Fabrication and characterization of electrospun core-shell nanofibers of bilayer zein/pullulan emulsions crosslinked by genipin.

In this study, the electrospun core-shell nanofibers of zein/pullulan stabilized bilayer emulsions before and after genipin crosslinking were fabricated. The experimental results indicated that the addition of pullulan increased the apparent viscosity and elastic modulus of the bilayer emulsions, which was further increased after the chemical crosslinking of genipin. The nanofiber diameter increased from 102.9 nm to 169.9 nm with the increasing ratio of pullulan, but increased significantly to a range of 405.6-708.0 nm after genipin crosslinking. The electrospun nanofiber films of crosslinked emulsions had higher thermal stability and stronger water stability. The FTIR result proved the existence of hydrogen bond interaction between the zein, pullulan, and genipin molecules. In addition, before and after crosslinking, the encapsulation efficiency of electrospun fiber films for camellia oil was >77.68 %, and the maximum encapsulation efficiency could reach 87.94 %, and there was no significant change during the 7-day storage period, showing good stability. These research results can provide a theoretical basis for the encapsulation of hydrophobic active substances in zein-based emulsion electrospun core-shell nanofibers.

Reverse Gradient Distributions of Drug and Polymer Molecules within Electrospun Core-Shell Nanofibers for Sustained Release.

Core-shell nanostructures are powerful platforms for the development of novel nanoscale drug delivery systems with sustained drug release profiles. Coaxial electrospinning is facile and convenient for creating medicated core-shell nanostructures with elaborate designs with which the sustained-release behaviors of drug molecules can be intentionally adjusted. With resveratrol (RES) as a model for a poorly water-soluble drug and cellulose acetate (CA) and PVP as polymeric carriers, a brand-new electrospun core-shell nanostructure was fabricated in this study. The guest RES and the host CA molecules were designed to have a reverse gradient distribution within the core-shell nanostructures. Scanning electron microscope and transmission electron microscope evaluations verified that these nanofibers had linear morphologies, without beads or spindles, and an obvious core-shell double-chamber structure. The X-ray diffraction patterns and Fourier transform infrared spectroscopic results indicated that the involved components were highly compatible and presented in an amorphous molecular distribution state. In vitro dissolution tests verified that the new core-shell structures were able to prevent the initial burst release, extend the continuous-release time period, and reduce the negative tailing-off release effect, thus ensuring a better sustained-release profile than the traditional blended drug-loaded nanofibers. The mechanism underlying the influence of the new core-shell structure with an RES/CA reverse gradient distribution on the behaviors of RES release is proposed. Based on this proof-of-concept demonstration, a series of advanced functional nanomaterials can be similarly developed based on the gradient distributions of functional molecules within electrospun multi-chamber nanostructures.

Synergistic Effects of Radical Distributions of Soluble and Insoluble Polymers within Electrospun Nanofibers for an Extending Release of Ferulic Acid.

Polymeric composites for manipulating the sustained release of an encapsulated active ingredient are highly sought after for many practical applications; particularly, water-insoluble polymers and core-shell structures are frequently explored to manipulate the release behaviors of drug molecules over an extended time period. In this study, electrospun core-shell nanostructures were utilized to develop a brand-new strategy to tailor the spatial distributions of both an insoluble polymer (ethylcellulose, EC) and soluble polymer (polyvinylpyrrolidone, PVP) within the nanofibers, thereby manipulating the extended-release behaviors of the loaded active ingredient, ferulic acid (FA). Scanning electron microscopy and transmission electron microscopy assessments revealed that all the prepared nanofibers had a linear morphology without beads or spindles, and those from the coaxial processes had an obvious core-shell structure. X-ray diffraction and attenuated total reflectance Fourier transform infrared spectroscopic tests confirmed that FA had fine compatibility with EC and PVP, and presented in all the nanofibers in an amorphous state. In vitro dissolution tests indicated that the radical distributions of EC (decreasing from shell to core) and PVP (increasing from shell to core) were able to play their important role in manipulating the release behaviors of FA elaborately. On one hand, the core-shell nanofibers F3 had the advantages of homogeneous composite nanofibers F1 with a higher content of EC prepared from the shell solutions to inhibit the initial burst release and provide a longer time period of sustained release. On the other hand, F3 had the advantages of nanofibers F2 with a higher content of PVP prepared from the core solutions to inhibit the negative tailing-off release. The key element was the water permeation rates, controlled by the ratios of soluble and insoluble polymers. The new strategy based on core-shell structure paves a way for developing a wide variety of polymeric composites with heterogeneous distributions for realizing the desired functional performances.

Sodium alginate hydrogels co-encapsulated with cell free fat extract-loaded core-shell nanofibers and menstrual blood stem cells derived exosomes for acceleration of articular cartilage regeneration.

This study presents a novel scaffold system comprising sodium alginate hydrogels (SAh) co-encapsulated with cell-free fat extract (CEFFE)-loaded core-shell nanofibers (NFs) and menstrual blood stem cell-derived exosomes (EXOs). The scaffold integrates the regenerative potential of EXOs and CFFFE, offering a multifaceted strategy for promoting articular cartilage repair. Coaxially electrospun core-shell NFs exhibited successful encapsulation of CEFFE and seamless integration into the SAh matrix. Structural modifications induced by the incorporation of CEFFE-NFs enhanced hydrogel porosity, mechanical strength, and degradation kinetics, facilitating cell adhesion, proliferation, and tissue ingrowth. The release kinetics of growth factors from the composite scaffold demonstrated sustained and controlled release profiles, essential for optimal tissue regeneration. In vitro studies revealed high cell viability, enhanced chondrocyte proliferation, and migration in the presence of EXOs/CEFFE-NFs@SAh composite scaffolds. Additionally, in vivo experiments demonstrated significant cartilage regeneration, with the composite scaffold outperforming controls in promoting hyaline cartilage formation and defect bridging. Overall, this study underscores the potential of EXOs and CEFFE-NFs integrated into SAh matrices for enhancing chondrocyte viability, proliferation, migration, and ultimately, articular cartilage regeneration. Future research directions may focus on elucidating underlying mechanisms and conducting long-term in vivo studies to validate clinical applicability and scalability.

Core-shell electrospun polycaprolactone nanofibers, loaded with rifampicin and coated with silver nanoparticles, for tissue engineering applications.

In the field of tissue engineering, the use of core-shell fibers represents an advantageous approach to protect and finely tune the release of bioactive compounds with the aim to regulate their efficacy. In this work, core-shell electrospun polycaprolactone nanofiber-based membranes, loaded with rifampicin and coated with silver nanoparticles, were developed and characterized. The membranes are composed by randomly oriented nanofibers with a homogeneous diameter, as demonstrated by scanning electron microscopy (SEM). An air-plasma treatment was applied to increase the hydrophilicity of the membranes as confirmed by contact angle measurements. The rifampicin release from untreated and air-plasma treated membranes, evaluated by UV spectrophotometry, displayed a similar and constant over-time release profile, demonstrating that the air-plasma treatment does not degrade the rifampicin, loaded in the core region of the nanofibers. The presence and the distribution of silver nanoparticles on the nanofiber surface were investigated by SEM and Energy Dispersive Spectroscopy. Moreover, SEM imaging demonstrated that the produced membranes possess a good stability over time, in terms of structure maintenance. The developed membranes showed a good biocompatibility towards murine fibroblasts, human osteosarcoma cells and urotheliocytes, reveling the absence of cytotoxic effects. Moreover, doble-functionalized membranes inhibit the growth of E. coli and S. aureus. Thanks to the possibilities offered by the coaxial electrospinning, the membranes here proposed are promising for several tissue engineering applications.

Enhanced wound healing properties of biodegradable PCL/alginate core-shell nanofibers containing Salvia abrotanoides essential oil and ZnO nanoparticles.

Electrospun nanofibrous membranes, with their unique structural features, can potentially enhance wound healing through controlled delivery of active agents. Here, an innovative porous nanofibrous membrane was developed as a dressing patch with antibacterial and anti-inflammatory functionalities for cutaneous wound healing. Zinc oxide nanoparticles (ZnO NPs) and Salvia abrotanoides essential oil (SAEO) were incorporated into sodium alginate, which served as the shell. Poly(ε-caprolactone) was used as the core of coaxial electrospun wound dressing nanofibers (PCL/SA@ZnO/SAEO). With the addition of ZnO NPs and SAEO, the average diameter of nanofibers was 187 ± 51 nm, with improved tensile strength (4.7 ± 0.4 MPa), elongation at break (32.9 ± 2.1), and elastic modulus (21.4 ± 2.0). Concurrent application of ZnO NPs and SAEO increased antimicrobial activity against Staphylococcus aureus and Escherichia coli and promoted the proliferation, attachment, and viability (>90 %) of L929 cells. The PCL/SA@ZnO/SAEO scaffold accelerated the healing time with total wound healing over 14 days in mouse models carrying full-thickness wounds compared to the nanofibrous scaffold without additives. Histopathological examinations demonstrated better tissue regeneration, i.e., enhanced collagen deposition, improved re-epithelialization, and neovascularization, and increased quantity of hair follicles. Moreover, the chicken chorioallantoic membrane assay confirmed the synergistic angiogenic effects of SAEO and ZnO NPs. Finally, the in vitro and in vivo results proposed the bioactive core-shell nanofibers synthesized as encouraging wound dressing materials for hastening the healing of cutaneous wounds.

Mesoporous DNA-Co@C nanofibers knitted aptasensors performing onsite determination of trace kanamycin residues.

The abuse of kanamycin (KAN) poses an increasing threat to human health by contaminating agricultural and animal husbandry products, drinking water, and more. Therefore, the sensitive detection of trace KAN residues in real samples is crucial for monitoring agricultural pollution, ensuring food safety, and diagnosing diseases. However, traditional assay techniques for KAN rely on bulky instruments and complicated operations with unsatisfactory detection limits. Herein, we developed a novel label-free aptasensor to achieve ultrasensitive detection of KAN by constructing mesoporous DNA-cobalt@carbon nanofibers (DNA-Co@C-NFs) as the recognizer. Leveraging the extended π-conjugation structure, prominent surface area, and abundant pores, the Co@C-NFs can effectively load aptamer strands via π-π stacking interactions, serving as KAN capturer and reporter. Due to the change in DNA configuration upon binding KAN, this aptasensor presented an ultralow detection limit and ultra-wide linear range, along with favorable precision and selectivity. Using real tap water, milk, and human serum samples, the aptasensor accurately reported trace KAN levels. As a result, this convenient and rapid autosensing technique holds promise for onsite testing of other antibiotic residues in agriculture, food safety, and clinical diagnosis.

Heat-treated alginate-polycaprolactone core-shell nanofibers by emulsion electrospinning process for biomedical applications.

Fabrication of Core-shell nanofibrous mat which is a promising tool for a wide range of applications in tissue engineering can be developed using water in oil (W/O) or oil in water (O/W) emulsion electrospinning. In this study, for the first time, we fabricated an O/W emulsion-based electrospun core-shell mat using polycaprolactone (PCL) as a core and the blend solution of alginate (Alg) and polyethylene oxide (PEO) as shell material. To achieve a stable core-shell mat, firstly, Alg was modified with heat treatment to decrease the molecular weight of Alg. Then, to improve the chain flexibility of Alg, PEO as a second polymer was added to facilitate its electrospinnability. The different volume ratios of O/W were then fabricated by adding PCL to the Alg-PEO solution to find an optimized emulsion solution. The morphology, swelling, and porosity of the construct were evaluated. At the same time, the mechanical characteristic of fibers was evaluated in both dry and wet conditions. This study also examined cell-scaffold interactions to address the need for a scaffolding material to be suitable for tissue engineering and biomedical applications. Finally, the result exhibited a distinct core-shell structure with better mechanical properties compared to the Alg-PEO.

Investigation of antiproliferative efficacy and apoptosis induction in leukemia cancer cells using irinotecan-loaded liposome-embedded nanofibers constructed from chitosan.

Liposomes and nanofibers have been implemented as efficacious vehicles for delivering anticancer drugs. With this view, this study explores the antiproliferative efficacy and apoptosis induction in leukemia cancer cells utilizing irinotecan-loaded liposome-embedded nanofibers fabricated from chitosan, a biological source. Specifically, we investigate the effectiveness of poly(ε-caprolactone) (PCL)/chitosan (CS) (core)/irinotecan (CPT)nanofibers (termed PCL-CS10 CPT), PCL/chitosan/irinotecan (core)/PCL/chitosan (shell) nanofibers (termed CS/CPT/PCL/CS), and irinotecan-coloaded liposome-incorporated PCL/chitosan-chitosan nanofibers (termed CPT@Lipo/CS/PCL/CS) in releasing irinotecan in a controlled manner and treating leukemia cancer. The fabricated formulations were characterized utilizing Fourier transform infrared analysis, transmission electron microscopy, scanning electron microscopy, dynamic light scattering, zeta potential, and polydispersity index. Irinotecan was released in a controlled manner from nanofibers filled with liposomes over 30 days. The cell viability of the fabricated nanofibrous materials toward Human umbilical vein endothelial cells (HUVECs) non-cancerous cells after 168 h was >98 % ± 1 %. The CPT@Lipo/CS/PCL/CS nanofibers achieved maximal cytotoxicity of 85 % ± 2.5 % against K562 leukemia cancer cells. The CPT@Lipo/CS/PCL/CS NFs exhibit a three-stage drug release pattern and demonstrate significant in vitro cytotoxicity. These findings indicate the potential of these liposome-incorporated core-shell nanofibers for future cancer therapy.

Core-shell nanofibers based on microalgae proteins/alginate complexes for enhancing survivability of probiotics.

In this study, a novel one-step coaxial electrospinning process is employed to fabricate shell-core structure fibers choosing Chlorella pyrenoidosa proteins (CP) as the core material. These nanofibers, serving as the wall material for probiotic encapsulation, aimed to enhance the stability and antioxidant activity of probiotics in food processing, storage, and gastrointestinal environments under sensitive conditions. Morphological analysis was used to explore the beads-on-a-string morphology and core-shell structure of the electrospun fibers. Probiotics were successfully encapsulated within the fibers (7.97 log CFU/g), exhibiting a well-oriented structure along the distributed fibers. Compared to free probiotics and uniaxial fibers loaded with probiotics, encapsulation within microalgae proteins/alginate core-shell structure nanofibers significantly enhanced the probiotic cells' tolerance to simulated gastrointestinal conditions (p < 0.05). Thermal analysis indicated that microalgae proteins/alginate core-shell structure nanofibers displayed superior thermal stability compared to uniaxial fibers. The introduction of CP resulted in a 50 % increase in the antioxidant capacity of probiotics-loaded microalgae proteins/alginate nanofibers compared to uniaxial alginate nanofibers, with minimal loss of viability (0.8 log CFU/g) after 28 days of storage at 4 °C. In summary, this dual-layer carrier holds immense potential in probiotic encapsulation and enhancing their resistance to harsh conditions.

Multifunctional embelin- poly (3-hydroxybutyric acid) and sodium alginate-based core-shell electrospun nanofibrous mat for wound healing applications.

In this study, coaxial electrospinning is employed to make core-shell fibers, which represents a major advance in biomaterial innovation. Fibers that combine a protective shell and a therapeutic agent-loaded core, herald a revolutionary era in tissue engineering and wound care. Besides supporting cell growth, these fibers also preserve sterility, which makes them ideal for advanced wound dressings. We used embelin as the basis for this study because of its natural antibacterial properties. Its effectiveness in inhibiting the growth of bacteria made it the ideal candidate for our research. We have synthesized core-shell nanofibers that contain Sodium Alginate (SAL) in a Poly (ethylene oxide) (PEO) shell and Embelin in a Poly (3-hydroxybutyric acid) (PHB) core, which exhibit the homogeneity and flawless structure required for biomedical applications. When using SAL-PEO and EMB-PHB solutions dissolved in 1,1,1,3,3,3 hexafluoro-2-propanol (HFIP), high consistency in results can be achieved. A biocompatibility study was conducted using NIH-3T3 fibroblasts, which demonstrated remarkable adhesion and proliferation, with over 95 % growth supporting both PHB + SAL-PEO and EMB-PHB + SAL-PEO fibers. In addition, the scaffold loaded with Embelin shows strong antibacterial activity and cytocompatibility. The combined activity demonstrates the potential of EMB-PHB + SAL-PEO fibers in wound healing, where tissue regeneration and preservation of sterility are crucial. The optimized concentration of Embelin within these scaffolds demonstrates robust antibacterial efficacy while exhibiting minimal toxicity, thus positioning them as highly promising candidates for a wide range of biological applications, including wound healing.

Coaxial Electrospun Porous Core-Shell Nanofibrous Membranes for Photodegradation of Organic Dyes.

In this study, a series of AgCl/ZnO-loaded nanofibrous membranes were prepared using coaxial electrospinning. Their physical and chemical characteristics were evaluated by SEM, TEM, XRD, XPS, IR, PL, and UV-visible spectrometer, and the photocatalytic experiments using methylene blue (MB) as a model pollutant. The formation of AgCl/ZnO heterojunction and the structure of core-shell nanofibers with porous shell layer were confirmed. AgCl/ZnO photocatalysts were also effectively loaded onto the surfaces of the porous core-shell nanofibers. The results of photocatalytic experiments revealed that the AgCl/ZnO (MAgCl:MZnO = 5:5)-loaded nanofibrous membrane achieved a degradation efficiency of 98% in just 70 min and maintained a photocatalytic efficiency exceeding 95% over the first five experimental cycles, which successfully addressed the issues of photocatalytic efficiency loss during the photodegradation of MB with AgCl/ZnO nanoparticles as photocatalyst. The photodegradation mechanism was also researched and proposed.

Incorporation of doxorubicin and CoFe2O4 nanoparticles into the cellulose acetate phthalate / polyvinyl alcohol (core)/ polyurethane (shell) nanofibers against A549 human lung cancer during chemotherapy/hyperthermia combined method.

Cellulose acetate phthalate (CAP)/polyvinyl alcohol (PVA)/polyurethane (PU) nanofibers were synthesized by simple and coaxial electrospinning (ES) processes. Doxorubicin (DOX) and the CoFe2O4 nanoparticles were loaded into the nanofibers. The performance of the prepared nanofibers was investigated for the sustained release of DOX against A541 lung cancer cells under chemotherapy/external magnetic field (EMF) and alternating magnetic field (AMF, hyperthermia treatment) combined methods in both the in vitro and in vivo conditions. The sustained release of DOX from core-shell nanofibers containing 5 wt% cobalt ferrite was obtained within 300, 600 h, at pH of 5.5 and 7.4 without AMF and 168, 360 h, under an alternating magnetic field (AMF). More than 98.3 ± 0.2 % of A549 cancer cells were killed in the presence of core-shell nanofibers containing 100 µg DOX and 5 % cobalt ferrite nanoparticles in the presence of AMF. The flowcytometric results indicated that only 19.1 and 8.85 % cancer cells remained alive under EMF and AMF, respectively. The in vivo results revealed in stopping the growth of tumor volume and decrease in the relative tumor volume up to 0.5 were obtained using magnetic core-shell nanofibers containing 100 µg DOX and 5 % cobalt ferrite nanoparticles in the presence of EMF and AMF, respectively.

Polyacrylonitrile and polyethersulfone based co-axial electrospun nanofibers for fluoride removal from contaminated stream.

Coaxial electrospun polyacrylonitrile (PAN) and polyethersulfone (PES) based nanofibers were prepared and was used for filtration of fluoride from drinking water for the first time. Well defined fiber geometry was obtained at 1 ml/h of core polymer, i.e., PES flow rate, 1.4 ml/h of shell polymer, i.e., PAN flow rate, voltage of 22 kV, while the distance between the needle tip and the collector was 15-17 cm. Increase in bead like structure in fiber strands was observed with higher PAN concentration, while it decreased for lower PES concentration, thereby giving an optimum composition (6 wt% PAN and 10 wt% PES) for uniform fiber morphology. This nanofiber, abbreviated as N2 acted as an ultrafiltration membrane having permeability in the lower range, i.e., 0.5 × 10-11 m/s Pa and its fluoride removal efficacy was 46%. Fibers were also hydrophilic with considerable porous nature. Uptake of fluoride by this N2 nanofibers were evident from binding energy of 685.2 eV during XPS analysis. It is probable that nitrile and sulfone groups present in the core and shell of the nanofibers played an active in fluoride uptake, which was estimated as 110 mg/g at 298 K. Isoelectric point was in alkaline range which promoted negative fluoride ion uptake on positive nanofiber surface. Lead played higher masking effect in the uptake of fluoride in comparison to arsenic as coexisting ion. Dynamic cross flow filtration was also studied with this nanofiber in both synthetic and real life feed solution.

Airbrushed nanofibers with bioactive core and antibacterial shell for wound healing application.

Acute and chronic wounds are vulnerable to infection and delayed healing and require critical care and advanced wound protection. To overcome the challenges, dual therapy of antibacterial and growth factors will be a novel wound care strategy. The present study explores airbrushed core-shell nanofiber for dual delivery of epidermal growth factor (EGF) and amoxicillin (AMOX) in a sustained manner. A blend of polycaprolactone (PCL)-polyethylene oxide (PEO) was used to prepare the shell compartment for amoxicillin loading and poly-DL-lactide (PDLLA) core for EGF loading by using a customized airbrush setup. Characterization result shows a uniform distribution of nanofibers ranging between 200 and 500 nm in diameter. Amoxicillin loading in the shell compartment offers an initial burst release followed by a sustained release for up to 14 days. Whereas EGF in the core part shows a continuous sustained release throughout the release study.In-vitrostudy indicates the biocompatibility of EGF-AMOX loaded core-shell nanofibers with human dermal fibroblast cell (HDF) cells and a higher cellular proliferation compared to control samples. Gene expression data show an increase in fold change of collagen I and tropoelastin expression, indicating the regenerative properties of EGF-AMOX encapsulated nanofiber. The combination of bioactive core (EGF) and antibiotic shell (amoxicillin) in an airbrushed nanofibrous scaffold is a novel approach, which is the first time explored to deliver sustainable therapy to treat skin wounds. Our results demonstrate that PCL-PEO-Amoxicillin/PDLLA-EGF-loaded core-shell nanofibers are promising dual therapy scaffolds to deliver effective skin wound care, with the possibility of direct deposition on the wound.

Development of dual-functional core-shell electrospun mats with controlled release of anti-inflammatory and anti-bacterial agents for the treatment of corneal alkali burn injuries.

In this study, a novel dual-drug carrier for the co-administration of an anti-inflammatory and antibiotic agent consisting of core-shell nanofibers for the treatment of cornea alkali burns was designed. The core-shell nanofibers were prepared via coaxial electrospinning of curcumin-loaded silk fibroin as the core and vancomycin-loaded chitosan/polyvinyl alcohol (PVA) as the shell. Electron microscopy (SEM and TEM) images confirmed the preparation of smooth, bead-free, and continuous fibers that formed clear core-shell structures. For further studies, nanofiber mats were cross-linked by heat treatment to avoid rapid disintegration in water and improve both mechanical properties and drug release. The release profile of curcumin and vancomycin indicated an initial burst release, continued by the extended release of both drugs within 72 hours. Rabbit corneal cells demonstrated high rates of proliferation when evaluated using a cell metabolism assay. Finally, the therapeutic efficiency of core/shell nanofibers in healing cornea alkali burn was studied by microscopic and macroscopic observation, fluorescence staining, and hematoxylin-eosin assay on rabbit eyes. The anti-inflammatory activity of fabricated fibers was evaluated by enzyme-linked immunosorbent assay and Immunofluorescence analysis. In conclusion, using a robust array of in vitro and in vivo experiments this study demonstrated the ability of the dual-drug carriers to promote corneal re-epithelialization, minimize inflammation, and inhibit corneal neovascularization. Since these parameters are critical to the healing of corneal wounds from alkali burns, we suggest that this discovery represents a promising future therapeutic agent that warrants further study in humans.

Stable encapsulation of camellia oil in core-shell zein nanofibers fabricated by emulsion electrospinning.

This study aimed to develop core-shell nanofibers by emulsion electrospinning using zein-stabilized emulsions to encapsulate camellia oil effectively. The increasing oil volume fraction (φ from 10% to 60%) increased the apparent viscosity and average droplet size of emulsions, resulting in the average diameter of electrospun fibers increasing from 124.5 nm to 286.2 nm. The oil droplets as the core were randomly distributed in fibers in the form of beads, and the core-shell structure of fibers was observed in TEM images. FTIR indicated that hydrogen bond interactions occurred between zein and camellia oil molecules. The increasing oil volume fraction enhanced the thermal stability, hydrophobicity, and water stability of electrospun nanofiber films. The core-shell nanofibers with 10%, 20%, 40%, and 60% camellia oil showed encapsulation efficiency of 78.53%, 80.25%, 84.52%, and 84.39%, respectively, and had good storage stability. These findings contribute to developing zein-based core-shell electrospun fibers to encapsulate bioactive substances.

Fibrous dressing containing bioactive glass with combined chemotherapy and wound healing promotion for post-surgical treatment of melanoma.

Surgery is the mainstream treatment for melanoma. However, inappropriate post-surgical treatment could result in the tumor recurrence and sever tissue damage, which ultimately leads to the failure of therapy and significantly compromises the therapeutic outcome of surgery. Herein, taking advantages of the co-axial electrospinning technology, we construct a dual-function nanofibrous wound dressing for the post-surgical treatment of melanoma. Si-Ca-P-based mesoporous bioactive glass (MBG) was prepared by the template-sol-gel process, with the compositions being set as 60 SiO2: 36 CaO: 4 P2O5 in mol%. Through rational design, 5-fluorouracil (5-FU)-loaded MBG nanoparticles (MBG-U) are successfully incorporated into the fiber core with biodegradable poly(lactic-co-glycolic acid) (PLGA) as the cladding layer to form the core-shell nanofibers (MBG-U CSF), which achieves sustained releases of chemotherapeutic drug (i.e.,5-FU) and wound healing promotion function. Thereafter, the post-surgical melanoma model was established to evaluate the in-situ anti-cancer and wound healing effect of MBG-U CSF. Thereafter, the post-surgical melanoma model was established to evaluate the anti-cancer and wound healing effect. The results demonstrated that the core-shell nanofibrous dressing almost complete suppressed tumor growth, and simultaneously promoted skin regeneration, which provides a promising strategy for the post-surgical treatment for melanoma.

Paclitaxel-loaded liposome-incorporated chitosan (core)/poly(ε-caprolactone)/chitosan (shell) nanofibers for the treatment of breast cancer.

Liposomes and nanofibers have been introduced as effective drug delivery systems of anticancer drugs. The performance of chitosan (core)/poly(ε-caprolactone) (PCL)/paclitaxel simple nanofibers, chitosan/paclitaxel (core)/PCL/chitosan (shell) nanofibers and paclitaxel-loaded liposome-incorporated chitosan (core)/PCL-chitosan (shell) nanofibers was investigated for the controlled release of paclitaxel and the treatment of breast cancer. The synthesized formulations were characterized using polydispersity index, dynamic light scattering, zeta potential, scanning electron microscopy, transmission electron microscopy, and Fourier transform infrared analysis. The sustained release of paclitaxel from liposome-loaded nanofibers was achieved within 30 days. The release data was best described using Korsmeyer-Peppas pharmacokinetic model. The cell viabilities of synthesized nanofibrous samples were higher than 98 % ± 1 % toward L929 normal cells after 168 h. The maximum cytotoxicity against MCF-7 breast cancer cells was 85 % ± 2.5 % using liposome-loaded core-shell nanofibers. The in vivo results indicated the reduction of tumor weight from 1.35 ± 0.15 g to 0.65 ± 0.05 g using liposome-loaded core-shell nanofibers and its increasing from 1.35 ± 0.15 g to 3.2 ± 0.2 g using pure core-shell nanofibers. The three-stage drug release behavior of paclitaxel-loaded liposome-incorporated core-shell nanofibers and the high in vivo tumor efficiency suggested the development of these formulations for cancer treatment in the future.

Insights into electrospun pullulan-carboxymethyl chitosan/PEO core-shell nanofibers loaded with nanogels for food antibacterial packaging.

Nisin, a natural substance from Lactococcus lactis, displays a promising antibacterial ability against the gram-positive bacteria. However, it is susceptible to the external environment, i.e. temperature, pH, and food composition. In this study, a dual stabilization method, coaxial electrospinning, was applied to protect nisin in food packaging materials and the effect of nisin concentration on the properties of the nanofibers was investigated. The core-shell nanofibers with pullulan as a core layer and carboxymethyl chitosan (CMCS)/polyethylene oxide (PEO) as shell layer were prepared, and then the prepared CMCS-nisin nanogels (CNNGs) using a self-assembly method were loaded into the core layer of the nanofibers as antibacterial agents. The result revealed that the smooth surface can be observed on the nanofibers by microstructure characterization. The CNNGs-loaded nanofibers exhibited enhanced thermal stability and mechanical strength, as well as excellent antibacterial activity. Importantly, the as-formed nanofibers were applied to preserve bass fish and found that the shelf life of bass fish packed by CNNGSs with nisin at a concentration of 8 mg/mL was effectively extended from 9 days to 15 days. Taken together, the CNNGs can be well stabilized with the core-shell nanofibers, thus exerting significantly improved antimicrobial stability and bioactivity. This special structure exerts a great potential for application as food packaging materials to preserve aquatic products.