Surface characterization of polysaccharide scaffolds by inverse gas chromatography regarding application in tissue engineering

Scaffolds are of paramount importance in tissue engineering, providing support for cell attachment and allowing proliferation or differentiation, and production of extracellular matrix. Their surface properties are of major interest since in great part, they determine the biological response to the scaffold. In the present work, three chitosan-based polyelectrolytes scaffolds, namely, 1:1 chitosan-alginate (Chit-Alg), chitosan-pectin (Chit-Pect), and chitosan-carboxymethyl cellulose (Chit-CMC), were studied with regard to their surface properties by inverse gas chromatography. The dispersive component of the surface energy, a measure of the ability of a material to establish Lifshitz Van der Waals interactions, was 47.8 mJ·m⁻² for Chit-Alg, 36.9 mJ·m⁻² for Chit-Pect, and 38.5 mJ·m⁻² for Chit-CMC (at 40°C). All the scaffolds surfaces had an amphoteric character, however, with an apparent prevalence of Lewis acidity over the Lewis basicity. These results have been interpreted in terms of the influence of the different substituent groups in the polysaccharides backbone. The porosities of the Chit-Alg, Chit-Pect, and Chit-CMC scaffolds, assessed by mercury intrusion porosimetry, were found to be of 98%, 96%, and 84%, respectively.