Please join the Department of Chemical Engineering for a seminar, titled Centrifugal Separation of Biotechnology, by Professor and Chair of Innovative Products and Technologies at Hong Kong Polytechnic University, Dr. Wallace Leung.
Abstract
Traditional pharmaceuticals have been made from chemical processes. Today, a significant fraction of valuable pharmaceuticals, such as hormones, insulin, growth factors, interferon, enzymes, drug intermediates, etc. are replaced by biotechnology processes. One of the building blocks is to make protein out of recombinant processes where extracellular or intracellular protein can be “engineered” and secreted from host biological cells that have been inserted with vectors carrying human genes. The host cells, e.g. the mammalian cells, bacteria and yeast can secret high amounts of recombinant protein in a bioreactor or fermenter. For extracellular protein, the first step in harvesting protein is to separate the protein from the cells.
On the other hand for intracellular protein, the bacteria cells have to be lysed first before releasing the protein in form of inclusion body, for which separation will follow. Disk stack and tubular centrifuges operating between 4,000-15,000 times gravity are popular choices to make separation of cells, cell debris, and proteins from the broth.
Dr. Leung will discuss the various scenarios of centrifugal separation of protein in clarification, separation, classification and washing during protein harvest. This is an extremely important step that affects yield and downstream processes, e.g., purification by chromatography. He will discuss testing, modelling and prediction of protein separation in protein harvesting. Further, he will talk about new technologies on separation of flocculated bio-solids and other popular biotech separation processes by centrifugation.
Biography
Professor Wallace Leung received his BS in Mechanical and Aerospace Engineering from Cornell University, and MS and ScD in Mechanical Engineering both from MIT. Since 2005, he has been Chair Professor of Innovative Products and Technologies in Mechanical Engineering at The Hong Kong Polytechnic University. Previously, Professor Leung has worked in the United States for 25 years for Gulf R&D, Schlumberger and Baker Hughes-Bird, respectively.
Since 1977, Prof. Leung has been involved with all aspects of separation. He has written a book on industrial centrifugation technology published by McGraw Hill in 1998 and Centrifugal Separation in Biotechnology published by AP/Elsevier in 2007. Both books have been used extensively as the standard reference on the subject. He has 51 US patents, of which 36 US patents are on centrifugal separations. His recent interest is in bioseparation using centrifugation.
He has delivered plenaries, keynotes and invited talks globally on the subject. Professor Leung is transdisciplinary, with expertise in mechanical, chemical, material science, environmental, biomedical and aerospace engineering. He a fellow of ASME, AICHE, AFS, HKIE and Hong Kong Academy of Engineering Sciences. He is Chairman of International Delegation on Filtration and Chairman of the 13th World Filtration Congress, San Diego, CA, April 20-24, 2020.