Surface energetics to assess biomass attachment onto immobilized metal-ion chromatography adsorbents in expanded beds

Abstract

^Äëíê~Åí= Cell-to-support interaction and cell-to-cell agglomeration phenomena have been studied in a model system composed of intact yeast cells and Chelating-Streamline TM adsorbents. Biomass components and beaded adsorbents were mainly characterized by contact angle determinations with three diagnostic liquids. Complementarily, zeta potential measurements were performed. These experimental values were employed to calculate free energy of interaction versus distance profiles in aqueous media. The effect of immobilized metal-ion type and buffer pH on the interaction energy was evaluated. Calculations indicated that moderate interaction between cell particles and adsorbent beads can develop due to the presence of Cu 2+ ions onto the solid phase. The strength of interaction increased with buffer pH, within the range 6.0 to 8.3 ÉKÖK secondary energy pockets increased from |15| to |60| âT. Cell-to-cell secondary energy minimum was ≥ |14| âT showing lowto-moderate tendencies to aggregate, particularly at pH ≥ 8. Extended DLVO predictions were generally confirmed by biomass deposition experiments. However, an exception was found when working with immobilized Cu 2+ at pH 8 since yeast cells were able to sequestrate such immobilized ions. Therefore, lower-than-expected values for the depositions coefficient (α) were observed. Understanding biomass attachment onto Chelating supports can help in better design and operate expanded bed adsorption of bioproducts. © KSBB hÉóïçêÇëW= ÇáêÉÅí= ëÉèìÉëíê~íáçåI= Äáçã~ëë= ÇÉéçëáíáçåI= ëìêÑ~ÅÉ= ÉåÉêÖÉíáÅëI= ÄáçéêçÅÉëë= ÇÉëáÖåI= áããçÄáäáòÉÇ= ãÉí~ä=~ÑÑáåáíó= ÅÜêçã~íçÖê~éÜóI=Éñé~åÇÉÇ=ÄÉÇ=~Çëçêéíáçå G`çêêÉëéçåÇáåÖ=~ìíÜçê=

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

“…Table shows that the ceramic hydroxyapatite presents a very low surface energy, i.e. 28.6 mJ m ‐2 compared with other chromatographic materials, which showed a range of total surface energies from ∼40–60 mJ m ‐2 . It is a common observation that the high contact angle values result in lower surface energy values .…”

“…According to the results presented in this work, the tool proposed enables an understanding of the chromatographic behavior of proteins, as presented for the hydrophobic supports . An extension of the same method has previously been utilized to predict colloidal particle deposition onto solid surfaces …”

“…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 …”

Growth-dependent surface characteristics of Hansenula Polymorpha: implications for expanded bed adsorption chromatography

“…The surface energy parameters calculated from Equation 3, as well as the zeta potentials of involved surfaces along with the Debye-Hückel length (Equation 4) are consequently used to calculate U LW , U AB , and U EL interaction energy components using the standard equations of xDLVO theory that were adapted for biomass-adsorbent systems and which are mentioned in several previous reports [17,27,36,37].…”

Reversible immobilization of uricase on conductive polyaniline brushes grafted on polyacrylonitrile film

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