J. Phys. II France
Volume 3, Numéro 5, May 1993
Page(s) 611 - 624
DOI: 10.1051/jp2:1993155
J. Phys. II France 3 (1993) 611-624

3D analysis of gelatin gel networks from transmission electron microscopy imaging

M. Djabourov1, N. Bonnet2, H. Kaplan2, N. Favard3, P. Favard3, J. P. Lechaire3 and M. Maillard3

1  Ecole de Physique et Chimie, CNRS URA 857, 10 rue Vauquelin, 75231 Paris Cedex 05, France
2  Unité INSERM 314, Université de Reims, 21 rue Clément Ader, 51100 Reims, France
3  Centre de Biologie Cellulaire CNRS, 67 rue Maurice Günsbourg, 94205 Ivry-sur-Seine Cedex, France

(Received 29 December 1992, accepted in final form 11 February 1993)

This paper presents a quantitative analysis of the structural parameters of gelatin gel networks derived from transmission electron micrographs. The network gel replicas were obtained by a quick-freezing, deep-etching and rotary replication method adapted to the study of fragile physical networks by Favard P. et al. (Biol. Cell 67 (1989) 201-207). Stereo electron micrographs were taken by tilting the replicas at increasing angles between - 35 to + $30^\circ$. A 3D reconstruction of the filamentous network was performed by stereoscopic and tomographic procedures. These procedures allowed us to measure the thicknesses of the replicas. The average length of filaments (triple helices) per unit volume and the average distance between filaments (mesh sizes of the networks) were derived for two polymer concentrations ( $c=2~\%$ and $c=10~\%$). The results are in full agreement with optical rotation and small-angle neutron scattering measurements.

82.70G - 61.16D

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