Expanded Bed Chromatography, Surface Energetics of Biomass Deposition

Abstract

The introduction of Expanded Bed Adsorption (EBA) system has made biochemical engineers face the challenge of operating a “chromatography” in the presence of biomass and other particulate components which are normally present in a crude, unclarified, feedstock. This situation can lead to detrimental consequences in terms of increased adsorbent fouling, decreased adsorbent binding capacity, and poor bed hydrodynamics. Biomass and other suspended biological material can be very sticky, depending on the type of adsorbent employed and the solution chemistry involved and thus, can create severe limitations during processing. A better local understanding of biomass deposition, including the two separate cell‐to‐bead (“interaction”) and cell‐to‐cell (“aggregation”) phenomena has been developed to allow for safer EBA operations. To this end, we propose a surface energetics‐based approach. As per the XDLVO theory, free interfacial energy versus distance profiles were calculated for a large combination of model biomass and adsorbent bead types. The energy minima values (absolute value/ U ) obtained for each of the analyzed cases were correlated with the corresponding deposition coefficient values (α). A positive correlation was obtained. It was concluded that total interaction energy U ≤ − 25 to − 50 kT and biomass deposition parameter α ≤ 0.15 would be a safe region for EBA operation; for example, biomass interference can be neglected. Deviation in the correlation was found in such cases where moderate or high cell‐to‐cell aggregation occurs, for example, in hydrophobic interaction systems. In the later cases, laser diffraction studies were necessary to fully characterize the system. These novel tools will help in alleviating the current EBA technical constraints and will guide the design of more efficient adsorbent types.

Utilization of surface energetics approach to Understand protein interaction to ceramic hydroxyapatite

“…Colloidal particle–solid substrate interaction has been widely investigated by the surface thermodynamics approach in various fields of science. It has also been used to explain biomass and bio‐molecules interaction with chromatographic supports in downstream bioprocesses …”

Surface energetics to assess influence of biomass-type and biomass–adsorbent interactions in expanded beds

“…When the interaction is attractive, the net area will be in negative range as opposed to when interactions are repulsive. A detailed explanation of underlying xDLVO calculations has been reported in our previous publications (Fernández Lahore et al 2009 ; Naz 2015 ; Vennapusa 2008c ).…”

“…Zeta potential was calculated from the electrophoretic mobility data according to the Smoluchowski’s equation and all the measurements were done in triplicates. Details of methodology published elsewhere (Fernández Lahore et al 2009 ; Kakarla 2015 ; Vennapusa and Fernandez-Lahore 2010 ).…”

“…For decades, microbiologists and biomedical, environmental, and chemical engineers have invested a lot of effort in understanding and devising a mechanism to control microbial adhesion. Fouling results in the deterioration of equipment and increased maintenance cost (Sanders and Sturman 2005 ; Lappin-Scott and Costerton 1989 ), particularly in expanded bed chromatography (EBA) operations where biomass interactions with the stationary phase result in poor hydrodynamics of the expanded bed column (Fernández Lahore, et al 2009 ). In membrane separation processes, fouling blocks the membrane irreversibly and reduces process efficiency (Kujundzic 2010 ), while in paper industries, these unwanted interactions of fouling agents can cause serious and costly damages to instruments (Simões et al 2010 ).…”

“…The additional AB interaction term appending classical DLVO theory has been shown to explain some of the inconsistencies between classical DLVO predictions and experimental observations (Oss et al 1988 ; Oss 2006 ). Extended DLVO calculations have been validated in a wide variety of colloidal applications (Fernández Lahore et al 2009 ; Oss 2006 ; Vilinska and Rao 2011 ; Fu et al 2015 ; Kakarla 2016 ; Vennapusa 2008b ), and has helped in the understanding of cell–substrate or cell–cell interactions.…”