Open AccessSurface Energetics to Assess Microbial Adhesion onto Fluidized Chromatography Adsorbents
Author(s) -
Vennapusa R. R.,
Binner S.,
Cabrera R.,
FernandezLahore M.
Publication year - 2008
Publication title -
engineering in life sciences
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.547
H-Index - 57
eISSN - 1618-2863
pISSN - 1618-0240
DOI - 10.1002/elsc.200800027
Subject(s) - adsorption , hydrophilic interaction chromatography , chemistry , agarose , interaction energy , zeta potential , ion chromatography , contact angle , chemical engineering , surface charge , chromatography , adhesion , matrix (chemical analysis) , organic chemistry , high performance liquid chromatography , molecule , nanoparticle , engineering
Cell‐to‐support interaction and cell‐to‐cell aggregation phenomena have been studied in a model system composed of intact yeast cells and agarose‐based chromatography adsorbent surfaces. Biomass components and beaded adsorbents were characterized by contact angle determinations with three diagnostic liquids and, complementarily, by zeta potential measurements. Such experimental characterization of the interacting surfaces has allowed the calculation of interfacial free energy of interaction in aqueous media vs. distance profiles. The extent of biomass adhesion was inferred from calculations performed assuming standard chromatographic conditions, but different adsorption modes. Several stationary support/mobile phase systems were considered, i.e., ion exchange, hydrophobic interaction, and pseudo‐affinity. The calculated interaction energy minima revealed marginal attraction between cells and cation exchangers or agarose‐matrix beads ( U ≤ |10–20| kT) but strong attraction with anion exchangers ( U ≥ |200–1000| kT). Other systems including hydrophobic interaction and chelating beads showed intermediate energy minimum values ( U <$>\approx<$> |40–100| kT) for interaction with biological particles. However, the calculations also showed that working conditions in the presence of salt can promote cell aggregation apart from cell‐to‐support interaction. Predictions based on the application of the XDLVO approach were confirmed by independent experimental methods, e.g., biomass deposition experiments and laser diffraction spectroscopy. The understanding of biomass attachment onto chromatographic supports can help in alleviating process limitations normally encountered during direct (primary) sequestration of bioproducts.