matrices. In these cases, multiple peaks are observed to elute from chromatographic columns even though only a pure protein is loaded. The most common interpretation of on-column aggregate formation is that proteins are destabilized by partial unfolding while bound to the chromatographic surface. When the destabilized molecules are desorbed in a mobile phase with increasing eluting strength, they form aggregates in solution that are detected at the column outlet. In other cases, proteins have been shown to aggregate directly on the surface. In this case, monomer, dimer, and higher-order aggregates can be eluted sequentially at increasing eluting strength. In either case, recovery and separation efficiency are impacted. Additionally, these phenomena complicate the development of mechanistic models since the classical, thermodynamics-based approaches for the description of protein-surface interactions do not take such phenomena into account. In this presentation, I will share our recent efforts to understand and model these effects using a variety of macroscopic and microscopic approaches for different antibodies, bispecific antibodies, and various aggregation-prone proteins.

Giorgio Carta is the Lawrence R. Quarles Professor at the University of Virginia. He received his Laurea in Chemical Engineering from the University of Cagliari, Italy, in 1980 and his PhD in Chemical Engineering from the University of Delaware in 1984. He has authored/co-authored 175 refereed journal articles, co-authored the first and second editions of the book “Protein Chromatography – Process Development and Scale-Up,” Wiley- VCH, 2010 and 2020, co-edited Section 16 “Adsorption and Ion Exchange” of Perry's Chemical Engineers' Handbook, McGraw-Hill, 7th, 8th, and 9th editions and authored the book “Heat and Mass Transfer for Chemical Engineers – Principles and Applications,” McGraw-Hill, 2021. He has served as the PREP Symposium Chair annually from 2009 through 2022. In addition to his university teaching, he has also been involved extensively in professional education and has been a consultant for a number of chemical and pharmaceutical companies. He is a Fellow of the American Institute of Chemical Engineers (AIChE) and of the International Adsorption Society (IAS).

You are cordially invited to join this talk.