The development of food packaging possessing bioactivities which could extend the shelf life of food has gained increased interest in recent years. In this study, gelatin nanofibers with encapsulated angelica essential oil (AEO) were fabricated via electrospinning. The morphology of gelatin/AEO nanofibers was examined by scanning electron microscopy (SEM) and the addition of AEO resulted in the increase of fiber diameter. The proton nuclear magnetic resonance (1H-NMR) spectra were measured to confirm the presence of AEO in nanofibers. The hydrophobic property of gelatin nanofibers was also found to be improved with the addition of AEO. The nanofibers incorporated with AEO showed significant antioxidant activity and inhibitory effect against both Gram-negative and Gram-positive bacteria in a concentration dependent manner. Furthermore, the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay demonstrated that the developed gelatin/AEO nanofibers revealed no cytotoxicity effect. Thus, gelatin nanofibers incorporated with AEO can be used as potential food packaging.

Implanted scaffold or bone substitute is a common method to treat bone defects. However, the possible bone infection caused by orthopaedic surgery has created a challenging clinical problem and generally invalidate bone repair and regeneration. In this study, a poly (ε-caprolactone) (PCL)/polyethylene glycol (PEG)/roxithromycin (ROX) composite scaffold was prepared via melt electrohydrodynamic (EHD) 3D printing. Fourier transform infrared spectroscopy (FTIR) spectroscopy was performed to verify the existence of PEG and ROX in the scaffolds. By water contact angle measurement, the addition of both PEG and ROX was found to improve the hydrophilicity of the scaffolds. By in vitro drug release assay, the PCL/PEG/ROX scaffolds showed an initial burst drug release and subsequent long-term sustained release behaviour, which is favourable for the prevention and treatment of bone infections. The antibacterial assays against E. coli and S. aureus demonstrated that the composite scaffold with ROX possessed effective antibacterial activity, especially for S. aureus, the main cause of bone infection. The immunostaining and MTT assay with human osteoblast-like cells (MG63) indicated that cells showed good viability and growth on the scaffolds. Therefore, the melt EHD 3D printed PCL/PEG/ROX scaffold could be a promising anti-infective implant for bone tissue engineering.

Natural and edible materials have attracted increasing attention in food packaging, which could overcome the serious environmental issues caused by conventional non-biodegradable synthetic packaging. In this work, gelatin nanofibers incorporated with two kinds of essential oil (EO), peppermint essential oil (PO) and chamomile essential oil (CO), were fabricated by electrospinning for potential edible packaging application. Electron microscopy showed that smooth and uniform morphology of the gelatin/EOs was obtained, and the diameter of nanofibers was mostly enlarged with the increase of the EO content. The proton nuclear magnetic resonance spectrum confirmed the existence of PO and CO in nanofibers after electrospinning. The addition of EOs led to an enhancement of the water contact angle of nanofibers. The antioxidant activity was significantly improved for the nanofibers loaded with CO, while the antibacteria activity against Escherichia coli and Staphylococcus aureus was better for the fibers with PO addition. The combination of half PO and half CO in nanofibers compensated for their respective limitations and exhibited optimum bioactivities. Finally, the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay with NIH-3T3 fibroblasts demonstrated the absence of cytotoxicity of the gelatin/EO nanofibers. Thus, our studies suggest that the developed gelatin/PO/CO nanofiber could be a promising candidate for edible packaging.

Cell alignment is widely found in various tissues and organs in vivo, thus engineering of cell alignment is a significant issue in tissue engineering. Near-field melt electrospinning (NMES) is an emerging technique to produce polymer microfibers, which has been increasingly used to prepare scaffold; however, the effect of NMES micro-pattern on cell orientation guidance such as cell alignment has not been investigated systematically yet. In this study, poly(epsilon-caprolactone) (PCL) micro-line array was fabricated by NMES for cell alignment studies. Different from most previous reports, PCL micro-line array with improved fiber deposition accuracy and decreased fiber spacing (small to 10 mu m) was achieved by regulating the applied voltage and nozzle-to-collector distance. Cell alignment was observed on PCL micro-line arrays and the alignment effect weakened with the increase of the space between micro-lines. By MTT analysis, cells cultured on NMES PCL micro-line arrays showed better viability than that on plain substrate without PCL, which was advantageous over conventional electrospun nanofibers.

Honey is an ancient natural wound-healing agent and has been reintroduced to modern clinical wound care as it has various bioactivities. In this study, honey was incorporated into an alginate/PVA-based electrospun nanofibrous membrane to develop an efficient wound dressing material. The morphology and chemical composition of the nanofibrous membrane were observed by scanning electron microscopy and characterized via Fourier transform infrared spectroscopy, respectively, demonstrating that honey was successfully introduced to the nanofibers. The nanofibrous membranes with increasing honey content showed enhanced antioxidant activity, suggesting the ability to control the overproduction of reactive oxygen species. Disc diffusion assay and dynamic contact assay proved the antibacterial activity of the honey loaded nanofibers towards Gram-positive bacterium (Staphylococcus aureus) and Gram-negative bacterium (Escherichia coli). The cytotoxicity assay illustrated the non-cytotoxicity and biocompatibility of the nanofibrous membranes. Therefore, the developed honey/alginate/PVA nanofibrous membranes are promising for wound dressings.