Investigations of cell immobilization in alginate: rheological and electrostatic extrusion studies

✍ Scribed by Verica Manojlovic; Jasna Djonlagic; Bojana Obradovic; Viktor Nedovic; Branko Bugarski

• Publisher: Wiley (John Wiley & Sons)
• Year: 2006
• Tongue: English
• Weight: 135 KB
• Volume: 81
• Category: Article
• ISSN: 0268-2575
• DOI: 10.1002/jctb.1465

✦ Synopsis

Abstract

In this study, the process of electrostatic extrusion as a method for cell immobilization was investigated. We have assessed the effects of concentrations of yeast cells (as a model cell type) and Na alginate on the size of the resulting microbeads and attempted to rationalize the obtained findings by rheological characterization of the cell–alginate suspensions. Under the investigated conditions, microbeads, 50–600 µm in diameter, were produced and the increase in both alginate and cell concentrations resulted in larger microbeads with their sizes having higher standard deviations. Rheological characterization revealed non‐Newtonian, pseudoplastic behavior of cell–alginate suspensions with higher viscosities at higher alginate concentrations. However, the presence of cells even at high concentrations (5 × 10^8^ and 1 × 10^9^ cells mL^−1^) did not significantly affect the rheological properties of the Na alginate solution. Finally, we have investigated the kinetics of alginate gelation with respect to the quantity of Ca^2+^ ions and the presence of cells. The molar ratio of α‐L‐guluronic acid units to Ca^2+^ ions of 4:1 provided complete crosslinking. The presence of cells decreased the rate of network formation as well as the strength of the obtained Ca alginate hydrogel. Copyright © 2006 Society of Chemical Industry