Reticulated PVA Foams: Preparation, Characterization and in vitro Evaluation for Potential 3D Microbiological Culture

Abstract

The development of three-dimensional matrices for microbial cultures is a promising strategy by mimic the natural environments of cells and promoting adhesion, growth and cellular proliferation. In the current study, polyvinyl alcohol (PVA) foams were produced by the combination of gas foaming and freeze-drying for applied as microorganism 3D matrix. The spectra FTIR indicated consume of hydroxyl groups that evidences the crosslinking reaction and promoted increases in thermal stability. Morphological analysis by SEM revealed an interconnected porous structure in the PVA foams. Besides, the crosslinking reaction did not affect pore size and morphology. Meanwhile, cross-linked PVA foam (G-PVAFL) exhibited an increase of compressive modulus and compressive strength. The swelling ratio reached 85% and degradation kinetics of G-PVAFL showed a suitable profile to support microorganism in the biofilm formation. Escherichia coli (Gram-negative bacteria), Staphylococcus aureus (Gram-positive bacteria) and Candida albicans (yeast) were efficiently immobilized in G-PVAFL. In addition, cells morphology were preserved for all species investigated. Besides, Sugar Fermentation Test with Escherichia coli immobilized indicates the preservation of proliferative and metabolic activity. These results indicate that G-PVAFL is suitable as a matrix for 3D microbiological culture.