Physical characteristics and cell-adhesive properties of in vivo fabricated bacterial cellulose/hyaluronan nanocomposites

Abstract: BC membranes (pellicles) generated by Gluconacetobacter hansenii (G. hansenii) are promising biomaterials owing to their outstanding biocompatible properties. Recently, specific demands for biomedical applications of BC have increased owing to its excellent mechanical properties. Although many techniques have been developed to improve the biofunctional properties of BC pellicles, such modifications remain limited owing to technical difficulties in the modulation of complex biosynthetic processes. Therefore, we previously developed an in vivo modification technique to produce nanocomposite pellicles composed of BC and HA (in vivo BC/HA), which are directly secreted from genetically engineered G. hansenii. In the present study, the HA extractability and content rate, physical characteristics, and cytocompatibility of in vivo BC/HA have been investigated in comparison to conventional in situ BC/HA and native BC pellicle. The results suggested that HA more strongly adsorbed to the solid BC surface of in vivo BC/HA than that of in situ BC/HA, which possibly affected the dynamic viscoelastic characteristics. In vivo BC/HA exhibited a relatively lower value of 7.5 MPa as storage elastic modulus (E’), whereas in situ BC/HA yielded the highest E’ of 15.6 MPa in comparison to 11.4 MPa as E’of native BC. Although the HA content of in vivo BC/HA (95 μg/g) was indicated lower than in situ BC/HA (300 μg/g), the former showed two times higher ability in human epidermal cell adhesion. These results indicate the great potential of in vivo modification to expand the usefulness of BC-based biomaterials. Graphical Abstract: [Figure not available: see fulltext.]