Preparation and characterization of a bacterial cellulose/silk fibroin sponge scaffold for tissue regeneration

Abstract

Bacterial cellulose (BC) and silk fibroin (SF) are natural biopolymers successfully applied in tissue engineering and biomedical fields. In this work nanocomposites based on BC and SF were prepared and characterized by scanning electron microscopy (SEM), infrared spectroscopy (FT-IR), X-ray diffraction (XRD) and thermogravimetric analysis (TGA). In addition, the investigation of cytocompatibility was done by MTT, XTT and Trypan Blue dye technique. Cellular adhesion and proliferation were detected additionally. The evaluation of genotoxicity was realized by micronucleus assay. In vitro tests showed that the material is non-cytotoxic or genotoxic. SEM images revealed a greater number of cells attached at the BC/SF:50% scaffold surface than the pure BC one, suggesting that the presence of fibroin improved cell attachment. This could be related to the SF amino acid sequence that acts as cell receptors facilitating cell adhesion and growth. Consequently, BC/SF:50% scaffolds configured an excellent option in bioengineering depicting its potential for tissue regeneration and cultivation of cells on nanocomposites.

Fabrication of functionalized citrus pectin/silk fibroin scaffolds for skin tissue engineering

“…PEC dissolution resulted in a structural deformity and SF was partially released into solution. In a similar study, bacterial cellulose/SF sponges were degraded 50% in lysozyme solution after 24 h. In agreement with the literature, ∼47% weight loss was observed which was higher than the weight loss observed in PBS . The enzyme activity in skin has been reported to be around 2.5 μg/mL, which is lower than lysozyme concentration used in our enzymatic degradation study.…”

Bacterial cellulose as a material for wound treatment: Properties and modifications. A review

“…collagen) (Saska et al, 2012) Ethyl-, propyl-, i-propyl-, nbutyl BC derivatives with better solubility in low polar solvents (Lin et al, 2013b) Improved water solubility (Geyer et al, 1994) Improved protein adsorption (Lin et al, 2015) Hydrophobizat ion of BC surface Active site for further modifications Carbon reactivity: C(6)>>C (2) (Luo et al, 2014b) Shaking conditions result in thinner and longer BC fibers (Mohite and Patil, 2014) 50% loss in fiber diameter (Grande et al, 2009a) Increased microfibril diameter (Ha et al, 2011) Composite with suitable electrical properties (Luo et al, 2014a) Scaffold with improved biocompatibility for bone regeneration (Grande et al, 2009a) Material adsorbent for heavy metals Material with high efficiency in wound healing (Wiegand et al, 2006) Promising material for wound healing therapy (Fu et al, 2014;Phisalaphong and Jatupaiboon, 2008) Composites with great antimicrobial activity ( grafting of methyl terminated octadecyltrichlorosilane (Taokaew et al, 2015) grafting of amine terminated 3-aminopropyltriethoxysilane (Taokaew et al, 2015) RGD peptides:  Attachment through cellulose binding modules )  Attachment through xyloglucan binding modules IKVAV peptide sequence:  Attachment through carbohydrate binding modules (Pertile et al, 2012) ɛ-Polylysine:  Penetration of a solution into the BC matrix followed by crosslinking with procyanidins (Gao et al, 2011) Poly-L-lysine hydrobromide:  Penetration of a solution into the BC matrix (Culebras et al, 2015) Macrophagestimulating protein:  Penetration of a solution into the BC matrix (Zhao et al, 2015) Silk fibroin:  Penetration of a solution into the BC matrix (Olivera Barud et al, 2015) Growth factors:  Penetration of a solution into the BC matrix Shi et al, 2012b) Collagen:  Penetration of a solution into the BC matrix Culebras et al, 2015)<...>…”

“…Its impregnation into the BC structure was shown to result in a composite with the significantly increased adhesion, spreading and proliferation characteristics towards Chinese hamster fibroblasts and L929 cells. The absence of the cytotoxicity indicates safety of BC/silk fibroin composites for biomedical applications (Oliveira Barud et al, 2015). Macrophage-stimulating protein (MSP) is known to accelerate the wound healing processes by inducing the keratinocytes proliferation and prevention of the epithelial cells apoptosis (Zhao et al, 2015).…”

Abu Zenima synthetic zeolite for removing iron and manganese from Assiut governorate groundwater, Egypt

“…(2) The growth of iron bacteria on sand filters or valves, cause water discoloration and increases its turbidity (Oliveira Barud et al 2015;Shankar and Rhim 2015). Therefore, ion exchange method is considered one of the most promising methods for removing iron and manganese ions from the groundwater, as their concentration does not exceed 5 mg/L (Bilal et al 2013;Yang et al 2015).…”