Diabetic wound (DW) healing is a major clinical challenge due to multifactorial complications leading to prolonged inflammation. Electrospun nanofibrous (NF) membranes, due to special structural features, are promising biomaterials capable to promote DW healing through the delivery of active agents in a controlled manner. Herein, we report a multifunctional composite NF membrane loaded with ZnO nanoparticles (NP) and oregano essential oil (OEO), employing a new loading strategy, capable to sustainedly co-deliver bioactive agents. Physicochemical characterization revealed the successful fabrication of loaded nanofibers with strong in vitro anti-bacterial and anti-oxidant activities. Furthermore, in vivo wound healing confirmed the potential of bioactive NF membranes in epithelialization and granulation tissue formation. The angiogenesis was greatly prompted by the bioactive NF membranes through expression of vascular endothelial growth factor (VEGF). Moreover, the proposed NF membrane successfully terminated the inflammatory cycle by downregulating the pro-inflammatory cytokines interleukin −6 (IL-6) and matrix metalloproteinases-9 (MMP-9). In vitro and in vivo studies revealed the proposed NF membrane is a promising dressing material for the healing of DW.

High moisture permeability, excellent mechanical properties in a wet state, high water-holding capability, and high exudate absorption make bacterial nanocellulose (BNC) a favorable candidate for biomedical device production, especially wound dressings. The lack of antibacterial activity and healing-promoting ability are the main drawbacks that limit its wide application. Pullulan (Pul) is a nontoxic polymer that can promote wound healing. Zinc oxide nanoparticles (ZnO-NPs) are well-known as a safe antibacterial agent. In this study, aminoalkylsilane was chemically grafted on a BNC membrane (A-g-BNC) and used as a bridge to combine BNC with Pul-ZnO-NPs hybrid electrospun nanofibers. FTIR results confirmed the successful production of A-g-BNC/Pul-ZnO. The obtained dressing demonstrated blood clotting performance better than that of BNC. The dressing showed an ability to release ZnO, and its antibacterial activity was up to 5 log values higher than that of BNC. The cytotoxicity of the dressing toward L929 fibroblast cells clearly showed safety due to the proliferation of fibroblast cells. The animal test in a rat model indicated faster healing and re-epithelialization, small blood vessel formation, and collagen synthesis in the wounds covered by A-g-BNC/Pul-ZnO. The new functional dressing, fabricated with a cost-effective and easy method, not only showed excellent antibacterial activity but could also accelerate wound healing.

Alginate (Alg) and bacterial nanocellulose (BNC) have exhibited great potential in biomedical applications, especially wound dressing. Non-toxicity and a moisture-maintaining nature are common features making them favorable for functional dressing fabrication. BNC is a natural biopolymer that promotes major advances to the current and future biomedical materials, especially in a flat or tubular membrane form with excellent mechanical strength at hydrated state. The main drawback limiting wide applications of both BNC and Alg is the lack of antibacterial activity, furthermore, the inherent poor mechanical property of Alg leads to the requirement of a secondary dressing in clinical treatment. To fabricate composite dressings with antibacterial activity and better mechanical properties, sodium alginate was efficiently incorporated into the BNC matrix using a time-saving vacuum suction method followed by cross-linking through immersion in separate solutions of six cations (manganese, cobalt, copper, zinc, silver, and cerium). The results showed the fabricated composites had not only pH-responsive antibacterial activities but also improved mechanical properties, which are capable of acting as smart dressings. All composites showed non-toxicity toward fibroblast cells. Rat model evaluation showed the skin wounds covered by the dressings healed faster than by BNC.

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Background and Objective:: The ratio of live cells to total cells in a sample is a definition for cell viability or cell toxicity. The assessment of the viable cells plays a critical role in all processes of the cell culture workflows. Overall, they are used to evaluate the survival of cells and also to optimize culture or experimental conditions following treatment with different agents or compounds, like during a drug screen. In most cases, the measurement of cell viability is the primary purpose of the experiments, for example, in pharmaceutical studies to evaluate agents' toxicity. Methods:: A literature research was conducted on cell viability assays in MEDLINE (PubMed), Web of Science and Scopus. Results:: There is a wide range of cell viability assays and different parameters such as cost, speed, and complexity of a test effect to determine the choosing method. However each method has some advantages and disadvantages and none of them is not 100% perfect method. Conclusion:: Accordingly, it seems that the simultaneous utility of at least two assays will cover each other disadvantages to demonstrate the effects of different agents on different cell types. For instance, when one assay measures cell metabolic health, the other one checks cells permeability. Therefore by this strategy a researcher can report with more confidence the effective doses of the examined therapeutic agents.

Compositing is an interesting strategy that has always been employed to introduce or enhance desired functionalities in material systems. In this paper, sponges containing polypropylene, lignin, and octavinyl-polyhedral oligomeric silsesquioxane (OV-POSS) were successfully prepared via an easy and elegant strategy called thermally induced phase separation (TIPS). To fully explore the behaviour of different components of prepared sponges, properties were characterized by a thermogravimetric analyser (TGA), differential scanning calorimetry (DSC), Fourier transform infrared measurement (FTIR), and scanning electron microscopy (SEM). Furthermore, wettability properties toward an organic liquid and oil were investigated. The FTIR analysis confirmed the chemical modification of the components. TGA and DSC measurements revealed thermal stability was much better with an increase in OV-POSS content. OV-POSS modified sponges exhibited ultra-hydrophobicity and high oleophilicity with water contact angles of more than 125°. The SEM revealed that POSS molecules acted as a support for reduced surface roughness. Moreover, OV-POSS-based blend sponges showed higher sorption capacities compared with other blend sponges without OV-POSS. The new blend sponges demonstrated a potential for use as sorbent engineering materials in water remediation.

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: Bacterial nanocellulose (BNC) is one of the natural biopolymers with unique features, the most important of which are nontoxicity, biocompatibility, high tensile profile, nanofiber structure, and purity. The current review aimed to summarize the latest development in BNC-based biomaterials in cancer drug delivery. The original articles were found by searching key databases including PubMed, Scopus, and Web of Scientific and using key terms such as “bacterial nanocellulose OR bacterial cellulose OR BNC” AND “cancer OR carcinoma OR tumor”. The obtained data were in a wide timeframe and the English language. Totally, 350 articles were found from the three main databases (i.e., 106, 251, and 173 articles from PubMed, Scopus, and the Web of Science, respectively). In general, 32 articles met the inclusion criteria after duplicate removal and screening according to the aim of the present review study. In this review study, different applications of the bacterial nanocellulose were considered for cancer drug delivery in addition to describing advanced methods that may be applied to improve therapeutic potency while reducing the adverse effects of chemodrugs by decreasing their dosages. The high ratio of the surface area-to-volume and easy modifications of their chemical components lead BNC potential use as an appropriate matrix structure for the binding and controlled release of various pharmaceutical agents, specifically for topical or transdermal administrations. In addition, BNC-based products regulate the release of hydrophobic and hydrophilic compounds, therefore, provide appropriate materials related to cancer drug delivery. However, undoubtedly, further developments of BNC-based products as cancer drug delivery systems require more extensive investigations.