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Electrochemically Assisted Encapsulation of Bacteria in Sol-Gel Thin Films
|Wissam Ghach , Mathieu Etienne , Frédéric Jorand , Alain Walcarius|
Laboratoire de Chimie Physique et Microbiologie pour l'Environnement (LCPME), 405, rue de Vandoeuvre, Nancy 54600, France
|Life-span viability accompanied with preserved activity of micro-organisms in solid support has gained considerable interests for bioelectrochemical applications including biofuel cells and biosensors for environmental monitoring. Sol-gel technology has proved its suitable environment for living cells entrapment and ensured their stability and activity enhancement better than free living cells . The development of the electrochemically assisted deposition of sol-gel at the end of the nineties  has opened a larger window for bioencapsulation process in thin sol-gel films by using the electrochemical methods . The Electrochemically assisted deposition has several advantages compared to other sol-gel methods that are based on solvent evaporation (spin-, dip-, spray-coatings). It exhibits the ability of film deposition on small electrodes (ultramicroelectrode) or non-flat supports, in-addition to the film deposition on conducting supports for useful electrochemical applications and monitoring. Moreover, the possibility of porosity control by using the template approach  and thickness control facilitates the interactions of trapped living cells with the surrounding environment for fluorescent and environmental analysis.|
This communication intends to show some recent developments on sol-gel bioencapsulation using electrochemically assisted deposition applied to the immobilization of bacteria. The incorporation of biocompatible organic polymers to the inorganic sol-gel source has proved the mechanical enhancement of sol-gel deposition and stability. Furthermore, additional disaccharide has provided a more hydrophilic environment which is critical for bioencapsulation of micro-organisms in thin sol-gel film. This hybrid composition of sol-gel appeared to be critical for the long-term viability of trapped bacteria according to the bacterial membrane integrity studied by Live/Dead BacLight viability assay. It proved a better long-term stability of the bacterial membrane integrity than that of inorganic composition of sol-gel . Perspectives of bacterial respiration analysis and bioencapsulation of other complex biological objects with the electrochemically assisted methodology will be discussed later on. D. Avnir, T. Coradin, O. Lev, J. Livage, J. Mater. Chem., 2006, 16, 1013.
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Presentation: Poster at SMCBS'2011 International Workshop, by Wissam Ghach
See On-line Journal of SMCBS'2011 International Workshop
Submitted: 2011-08-31 15:49 Revised: 2011-08-31 16:26