Biomaterials for in vivo application should induce positive interaction with various histocytes and inhibit bacteria inflection as well. Cells and/or bacteria response to the extracellular environment is therefore the basic principle to design the biomaterials surface in order to induce the specific biomaterial–biological interaction. Polyhydroxyalkanoate (PHAs) are of growing interests because of their natural origin, biodegradability, biocompatibility, and thermoplasticity; however, quite inert and intrinsic hydrophobic characteristics have hindered their extensive usage in medical applications. Surface modification of PHAs tailors the chemistry, wettability, and topography without altering the bulk properties, and introduces specific proteins/peptides and/or antibacterial agents to mediate cell–matrix interactions. This review describes the recent developments on the surface modification of PHAs to construct cell compatible and antibacterial surfaces.
Biological glue (bioglue) neatly and noninvasively seals wound against external tension and holds great potential in scarless wound healing. Nevertheless, the current bioglues lack regulating inflammatory cytokines and transforming growth factor-β1 (TGF-β1), two other key factors for scar formation. Herein, a new bioglue, termed LA-glue, was developed by thermal-initiated polymerization of the aqueous dispersion of lipoic acid (LA) and its sodium salt. When contacting to tissue, LA-glue would firmly seal the wound by its high-density carboxyl groups. Importantly, the indwelling LA-glue would gradually degrade to LA, a B vitamin which could reeducate overexpressed pro-inflammatory cytokines and TGF-β1 to normal levels. In vivo results demonstrated that the LA-glue treated wound not only possessed an appearance indistinguishable from normal skin but had tensile strength and hair follicles restored to those of healthy skin. The simple and safe LA-glue is the first to address the three key factors of scar formation, i.e., external tension, excessive inflammatory response, and uncontrolled TGF-β1 expression, and has great promise in clinical settings.
Cell-loaded carboxymethylcellulose (CMC) microspheres were generated via a flow focusing microfluidic device, with a final aim to obtain viable ATDC5 aggregates with sustained proliferation capacity. We synthesized various CMC with phenolic groups (CMC-Ph) and demonstrated that high CMC-Ph molecular weight, high CMC-Ph concentration (>0.8 g/ml) or long culturing period had obvious inhibition effect on ATDC5 proliferation, but low horseradish peroxidase concentration (HRP, <0.4 mg/ml) did not. CMC-Ph gels being obtained through HRP/HO reaction showed an enhancing strength and decreasing break stain as the molecular weight of CMC-Ph increased, along with a decreasing gelation time. The microfluidics-based synthesis of cell-loaded microspheres with great design flexibilities was achieved using CMC-Ph with weight-average molecular weight of 1.0 × 10. ATDC5 cells were viable up to 41 days of culture and proliferated gradually with increasing culture time. High cell density in CMC-Ph solution and high fetal bovine serum concentration in culture medium were prone to forming cell aggregates. Isolated cells from the microspheres showed the typical spherical morphology of undifferentiated ATDC5. Therefore, CMC-Ph microspheres might be used as cell aggregates depots to study cell-cell or cell-biomaterials functions for tissue engineering applications.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.