Local delivery of methotrexate/glycyrrhizin-loaded hyaluronic acid nanofiber for the management of oral cancer

The challenges in treating oral cancer include the limited effectiveness and systemic side effects of conventional chemotherapy and radiation therapy. Hyaluronic acid (HA) based Glycyrrhizin (GL) and Methotrexate (MT) loaded localized delivery systems, specifically nanofiber (NF) based platforms, were developed to address these challenges. The electrospinning method was used for the successful fabrication of a homogenous NF membrane and characterized for morphology, drug entrapment efficiency, tensile strength, and ex-vivo mucoadhesive study. Also, it was evaluated for in-vitro drug release profile, ex-vivo drug permeability, in-vitro anti-inflammatory, apoptosis assay by MTT and flow, and against specific cell lines in order to determine their potential for therapeutic use. Superior tensile breaking force (50 g), mucoadhesive strength of 153 gm/cm2, drug permeability, and releasing properties of designed NF, making them perfect requirements for oral cavity delivery. The anticancer potential of MT in the MTT assay and flow cytometry analysis was significantly increased in oral epidermal carcinoma cell (KB cell) for drug-loaded NF with 63.97 ± 1.99 % apoptosis, at 24 h. With these incorporated, GL with MT in NF had an anti-inflammatory potential, also demonstrated in-vitro and in-vivo. In the Ehrlich Ascites Carcinoma (EAC) induced mice model, the optimal formulation's shows better potential for tumor regression when comparing the developed NF formulation to the drugs. Experimental results show that by lowering mucositis-related inflammation and enhancing the effectiveness of oral cancer treatment, a developed nanofiber-based local drug delivery system offers a feasible strategy for managing oral cancer.

Electrospinning Nonspinnable Sols to Ceramic Fibers and Springs

Electrospinning has been applied to produce ceramic fibers using sol gel-based spinning solutions consisting of ceramic precursors, a solvent, and a polymer to control the viscosity of the solution. However, the addition of polymers to the spinning solution makes the process more complex, increases the processing time, and results in porous mechanically weak ceramic fibers. Herein, we develop a coelectrospinning technique, where a nonspinnable sol (<10 mPa s) consisting of only the ceramic precursor(s) and solvent(s) is encapsulated inside a polymeric shell, forming core-shell precursor fibers that are further calcined into ceramic fibers with reduced porosity, decreased surface defects, uniform crystal packing, and controlled diameters. We demonstrate the versatility of this method by applying it to a series of nonspinnable sols and creating high-quality ceramic fibers containing TiO2, ZrO2, SiO2, and Al2O3. The polycrystalline TiO2 fibers possess excellent flexibility and a high Young's modulus reaching 54.3 MPa, solving the extreme brittleness problem of the previously reported TiO2 fibers. The single-component ZrO2 fibers exhibit a Young's modulus and toughness of 130.5 MPa and 11.9 KJ/m3, respectively, significantly superior to the counterparts prepared by conventional sol-gel electrospinning. We also report the creation of ceramic fibers in micro- and nanospring morphologies and examine the formation mechanisms using thermomechanical simulations. The fiber assemblies constructed by the helical fibers exhibit a density-normalized toughness of 3.5-5 times that of the straight fibers due to improved fracture strain. This work expands the selection of the electrospinning solution and enables the development of ceramic fibers with more attractive properties.

Unveiling the Mechanism of the in Situ Formation of 3D Fiber Macroassemblies with Controlled Properties

Electrospinning technique is well-known for the generation of different fibers. While it is a "simple" technique, it lies in the fact that the fibers are typically produced in the form of densely packed two-dimensional (2D) mats with limited thickness, shape, and porosity. The highly demanded three-dimensional (3D) fiber assemblies have been explored by time-consuming postprocessing and/or complex setup modifications. Here, we use a classic electrospinning setup to directly produce 3D fiber macrostructures only by modulating the spinning solution. Increasing solution conductivity modifies electrodynamic jet behavior and fiber assembling process; both are observed in situ using a high-speed camera. More viscous solutions render thicker fibers that own enhanced mechanical stiffness as examined by finite element analysis. We reveal the correlation between the universal solution parameters and the dimensionality of fiber assemblies, thereof, enlightening the design of more "3D spinnable" solutions that are compatible with any commercial electrospinning equipment. After a calcination step, ultralightweight ceramic fiber assemblies are generated. These inexpensive materials can clean up exceptionally large fractions of oil spillages and provide high-performance thermal insulation. This work would drive the development and scale-up production of next-generation 3D fiber materials for engineering, biomedical, and environmental applications.

The Use of Recycled PET for the Synthesis of New Mechanically Improved PVP Composite Nanofibers

Polyethylene terephthalate (PET) waste has become a major challenge for the conservation of the environment due to difficult degradation. For this reason, it is important to develop new recycling strategies for reusing this waste. In this work, the electrospinning technique was used to synthesize composite nanofibers of polyvinylpyrrolidone (PVP), recycling PET (RPET) that was obtained from the chemical recycling of postconsumer PET with glycolysis and styrene (ST) as a crosslinking agent. The polymer solutions were analyzed by viscosity and frequency sweeping, while the composite nanofibers were characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis/differential scanning calorimetry (TGA/DSC), and nanoindentation to compare their properties. The PVP nanofibers presented an average diameter of 257 nm; the RPET/PVP and RPET/PVP/ST composite nanofibers had average diameters of 361 nm and 394 nm, respectively; and the modulus of elasticity and hardness of the RPET/PVP/ST composite nanofibers were 29 and 20 times larger, respectively, than those of the PVP nanofibers. With the synthesis of these composite nanofibers, a new approach to PET recycling is presented.

Insights into Theranostic Properties of Titanium Dioxide for Nanomedicine

Titanium dioxide (TiO2) nanostructures exhibit a broad range of theranostic properties that make them attractive for biomedical applications. TiO2 nanostructures promise to improve current theranostic strategies by leveraging the enhanced quantum confinement, thermal conversion, specific surface area, and surface activity. This review highlights certain important aspects of fabrication strategies, which are employed to generate multifunctional TiO2 nanostructures, while outlining post-fabrication techniques with an emphasis on their suitability for nanomedicine. The biodistribution, toxicity, biocompatibility, cellular adhesion, and endocytosis of these nanostructures, when exposed to biological microenvironments, are examined in regard to their geometry, size, and surface chemistry. The final section focuses on recent biomedical applications of TiO2 nanostructures, specifically evaluating therapeutic delivery, photodynamic and sonodynamic therapy, bioimaging, biosensing, tissue regeneration, as well as chronic wound healing.

Development and characterization of rapid dissolving ornidazole loaded PVP electrospun fibers

Gingivitis is a common and mild form of periodontal disease and can be described as a limited inflammation of the gingiva. This study aims to develop and characterize rapid releasing mucoadhesive fibers containing ornidazole with electrospinning process for the treatment of gingivitis. Polyvinylpyrrolidone (PVP) was chosen as a polymer and used at different concentrations of 10%, 12.5%, and 15%. Scanning electron microscopy images showed that fiber diameters increased with increasing polymer concentrations. Tensile strength and elongation at break values of fibers increased with increasing PVP amount, whereas the loading of ornidazole into the fibers decreased these parameters. The contact angle values of all fibers were found to be 0° due to the hydrophilic nature of PVP. Ornidazole was released within 5 min and diffused from all of the fibers faster than that of gel and solution formulations. Electrospun ornidazole fibers were found efficient against Porphyromonas gingivalis in antimicrobial activity studies. The results demonstrated that ornidazole loaded fibers could be a potential drug delivery system for the treatment of gingivitis.