CARS and SHG microscopy for the characterization of bacterial cellulose
Konferensbidrag (offentliggjort, men ej förlagsutgivet), 2009

We have developed a protocol employing dual-mode non-linear microscopy for the monitoring of the biosynthesis of bacterial cellulose at a single-fiber level, with the fundamental aim to achieve a product with material properties similar to those of human blood vessels. Grown in a tubular geometry it could then be used as a natural and biocompatible source of replacement tissue in conjunction with cardiovascular surgery. The bacteria (Acetobacter xylinum) were selectively visualized based on the CH2 vibration of its organic macromolecular contents by the Coherent Anti-Stokes Raman Scattering (CARS) process and, simultaneously, the non-centrosymmetrically ordered, birefringent cellulose fibers were depicted by the Second Harmonic Generation (SHG) process. This dual-channel detection approach allows the monitoring of cellulose-fiber formation in vivo and to determine the influence of e. g. different growth conditions on fiber thickness and orientation, their assembling into higher-order structures and overall network density. The bacterial and fiber distributions were monitored in a simple microscope cultivation chamber, as well as in samples harvested during the actual fermentation process of tubular cellulose grafts. The CARS and SHG co-localization images reveal that highest bacterial population densities can be observed in the surface regions of the cellulose tissue, where the primary growth presumably takes place. The cellulose network morphology was also compared with that of human arteries and veins, from which we conclude that the cellulose matrix is comparatively homogeneous in contrast to the wavy band-like supra-formations of collagen in the native tissue. This prompts for sophisticated fermentation methods by which tunnels and pores of appropriate sizes and shapes can be introduced in the cellulose network in a controllable way. With this protocol we hope to contribute to the fundamental knowledge required for optimal production of bioengineered cellulose tissues, eventually being available for clinical use.

Acetobacter xylinum

Tissue

engineering

Bacterial cellulose

Coherent anti-Stokes Raman Scattering

Second

Non-linear microscopy

Harmonic Generation

Författare

Annika Enejder

Chalmers, Kemi- och bioteknik, Molekylär mikroskopi

Christian Brackmann

Chalmers, Kemi- och bioteknik, Molekylär mikroskopi

Aase Katarina Bodin

Chalmers, Kemi- och bioteknik, Polymerteknologi

Madeleine Åkeson

Chalmers, Kemi- och bioteknik, Molekylär mikroskopi

Paul Gatenholm

Chalmers, Kemi- och bioteknik, Polymerteknologi

Progress in Biomedical Optics and Imaging - Proceedings of SPIE

16057422 (ISSN)

Vol. 7183 71830U

Styrkeområden

Livsvetenskaper och teknik

Materialvetenskap

Ämneskategorier

Kemi

DOI

10.1117/12.809659

ISBN

978-0-8194-7429-2

Mer information

Skapat

2017-10-08