Antimicrobial and Wound-Healing Activities of Graphene-Reinforced Electrospun Chitosan/Gelatin Nanofibrous Nanocomposite Scaffolds.

This study aims at preparing electrospun chitosan/gelatin nanofiber scaffolds reinforced with different amounts of graphene nanosheets to be used as antibacterial and wound-healing scaffolds. Full characterization was carried out for the different fabricated scaffolds before being assessed for their antimicrobial activity against Escherichia coli and Staphylococcus aureus, cytotoxicity, and cell migration capacity. Raman and transmission electron microscopies confirmed the successful reinforcement of nanofibers with graphene nanosheets. Scanning electron microscopy and porosity revealed that nanofibers reinforced with 0.15% graphene nanosheets produced the least diameter (106 ± 30 nm) and the highest porosity (90%), in addition to their good biodegradability and swellability. However, the excessive increase in graphene nanosheet amount produced beaded nanofibers with decreased porosity, swellability, and biodegradability. Interestingly, nanofibers reinforced with 0.15% graphene nanosheets showed E. coli and S. aureus growth inhibition percents of 50 and 80%, respectively. The cell viability assay showed no cytotoxicity on human fibroblasts when cultured with either unreinforced or reinforced nanofibers. The cell migration was higher in the case of reinforced nanofibers when compared to the unreinforced nanofibers after 24 and 48 h, which is substantially associated with the great effect of the graphene nanosheets on the cell migration capability. Unreinforced and reinforced nanofibers showed cell migration results up to 93.69 and 97%, respectively, after 48 h.

Targeted doxorubicin delivery and release within breast cancer environment using PEGylated chitosan nanoparticles labeled with monoclonal antibodies.

Breast cancer has been one of the top chronic and life-threatening diseases worldwide. Nano-drug therapeutic systems have proved their efficacy as a selective treatment compared to the traditional ones that are associated with serious adverse effects. Here, biodegradable chitosan nanoparticles (CSNPs) were synthesized to provide selective and sustained release of doxorubicin (DOX) within the breast tumor microenvironment. CSNPs surface was modified using Polyethylene glycol (PEG) to enhance their blood circulation timing. To provide high drug selectivity, CSNPs functionalized with two different types of breast cancer-specific monoclonal antibodies (mAb); anti-human mammaglobin (Anti-hMAM) and anti-human epidermal growth factor (Anti-HER2). Anti-hMAM PEGylated DOX loaded CSNPs and Anti-HER2 PEGylated DOX loaded CSNPs nano-formulations were the most cytotoxic against MCF-7 cancer cells than L-929 normal cells compared to free DOX. Finally, we believe that dose-dependent system toxicity of freely ingested DOX can be managed with such targeted nano-formulated drug delivery platforms.

Fabrication of Nanofibrous/Xerogel Layer-by-Layer Biocomposite Scaffolds for Skin Tissue Regeneration: In Vitro Study.

Skin burn wounds are a crucial issue that could reduce life quality. Although numerous effective skin products have invaded the biomedical market, most of them still demonstrate some limitations regarding their porosity, swelling and degradation behaviors, antibacterial properties, and cytotoxicity. Thus, the aim of this study is to fabricate novel trilayered asymmetric porous scaffolds that can mimic the natural skin layers. In particular, the fabricated scaffold constitutes an upper electrospun chitosan-poly(vinyl alcohol) layer and a lower xerogel layer, which is made of effective skin extracellular matrix components. Both layers are fixed together using fibrin glue as a middle layer. The results of this study revealed promising scaffold swelling capability suitable for absorbing wound exudates, followed by a constant degradable weight over time, which is appropriate for a burn wound environment. Scanning electron microscopy images revealed an average pore diameter in the range of 138.39-170.18 nm for the cross-linked electrospun mats and an average pore size of 2.29-30.62 µm for the fabricated xerogel layers. This further provided an optimum environment for fibroblast migration and proliferation. The electrospun nanofibrous layer was examined for its antibacterial properties and showed expressive complete bacterial inhibition against Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacterial strains (log reduction = 3 and 2.70, respectively). Next, mouse embryonic fibroblast cytotoxicity and migration rate were investigated against the developed asymmetrical composite to assess its biocompatibility. Tissue culture experiments demonstrated significant cell proliferation and migration in the presence of the constructed scaffold (P < 0.0001). A complete wound closure was observed in vitro in the presence of the three scaffold asymmetrical layers against the mouse embryonic fibroblast. The results of this study proved superior biological characteristics of the innovative asymmetrical composite that could further replace the burned or damaged skin layers with promising potential for clinical applications.

Essential oil loaded pectin/chitosan nanoparticles preparation and optimization via Box-Behnken design against MCF-7 breast cancer cell lines.

In the continuous search for effective cancer treatments, we here report a novel anticancer nanoparticulate system composed of jasmine oil (JO), an essential oil with proven anticancer activity and pectin/chitosan composite nanoparticles (Pec/CS NPs) as encapsulating materials to overcome JO's solubility and sensitivity problems using a green ionotropic gelation method. Pec/CS/JO NPs were formulated using Box-Behnken design (BBD) to estimate the interactions and effects of studied formulation variables on particle size, zeta potential and encapsulation efficiency to develop an optimized Pec/CS nanoformulation. The nano-encapsulation system preserved the consistency of total phenolic contents in JO and amended its thermal stability by 1.64 fold. The antioxidant potency of JO was enhanced after encapsulation by 96.28%. Consequently, the cytotoxic activity of bare Pec/CS NPs, pure JO and encapsulated JO in Pec/CS NPs against (MCF-7) breast cancer cells and (L-929) normal cells was evaluated using MTT assay. Encapsulated JO was more potent than pure JO with ≈13 fold improvement in anticancer activity, whereas the cell viability of normal cells wasn't affected but was rather enhanced when treated with Pec/CS NPs.