Fabrication and Characterization of Electrospun Folic Acid/Hybrid Fibers: In Vitro Controlled Release Study and Cytocompatibility Assays

Design and Application of Microfluidic Capture Device for Physical-Magnetic Isolation of MCF-7 Circulating Tumor Cells

Circulating tumor cells (CTCs) are a type of cancer cell that spreads from the main tumor to the bloodstream, and they are often the most important among the various entities that can be isolated from the blood. For the diagnosis of cancer, conventional biopsies are often invasive and unreliable, whereas a liquid biopsy, which isolates the affected item from blood or lymph fluid, is a less invasive and effective diagnostic technique. Microfluidic technologies offer a suitable channel for conducting liquid biopsies, and this technology is utilized to extract CTCs in a microfluidic chip by physical and bio-affinity-based techniques. This effort uses functionalized magnetic nanoparticles (MNPs) in a unique microfluidic chip to collect CTCs using a hybrid (physical and bio-affinity-based/guided magnetic) capturing approach with a high capture rate. Accordingly, folic acid-functionalized Fe3O4 nanoparticles have been used to capture MCF-7 (breast cancer) CTCs with capture efficiencies reaching up to 95% at a 10 µL/min flow rate. Moreover, studies have been conducted to support this claim, including simulation and biomimetic investigations.

Co-loading of Temozolomide with Oleuropein or rutin into polylactic acid core-shell nanofiber webs inhibit glioblastoma cell by controlled release

Glioblastoma (GB) has susceptibility to post-surgical recurrence. Therefore, local treatment methods are required against recurrent GB cells in the post-surgical area. In this study, we developed a nanofiber-based local therapy against GB cells using Oleuropein (OL), and rutin and their combinations with Temozolomide (TMZ). The polylactic acid (PLA) core-shell nanofiber webs were encapsulated with OL (PLAOL), rutin (PLArutin), and TMZ (PLATMZ) by an electrospinning process. A SEM visualized the morphology and the total immersion method determined the release characteristics of PLA webs. Real-time cell tracking analysis for cell growth, dual Acridine Orange/Propidium Iodide staining for cell viability, a scratch wound healing assay for migration capacity, and a sphere formation assay for tumor spheroid aggressiveness were used. All polymeric nanofiber webs had core-shell structures with an average diameter between 133 ± 30.7-139 ± 20.5 nm. All PLA webs promoted apoptotic cell death, suppressed cell migration, and spheres growth (p < 0.0001). PLAOL and PLATMZ suppressed GB cell viability with a controlled release that increased over 120 h, while PLArutin caused rapid cell inhibition (p < 0.0001). Collectively, our findings suggest that core-shell nano-webs could be a novel and effective therapeutic tool for the controlled release of OL and TMZ against recurrent GB cells.

Enhanced anti-tumor activity of transferrin/folate dual-targeting magnetic nanoparticles using chemo-thermo therapy on retinoblastoma cancer cells Y79

Malignant neoplasms are one of the main causes of death, especially in children, on a global scale, despite strenuous efforts made at advancing both diagnostic and therapeutic modalities. In this regard, a new nanocarrier Vincristine (VCR)-loaded Pluronic f127 polymer-coated magnetic nanoparticles conjugated with folic acid and transferrin (PMNP-VCR-FA-TF) were synthesized and characterized by various methods. The cytotoxicity of these nanoparticles was evaluated in vitro and ex vivo conditions. The in vitro anti-tumor effect of the nanoparticles was evaluated by colony formation assay (CFA) and reactive oxygen species (ROS) in Y79 cell line. The results showed that nanoparticles with two ligands conferred greater toxicity toward Y79 cancer cells than ARPE19 normal cells. Under an alternating magnetic field (AMF), these nanoparticles demonstrated a high specific absorption rate. The CFA and ROS results indicated that the AMF in combination with PMNP-VCR-FA-TF conferred the highest cytotoxicity toward Y79 cells compared with other groups (P < 0.05). PMNP-VCR-FA-TF could play an important role in converting externally applied radiofrequency energy into heat in cancer cells. The present study confirmed that dual targeting chemo-hyperthermia using PMNP-VCR-FA-TF was significantly more effective than hyperthermia or chemotherapy alone, providing a promising platform for precision drug delivery as an essential component in the chemotherapy of retinoblastoma.

Electrospun composite nanofibers of deoxyribonucleic acid and polylactic acid for skincare applications

The development of useful biomaterials has resulted in significant advances in various fields of science and technology. The demand for new biomaterial designs and manufacturing techniques continues to grow, with the goal of building a sustainable society. In this study, two types of DNA-cationic surfactant complexes were synthesized using commercially available deoxyribonucleic acid from herring sperm DNA (hsDNA, <50 bp) and deoxyribonucleic acid from salmon testes DNA (stDNA, ~2000 bp). The DNA-surfactant complexes were blended with a polylactic acid (PLA) biopolymer and electrospun to obtain nanofibers, and then copper nanoparticles were synthesized on nanofibrous webs. Scanning electron microscopic images showed that all nanofibers possessed uniform morphology. Interestingly, different diameters were observed depending on the base pairs in the DNA complex. Transmission electron microscopy showed uniform growth of copper nanoparticles on the nanofibers. Fourier-transform infrared spectroscopy spectra confirmed the uniform blending of both types of DNA complexes in PLA. Both stDNA- and hsDNA-derived nanofibers showed greater biocompatibility than native PLA nanofibers. Furthermore, they exerted significant antibacterial activity in the presence of copper nanoparticles. This study demonstrates that DNA is a potentially useful material to generate electrospun nanofibrous webs for use in biomedical sciences and technologies.

Lupeol-loaded chitosan-Ag+ nanoparticle/sericin hydrogel accelerates wound healing and effectively inhibits bacterial infection

Lupeol, a pentacyclic triterpene, has demonstrated significant wound healing properties; however, its low water solubility has limited its clinical applicability. To overcome this limitation, we utilized Ag⁺-modified chitosan (CS-Ag) nanoparticles to deliver lupeol, resulting in the formation of CS-Ag-L-NPs. These nanoparticles were then encapsulated within a temperature-sensitive, self-assembled sericin hydrogel. Various analytical methods, including SEM, FTIR, XRD, HPLC, TGA assay, hemolysis and antibacterial activity tests, were employed to characterize the nanoparticles. Additionally, an infectious wound model was used to evaluate the therapeutic and antibacterial efficacy of the CS-Ag-L-NPs modified sericin hydrogel. Our results showed that the encapsulation efficiency of lupeol in CS-Ag-L-NPs reached 62.1 %, with good antibacterial activity against both gram-positive and gram-negative bacteria and a low hemolysis ratio (<5 %). The CS-Ag-L-NPs sericin gel exhibited multiple beneficial effects, including inhibiting bacterial proliferation in wound beds, promoting wound healing via accelerated re-epithelialization, reducing inflammation, and enhancing collagen fiber deposition. We conclude that the CS-Ag-L-NPs loaded sericin hydrogel has tremendous potential for development as a multifunctional therapeutic platform capable of accelerating wound healing and effectively suppressing bacterial infections in clinical settings.

Self-Healing of Biocompatible Superhydrophobic Coatings: The Interplay of the Size and Loading of Particles

The broad application potential of superhydrophobic coatings is limited by the usage of environment-threatening materials and poor durability. The nature-inspired design and fabrication of self-healing coatings is a promising approach for addressing these issues. In this study, we report a fluorine-free and biocompatible superhydrophobic coating that can be thermally healed after abrasion. The coating is composed of silica nanoparticles and carnauba wax, and the self-healing is based on surface enrichment of wax in analogy to the wax secretion in plant leaves. The coating not only exhibits fast self-healing, just in 1 min under moderate heating, but also displays increased water repellency and thermal stability after healing. The rapid self-healing ability of the coating is attributed to the relatively low melting point of carnauba wax and its migration to the surface of the hydrophilic silica nanoparticles. The dependence of self-healing on the size and loading of particles provides insights into the process. Furthermore, the coating exhibits high levels of biocompatibility where the viability of fibroblast L929 cells was ∼90%. The presented approach and insights provide valuable guidelines in the design and fabrication of self-healing superhydrophobic coatings.

A novel transdermal delivery route for energy supplements: Electrospun chitosan/polyvinyl alcohol nanofiber patches loaded with vitamin B12

Nanofibrous patches have attracted much attention as a solution to resolve drug delivery challenges. In this study, vitamin B₁₂- loaded polyvinyl alcohol (PVA)/chitosan (Cs) nanofiber patch (NFP) was electrospun and cross-linked by glutaraldehyde (GA). The physicochemical properties of the nanofiber patches were assessed by morphological studies, FTIR analysis, hydrophilicity test, mechanical tests, and in-vitro evaluations including biodegradability, MTT assay, and cumulative release test of vitamin. In-vivo studies were also carried out by measuring vitamin B₁₂ levels in the bloodstream and conducting histopathology studies on the animal models. The results showed that the mean diameter of Cs/PVA/B₁₂ and cross-linked patch were approximately 207 and 256 nm, respectively. Cross-linking of NFP led to the lower, slower, and more continuous release of the vitamin with a slight decrease in biodegradability, and an increase in the mechanical properties of the nanofiber patches. Furthermore, the cytocompatibility assay, MTT, and in vivo results revealed no cytotoxicity of Cs/PVA/B₁₂ NFP towards L929 cell line. No lesion or tissue damage was observed in the skin tissue of the animal models wearing these skin patches. Therefore, B₁₂-loaded NFP can be introduced as a potential candidate for commercial transdermal routes.

Electrospinning of Microstructures Incorporated with Vitamin B9 for Food Application: Characteristics and Bioactivities

The food industry has been expanding, and new vectors to entrap vitamins have been constantly investigated, aiming at versatile systems with good physico-chemical characteristics, low-cost production, high stability and the efficient release of active ingredients. The vitamin B9 (folic acid or folate) is essential for the healthy functioning of a variety of physiological processes in humans and is beneficial in preventing a range of disorders. In this study, two approaches were developed to encapsulate vitamin B9. Zein and the combination of modified starch with two plasticizers were the selected encapsulating agents to produce microstructures via the electrospinning technique. The objective was to improve the stability and the B9 antioxidant capacity in the final formulations. The work strategy was to avoid limitations such as low bioavailability, stability and thermosensitivity. The microstructures were fabricated and the morphology and shape were assessed by scanning electron microscopy. The B9 release profiles of modified starch and zein microstructures were analyzed in simulated gastric fluid at 37 °C, and in deionized water and ethanol at room temperature. The B9 encapsulation efficiency and the stability of the systems were also studied. The ABTS assay was assessed and the antioxidant activity of the produced microstructures was evaluated. The physico-chemical characterization of loaded B9 in the microstructures was achieved. High encapsulation efficiency values were achieved for the 1% B9 loaded in 12% w/w modified starch film; 5% B9 vitamin encapsulated by the 15% w/w modified starch with 4% w/w tween 80; and 4% w/w glycerol film with heterogeneous microstructures, 5% w/w zein compact film and 10% w/w zein film. In conclusion, the combinations of 7 wt.% of modified starch with 4 wt.% tween 80 and 4 wt.% glycerol; 15 wt.% of modified starch with 4 wt.% tween 80 and 4 wt.% glycerol; and 12 wt.% modified starch and 5 wt.% zein can be used as delivery structures in order to enhance the vitamin B9 antioxidant activity in the food and nutraceutical fields.

Preparation of surface-functionalized electrospun PVA nanowebs for potential remedy for SARS-CoV-2

Infections with coronaviruses remain a burden that is negatively affecting human life. The use of metal oxides to prevent and control the spread of severe acute respiratory syndrome coronavirus (SARS-CoV-2) has been widely studied. However, the use of metal oxides in masks to enhance the performances of barrier face coverings in trapping and neutralizing SARS-CoV-2 remained unexplored. In the present study, we explore the possibility of developing surface functional PVA/ZnO electrospun nanowebs to be used as a component of multilayer barrier face coverings. Polyvinyl alcohol (PVA) and zinc acetate (ZnA) nanowebs were electrospun as precursor samples. After calcination at 400 degrees centigrade under a controlled atmosphere of nitrogen gas, product nanowebs containing ZnO (PVA/ZnO) were obtained. The presence of ZnO was determined using an attenuated total reflectance Fourier Transform Infrared (FT-IR) spectrometer. This study inspired the possibility of developing surface-functional materials to produce enhanced performance masks against the spread of SARS-CoV-2.

Electrospun Core–Sheath Nanofibers with Variable Shell Thickness for Modifying Curcumin Release to Achieve a Better Antibacterial Performance

The inefficient use of water-insoluble drugs is a major challenge in drug delivery systems. Core–sheath fibers with various shell thicknesses based on cellulose acetate (CA) were prepared by the modified triaxial electrospinning for the controlled and sustained release of the water-insoluble Chinese herbal active ingredient curcumin. The superficial morphology and internal structure of core–sheath fibers were optimized by increasing the flow rate of the middle working fluid. Although the prepared fibers were hydrophobic initially, the core–sheath structure endowed fibers with better water retention property than monolithic fibers. Core–sheath fibers had flatter sustained-release profiles than monolithic fibers, especially for thick shell layers, which had almost zero-order release for almost 60 h. The shell thickness and sustained release of drugs brought about a good antibacterial effect to materials. The control of flow rate during fiber preparation is directly related to the shell thickness of core–sheath fibers, and the shell thickness directly affects the controlled release of drugs. The fiber preparation strategy for the precise control of core–sheath structure in this work has remarkable potential for modifying water-insoluble drug release and improving its antibacterial performance.

Electrospun Composite Nanofibers for Functional Applications

Summary of the Special Issue: [...]

Elaborate design of shell component for manipulating the sustained release behavior from core–shell nanofibres

Background

The diversified combination of nanostructure and material has received considerable attention from researchers to exploit advanced functional materials. In drug delivery systems, the hydrophilicity and sustained–release drug properties are in opposition. Thus, difficulties remain in the simultaneous improve sustained–release drug properties and increase the hydrophilicity of materials.

Methods

In this work, we proposed a modified triaxial electrospinning strategy to fabricate functional core–shell fibres, which could elaborate design of shell component for manipulating the sustained-release drug. Cellulose acetate (CA) was designed as the main polymeric matrix, whereas polyethylene glycol (PEG) was added as a hydrophilic material in the middle layer. Cur, as a model drug, was stored in the inner layer.

Results

Scanning electron microscopy (SEM) results and transmission electron microscopy (TEM) demonstrated that the cylindrical F2–F4 fibres had a clear core–shell structure. The model drug Cur in fibres was verified in an amorphous form during the X-ray diffraction (XRD) patterns, and Fourier transformed infrared spectroscopy (FTIR) results indicated good compatibility with the CA matrix. The water contact angle test showed that functional F2–F4 fibres had a high hydrophilic property in 120 s and the control sample F1 needed over 0.5 h to obtain hydrophilic property. In the initial stage of moisture intrusion into fibres, the quickly dissolved PEG component guided the water molecules and rapidly eroded the internal structure of functional fibres. The good hydrophilicity of F2–F4 fibres brought relatively excellent swelling rate around 4600%. Blank outer layer of functional F2 fibres with 1% PEG created an exciting opportunity for providing a 96 h sustained-release drug profile, while F3 and F4 fibres with over 3% PEG provided a 12 h modified drug release profile to eliminate tailing–off effect.

Conclusion

Here, the functional F2–F4 fibres had been successfully produced by using the advanced modified triaxial electrospinning nanotechnology with different polymer matrices. The simple strategy in this work has remarkable potential to manipulate hydrophilicity and sustained release of drug carriers, meantime it can also enrich the preparation approaches of functional nanomaterials.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s12951-022-01463-0.