Morrissey Kathryn L, He Chunlin, Chapman Rebeccah Z, Żołnierowski Lucjan, Stoykovich Mark P
Department of Chemical and Biological Engineering, University of Colorado at Boulder, Boulder, CO 80309, USA.
Department of Chemical and Biological Engineering, University of Colorado at Boulder, Boulder, CO 80309, USA.
Acta Biomater. 2016 Aug;40:192-200. doi: 10.1016/j.actbio.2016.03.042. Epub 2016 Apr 1.
The efficient concentration and separation of microorganisms from dilute culture suspensions is crucial to the success and productivity of many biotechnological processes. This article presents the design and characterization of polyamphoteric flocculants with a tunable, zwitterionic character for the enhanced separation of biocolloidal suspensions of yeast, wastewater, microalgae, and potentially other cellular systems. The polyamphoteric flocculants have overall molecular charges dependent upon the system pH, thereby providing a strong electrostatic attraction to the diverse but predominantly negatively-charged cellular surfaces of the biological suspensions. The polyamphoteric flocculants with tailored charge character are shown to have higher flocculation efficiencies than comparable cationic polyelectrolytes, and have an enhanced ability to 1) adsorb to the diverse range of charge character in cellular suspensions, 2) operate over an extended range of suspension pHs, and 3) operate at lower flocculant concentrations. These enhanced flocculation properties are shown to arise, perhaps counterintuitively, due to interactions between the negatively-charged functionality on the flocculant and the predominantly negatively-charged biocolloids.
This article presents the design and characterization of polyamphoteric flocculants for the separations of biocolloidal suspensions of importance in the production of biopharmaceuticals, microalgal cultures for nutraceuticals and biofuels, and wastewater treatment. The polyamphoteric flocculants consist of tunable, mixed charges dependent upon system pH, thereby providing strong electrostatic attraction to the diversely-charged surfaces of cellular suspensions. Enhanced flocculation efficiencies are achieved, as compared to cationic polyelectrolyte flocculants, and result from the ability of polyampholytes to adsorb to a diverse range of charge character and operate over an extended range of pH conditions.
从稀释的培养悬浮液中高效浓缩和分离微生物对于许多生物技术过程的成功和生产力至关重要。本文介绍了具有可调节两性离子特性的聚两性电解质絮凝剂的设计与特性，用于增强酵母、废水、微藻以及潜在的其他细胞系统的生物胶体悬浮液的分离。聚两性电解质絮凝剂的整体分子电荷取决于系统pH值，从而对生物悬浮液中多样但主要带负电荷的细胞表面提供强大的静电吸引力。具有定制电荷特性的聚两性电解质絮凝剂显示出比同类阳离子聚电解质更高的絮凝效率，并且具有增强的能力：1）吸附到细胞悬浮液中各种电荷特性上；2）在较宽的悬浮液pH范围内运行；3）在较低的絮凝剂浓度下运行。这些增强的絮凝特性表明，可能与直觉相反，是由于絮凝剂上带负电荷的官能团与主要带负电荷的生物胶体之间的相互作用引起的。
本文介绍了用于分离生物胶体悬浮液的聚两性电解质絮凝剂的设计与特性，这些悬浮液在生物制药生产、用于营养保健品和生物燃料的微藻培养以及废水处理中具有重要意义。聚两性电解质絮凝剂由取决于系统pH值的可调节混合电荷组成，从而对细胞悬浮液中带不同电荷的表面提供强大的静电吸引力。与阳离子聚电解质絮凝剂相比，实现了更高的絮凝效率，这是由于聚两性电解质能够吸附到各种电荷特性上并在较宽的pH条件范围内运行。
