In Vitro Studies of Bacterial Cellulose and Magnetic Nanoparticles Smart Nanocomposites for Efficient Chronic Wounds Healing

Abstract

The quality of life of patients with chronic wounds can be extremely poor and, therefore, over the past decades, great efforts have been made to develop efficient strategies to improve the healing process and the social impact associated with these conditions. Cell based therapy, as a modern tissue engineering strategy, involves the design of 3D cell-scaffold bioconstructs obtained by preseeding drug loaded scaffolds with undifferentiated cells in order to achieve in situ functional de novo tissue. This paper reports on the development of bionanocomposites based on bacterial cellulose and magnetic nanoparticles (magnetite) for efficient chronic wounds healing. Composites were obtained directly in the cellulose bacterial culture medium by dispersing various amounts of magnetite nanoparticles during the biosynthesis process. After purification and drying, the membranes were characterized by Raman spectroscopy and X-ray diffraction to reveal the presence of magnetite within the bacterial cellulose matrix. Morphological investigation was employed through SEM and TEM analyses on bionanocomposites. The biocompatibility of these innovative materials was studied in relation to human adipose derived stem cells in terms of cellular morphology, viability, and proliferation as well as scaffolds cytotoxic potential.

Figure 1

Raman spectra of pure BC, magnetite, and BC/magnetite 5% membranes.

Figure 2

XRD diffractograms of pure BC, magnetite, and BC/magnetite composites.

Figure 3

SEM microphotographs of pure magnetite nanoparticles (a), bacterial cellulose (b), nanocomposite with 1% magnetite (c), and 5% magnetite (d).

Figure 4

TEM and SAED images of pure magnetite nanoparticles.

Figure 5

TEM microphotographs of bacterial cellulose.

Figure 6

TEM and HR-TEM images of BC/magnetite membranes with 5% MNP content.

Figure 7

Confocal fluorescence microscopy micrographs of hASCs actin filaments network (red fluorescence) in hASCs/BC, hASCs/BC/magnetite 1%, hASCs/BC/magnetite 2%, and hASCs/BC/magnetite 5%, DAPI-stained nuclei are blue.

Figure 8

Confocal fluorescence microscopy micrographs revealing live and dead cells on BC, BC/magnetite 1%, BC/magnetite 2%, and BC/magnetite 5%, after 24 h of culture.

Figure 9

Quantification of (a) hASCs viability on pure BC, BC/magnetite 1%, BC/magnetite 2%, and BC/magnetite 5% nanocomposites, as revealed by MTT test at 24 h and 5 days postseeding. [^∗∗∗ p < 0.001 (hASCs/BC versus hASCs/BC/magnetite 5% nanocomposites) and ^### p < 0.001 (hASCs/BC 24 h versus hASCs/BC 5 days; hASCs/BC/magnetite 1% 24 h versus hASCs/BC/magnetite 1% 5 days; hASCs/BC/magnetite 2% 24 h versus hASCs/BC/magnetite 2% 5 days; hASCs/BC/magnetite 5% 24 h versus hASCs/BC/magnetite 5% 5 days)] and (b) pure BC, BC/magnetite 1%, BC/magnetite 2%, and BC/magnetite 5% nanocomposites' cytotoxic potential effect on hASCs after 24 h and 5 days of culture as revealed by LDH assay.