Vitamin D3-loaded electrospun cellulose acetate/polycaprolactone nanofibers: Characterization, in-vitro drug release and cytotoxicity studies

Biomimicking trilayer scaffolds with controlled estradiol release for uterine tissue regeneration

Scaffold-based tissue engineering provides an efficient approach for repairing uterine tissue defects and restoring fertility. In the current study, a novel trilayer tissue engineering scaffold with high similarity to the uterine tissue in structure was designed and fabricated via 4D printing, electrospinning and 3D bioprinting for uterine regeneration. Highly stretchable poly(l-lactide-co-trimethylene carbonate) (PLLA-co-TMC, "PTMC" in short)/thermoplastic polyurethane (TPU) polymer blend scaffolds were firstly made via 4D printing. To improve the biocompatibility, porous poly(lactic acid-co-glycolic acid) (PLGA)/gelatin methacryloyl (GelMA) fibers incorporated with polydopamine (PDA) particles were produced on PTMC/TPU scaffolds via electrospinning. Importantly, estradiol (E2) was encapsulated in PDA particles. The bilayer scaffolds thus produced could provide controlled and sustained release of E2. Subsequently, bone marrow derived mesenchymal stem cells (BMSCs) were mixed with gelatin methacryloyl (GelMA)-based inks and the formulated bioinks were used to fabricate a cell-laden hydrogel layer on the bilayer scaffolds via 3D bioprinting, forming ultimately biomimicking trilayer scaffolds for uterine tissue regeneration. The trilayer tissue engineering scaffolds thus formed exhibited a shape morphing ability by transforming from the planar shape to tubular structures when immersed in the culture medium at 37°C. The trilayer tissue engineering scaffolds under development would provide new insights for uterine tissue regeneration.

Fabrication and Characterization of Electrospun Ocimum sanctum and Curcumin-Loaded Nanofiber Membrane for the Management of Periodontal Disease: An In Vitro Study

Background Periodontal disease is a chronic inflammatory condition that gradually deteriorates the supportive tissues of teeth, eventually leading to tooth loss. Mechanical debridement stands as the gold standard method for treating periodontitis. However, antimicrobial therapy is recommended for optimal results when used alongside mechanical debridement. Numerous studies have investigated local drug delivery as an adjunct to mechanical debridement of affected tooth surfaces. Ocimum sanctum exhibits anti-inflammatory, antioxidant, and antimicrobial properties. Similarly, curcumin, as documented in the literature, demonstrates a broad spectrum of anti-inflammatory and antimicrobial effects. Electrospinning has demonstrated itself to be a highly effective method for fabricating drug-loaded fibers. Electrospun nanofibers containing Ocimum sanctum and curcumin are expected to exhibit greater efficacy due to their increased surface area, facilitating the dispersion of larger quantities of drugs, and their ability to control drug release when employed as a local drug delivery system. This study aims to fabricate and characterize the properties of nanofiber membranes loaded with Ocimum sanctum and curcumin using the electrospinning technique. Methods About 50 mg each of Ocimum sanctum and curcumin were blended with 15% polyvinyl alcohol and 2% chitosan polymer in a 4:1 ratio and left to stir overnight. A 10 mL syringe was filled with this solution, and an 18 G blunt-end needle charged at 15.9 kV was used for extrusion. Continuous fibers were collected onto a collector plate positioned 12 cm from the center of the needle tip, at a flow rate of 0.005 mL/min. The morphology of the fabricated membrane was assessed through scanning electron microscopy (SEM), the strength of the material was assessed through tensile strength analysis using INSTRON, an Electropuls E3000 Universal Testing Machine (INSTRON, Norwood, MA), and the drug release pattern was analyzed using Jasco V-730 UV-visible spectrophotometer (Jasco, Easton, MD). Results The morphology of this nanofiber showed a random distribution of fibers with no bead formation. The average diameter of the membrane was 383±102 nm, and the tensile strength of this material was 1.87 MPa. The drug release pattern showed an initial burst release of Ocimum sanctum, followed by a controlled release in subsequent hours. However, curcumin showed very little drug release because of its solubility. Conclusion In summary, the Ocimum sanctum and curcumin-loaded nanofibers exhibited robust tensile strength, a controlled drug release profile, and uniform drug distribution within the nanofiber membrane. Consequently, it can be concluded that curcumin nanofibers and electrospun Ocimum sanctum serve as valuable agents for local drug delivery in the treatment of periodontitis.

Fabrication and evaluation of a bi-layered electrospun PCL/PVA patch for wound healing: Release of vitamins and silver nanoparticle

There is still little research on the co-delivery of vitamins and AgNPs to accelerate wound healing. In this study, a bi-layered electrospun PCL/PVA patch loaded with Vitamin C, Vitamin B12, and AgNPs was fabricated using a co-spinning technique. SEM, FTIR, degradation, swelling, tensile strength, disk diffusion, and MTT assay were studied. Nine rats were placed in three groups (control: no treatment, G1: without agents, and G2: with agents) for 14 days in an in-vivo study. H&E and Masson Trichrome staining were employed for histological analysis. Results showed that the final electrospun wound dressings depicted nanofibers with diameters ranging from 100 to 500 nm. The presence of AgNP enhanced the mechanical strength (40-50 MPs). An appropriate swelling (100 %) and degradation (50 %) rate was observed for groups with no significant difference (P > 0.05). G1 and G2 did not show a significant difference in terms of porosity (65 % vs. 69 %). Regarding WVTR, G2 demonstrated higher WVTR (88 vs. 95 g/m2. h). G2 showed a vitamin release of more than 90 % after 48 h. Compared to G1, G2 demonstrated good antibacterial activity (>3 cm) against E. Coli and S. aureous (P < 0.01), with cell viability of more than 93 % (P > 0.05). Furthermore, the in-vivo study approved that G2 accelerated wound healing in full-thickness wounds, compared to the control groups, with notable wound size reduction (8 mm), epithelialization, and collagen formation. The findings support the use of this simple but potent electrospun wound dressing for the healing of full-thickness wounds.

Gelatin-nanocellulose stabilized emulsion-filled hydrogel beads loaded with curcumin: Preparation, encapsulation and release behavior

In this study, the curcumin was firstly encapsulated in gelatin (GLT) and/or cellulose nanocrystals (CNC) stabilized emulsions, then further mixed with sodium alginate (SA) to form emulsion-filled hydrogel beads loaded with curcumin (Cur). The Cur-loaded emulsions showed a droplet size of 20.3-24.4 μm with a uniform distribution. Introducing CNC and/or SA increased the viscosity of emulsions accompanied by viscoelastic transition, while the modulus was reduced due to destruction of GLT gel. Cur was doubly immobilized in the hydrogel beads with >90 % of encapsulation efficiency. The results of simulated gastrointestinal tract experiments revealed that the beads possessed a good pH sensitivity and controlled release behavior to prolong the retention of Cur in the gastrointestinal tract. After 6 h of UV irradiation, the Cur-loaded emulsion-filled hydrogel beads showed a higher antioxidant activity than that of pure Cur, effectively delaying the photodegradation of Cur. In addition, the beads had better stability in aqueous and acidic environments, which was favorable for prolonging the release of Cur. These results suggest that the emulsion-filled hydrogel beads have great potential for the delivery of lipophilic bioactive molecules.

Emerging trends and challenges in polysaccharide derived materials for wound care applications: A review

Polysaccharides are favourable and promising biopolymers for wound care applications due to their abundant natural availability, low cost and excellent biocompatibility. They possess different functional groups, such as carboxylic, hydroxyl and amino, and can easily be modified to obtain the desirable properties and various forms. This review systematically analyses the recent progress in polysaccharides derived materials for wound care applications, emphasizing the most commonly used cellulose, chitosan, alginate, starch, dextran and hyaluronic acid derived materials. The distinctive attributes of each polysaccharide derived wound care material are discussed in detail, along with their different forms, i.e., films, membranes, sponges, nanoemulsions, nanofibers, scaffolds, nanocomposites and hydrogels. The processing methods to develop polysaccharides derived wound care materials are also summarized. In the end, challenges related to polysaccharides derived materials in wound care management are listed, and suggestions are given to expand their utilization in the future to compete with conventional wound healing materials.

Nanofibers of N,N,N-trimethyl chitosan capped bimetallic nanoparticles: Preparation, characterization, wound dressing and in vivo treatment of MDR microbial infection and tracking by optical and photoacoustic imaging

Recent advancements in wound care have led to the development of interactive wound dressings utilizing nanotechnology, aimed at enhancing healing and combating bacterial infections while adhering to established protocols. Our novel wound dressings consist of N,N,N-trimethyl chitosan capped gold‑silver nanoparticles (Au-Ag-TMC-NPs), with a mean size of 108.3 ± 8.4 nm and a zeta potential of +54.4 ± 1.8 mV. These optimized nanoparticles exhibit potent antibacterial and antifungal properties, with minimum inhibitory concentrations ranging from 0.390 μg ml-1 to 3.125 μg ml-1 and also exhibited promising zones of inhibition against multi-drug resistant strains of S. aureus, E. coli, P. aeruginosa, and C. albicans. Microbial transmission electron microscopy reveals substantial damage to cell walls and DNA condensation post-treatment. Furthermore, the nanoparticles demonstrate remarkable inhibition of microbial efflux pumps and are non-hemolytic in human blood. Incorporated into polyvinyl alcohol/chitosan nanofibers, they form Au-Ag-TMC-NPs-NFs with diameters of 100-350 nm, facilitating efficient antimicrobial wound dressing. In vivo studies on MDR microbial-infected wounds in mice showed 99.34 % wound healing rate within 12 days, corroborated by analyses of wound marker protein expression levels and advanced imaging techniques such as ultrasound/photoacoustic imaging, providing real-time visualization and blood flow assessment for a comprehensive understanding of the dynamic wound healing processes.

Electrospun multi-chamber core-shell nanofibers and their controlled release behaviors: A review

Core-shell structure is a concentric circle structure found in nature. The rapid development of electrospinning technology provides more approaches for the production of core-shell nanofibers. The nanoscale effects and expansive specific surface area of core-shell nanofibers can facilitate the dissolution of drugs. By employing ingenious structural designs and judicious polymer selection, specialized nanofiber drug delivery systems can be prepared to achieve controlled drug release. The synergistic combination of core-shell structure and materials exhibits a strong strategy for enhancing the drug utilization efficiency and customizing the release profile of drugs. Consequently, multi-chamber core-shell nanofibers hold great promise for highly efficient disease treatment. However, little attention concentration is focused on the effect of multi-chamber core-shell nanofibers on controlled release of drugs. In this review, we introduced different fabrication techniques for multi-chamber core-shell nanostructures, including advanced electrospinning technologies and surface functionalization. Subsequently, we reviewed the different controlled drug release behaviors of multi-chamber core-shell nanofibers and their potential needs for disease treatment. The comprehensive elucidation of controlled release behaviors based on electrospun multi-chamber core-shell nanostructures could inspire the exploration of novel controlled delivery systems. Furthermore, once these fibers with customizable drug release profiles move toward industrial mass production, they will potentially promote the development of pharmacy and the treatment of various diseases. This article is categorized under: Therapeutic Approaches and Drug Discovery > Emerging Technologies.

Vitamin D3-incorporated chitosan/collagen/fibrinogen scaffolds promote angiogenesis and endothelial transition via HIF-1/IGF-1/VEGF pathways in dental pulp stem cells

Effective vascularization during wound healing remains a critical challenge in the regeneration of skin tissue. On the other hand, mesenchymal stem cell (MSC) to endothelial phenotype transition (MEnDoT) is a potential phenomenon grossly underexplored in vascularized skin tissue engineering. Vitamin D3 has a proven role in promoting MEnDoT. Hence, a D3-incorporated scaffold made with biocompatible materials such as chitosan, collagen and fibrinogen should be able to promote endothelial lineage transition in vitro for tissue engineering purposes. In this study, we developed vitamin D3 incorporated chitosan-collagen-fibrinogen (CCF-D3) scaffolds physically crosslinked under UV and conducted thorough physicochemical and biological assays on it compared to a control scaffold without vitamin D3. Our study for the first time reports the potential vascularization property of the CCF-D3 scaffold by inducing the transitions of dental pulp MSC to endothelial lineage via the HIF-1/IGF-1/VEGF pathways. MSC seeded on UV-exposed CCF-D3 scaffolds had higher cell viability and transitioned towards endothelial lineage was observed by elevated proliferative and endothelial-specific gene expressions and flow cytometric analysis of SCA-1+ antibody. The difference in VEGF-A and α-SMA expressions was also observed in the D3-CCF scaffold compared to the scaffolds without D3.

Drug cross-linking electrospun fiber for effective infected wound healing

The management of infected wounds is still an intractable challenge in clinic. Development of antibacterial wound dressing is of great practical significance for wound management. Herein, a natural-derived antibacterial drug, tannic acid (TA), was incorporated into the electrospun polyvinyl alcohol (PVA) fiber (TA/PVA fiber, 952 ± 40 nm in diameter). TA worked as a cross-linker via hydrogen bonding with PVA to improve the physicochemical properties of the fiber and to reach a sustained drug release (88% release of drug at 48 h). Improved mechanical property (0.8-1.2 MPa) and computational simulation validated the formation of the hydrogen bonds between TA and PVA. Moreover, the antibacterial and anti-inflammatory characteristics of TA laid the foundation for the application of TA/PVA fiber in repairing infected wounds. Meanwhile, in vitro studies proved the high hemocompatibility and cytocompatibility of TA/PVA fiber. Further in vivo animal investigation showed that the TA/PVA fiber promoted the repair of infected wound by inhibiting the bacterial growth, promoting granulation formation, and collagen matrix deposition, accelerating angiogenesis, and inducing M2 macrophage polarization within 14 days. All the data demonstrated that the TA cross-linked fiber would be a potent dressing for bacteria-infected wound healing.

Vitamin C fortification: need and recent trends in encapsulation technologies

The multifaceted role of vitamin C in human health intrudes several biochemical functions that are but not limited to antioxidant activity, homoeostasis, amino acid synthesis, collagen synthesis, osteogenesis, neurotransmitter production and several yet to be explored functions. In absence of an innate biosynthetic pathway, humans are obligated to attain vitamin C from dietary sources to maintain its optimal serum level (28 μmol/L). However, a significant amount of naturally occurring vitamin C may deteriorate due to food processing, storage and distribution before reaching to the human gastrointestinal tract, thus limiting or mitigating its disease combating activity. Literature acknowledges the growing prevalence of vitamin C deficiency across the globe irrespective of geographic, economic and population variations. Several tools have been tested to address vitamin C deficiency, which are primarily diet diversification, biofortification, supplementation and food fortification. These strategies inherit their own advantages and limitations. Opportunely, nanotechnology promises an array of delivery systems providing encapsulation, protection and delivery of susceptible compounds against environmental factors. Lack of clear understanding of the suitability of the delivery system for vitamin C encapsulation and fortification; growing prevalence of its deficiency, it is a need of the hour to develop and design vitamin C fortified food ensuring homogeneous distribution, improved stability and enhanced bioavailability. This article is intended to review the importance of vitamin C in human health, its recommended daily allowance, its dietary sources, factors donating to its stability and degradation. The emphasis also given to review the strategies adopted to address vitamin c deficiency, delivery systems adopted for vitamin C encapsulation and fortification.

Osteoinductive Electrospun Scaffold Based on PCL-Col as a Regenerative Therapy for Peri-Implantitis

Peri-implantitis is a serious condition affecting dental implants that can lead to implant failure and loss of osteointegration if is not diagnosed and treated promptly. Therefore, the development of new materials and approaches to treat this condition is of great interest. In this study, we aimed to develop an electrospun scaffold composed of polycaprolactone (PCL) microfibers loaded with cholecalciferol (Col), which has been shown to promote bone tissue regeneration. The physical and chemical properties of the scaffold were characterized, and its ability to support the attachment and proliferation of MG-63 osteoblast-like cells was evaluated. Our results showed that the electrospun PCL-Col scaffold had a highly porous structure and good mechanical properties. The resulting scaffolds had an average fiber diameter of 2-9 μm and high elongation at break (near six-fold under dry conditions) and elasticity (Young modulus between 0.9 and 9 MPa under dry conditions). Furthermore, the Col-loaded scaffold was found to decrease cell proliferation when the Col content in the scaffolds increased. However, cytotoxicity analysis proved that the PCL scaffold on its own releases more lactate dehydrogenase into the medium than the scaffold containing Col at lower concentrations (PCL-Col A, PCL-Col B, and PCL-Col C). Additionally, the Col-loaded scaffold was shown to effectively promote the expression of alkaline phosphatase and additionally increase the calcium fixation in MG-63 cells. Our findings suggest that the electrospun membrane loaded with Col can potentially treat peri-implantitis by promoting bone formation. However, further studies are needed to assess the efficacy and safety of this membrane in vivo.

Polymeric Based Hydrogel Membranes for Biomedical Applications

The development of biomedical applications is a transdisciplinary field that in recent years has involved researchers from chemistry, pharmacy, medicine, biology, biophysics, and biomechanical engineering. The fabrication of biomedical devices requires the use of biocompatible materials that do not damage living tissues and have some biomechanical characteristics. The use of polymeric membranes, as materials meeting the above-mentioned requirements, has become increasingly popular in recent years, with outstanding results in tissue engineering, for regeneration and replenishment of tissues constituting internal organs, in wound healing dressings, and in the realization of systems for diagnosis and therapy, through the controlled release of active substances. The biomedical application of hydrogel membranes has had little uptake in the past due to the toxicity of cross-linking agents and to the existing limitations regarding gelation under physiological conditions, but now it is proving to be a very promising field This review presents the important technological innovations that the use of membrane hydrogels has promoted, enabling the resolution of recurrent clinical problems, such as post-transplant rejection crises, haemorrhagic crises due to the adhesion of proteins, bacteria, and platelets on biomedical devices in contact with blood, and poor compliance of patients undergoing long-term drug therapies.

Fabrication of hierarchical porous ethyl cellulose fibrous membrane by electro-centrifugal spinning for drug delivery systems with excellent integrated properties

Drug delivery systems (DDSs) based on micro-and nano- fibrous membrane have been developed for decades, in which great attention has been focused on achieving controlled drug release. However, the study on the integrated performance of these drug-loaded membranes in the use of in-vitro drug delivery dressing is lacking, as clinical medication also needs consideration from the perspectives of wound safety and patient convenience. Herein, a trilayered hierarchical porous ethyl cellulose (EC) fibrous membrane based DDS (EC-DDS) was developed by electro-centrifugal spinning. Significantly, the hierarchical porous structure of the EC-DDSs with high specific surface area (34.3 m²g^-1) and abundant long-regulative micro-and nano- channels demonstrated its merits in improving the hydrophobicity (long-term splash resistance (CA > 130°) and prolonging the drug release (the release time of ~80 % tetracycline hydrochloride (TCH) prolonged from 10 min to 24 h). Meanwhile, the trilayered EC-DDS also revealed excellent biocompatibility, antibacterial activity, air permeability, moisture permeability, water absorption capacity, mechanical strength, and flexibility. With these excellent integrated features, the EC-DDS could prevent external fluids, avoid infection, and provide comfort. Furthermore, this work also provides a new guide for the high-efficiency fabrication of porous fibrous membranes.

Recent advances in encapsulation of fat-soluble vitamins using polysaccharides, proteins, and lipids: A review on delivery systems, formulation, and industrial applications

Fat-soluble vitamins (FSVs) offer a range of beneficial properties as important nutrients in human nutrition. However, the high susceptibility to environmental conditions such as high temperature, light, and oxygen leads to the degradation of these compounds. This review highlights the different formulations underlying the encapsulation of FSVs in biopolymer (polysaccharide and protein) and lipid-based micro or nanocarriers for potential applications in food and pharmaceutical industries. In particular, the function of these carrier systems in terms of encapsulation efficiency, stability, bioavailability, and bio-accessibility is critically discussed. Recently, tremendous attention has been paid to encapsulating FSVs in commercial applications. According to the chemical nature of the active compound, the vigilant selection of delivery formulation, method of encapsulation, and final application (type of food) are the key important factors to be considered in the encapsulation of FSVs to ensure a high loading capacity, stability, bioavailability, and bio-accessibility. Future studies are recommended on the effect of different vitamin types and micro and nano encapsulate sizes on bioaccessibility and biocompatibility through in vitro/in vivo studies. Moreover, the toxicity and safety evaluation of encapsulated FSVs in human health should be evaluated before commercial application in food and pharmaceuticals.

Reduced graphene oxide-enriched chitosan hydrogel/cellulose acetate-based nanofibers application in mild hyperthermia and skin regeneration

Asymmetric wound dressings have captured researchers' attention due to their ability to reproduce the structural and functional properties of the skin layers. Furthermore, recent studies also report the benefits of using near-infrared (NIR) radiation-activated photothermal therapies in treating infections and chronic wounds. Herein, a chitosan (CS) and reduced graphene oxide (rGO) hydrogel (CS_rGO) was combined with a polycaprolactone (PCL) and cellulose acetate (CA) electrospun membrane (PCL_CA) to create a new NIR-responsive asymmetric wound dressing. The rGO incorporation in the hydrogel increased the NIR absorption capacity and allowed a mild hyperthermy effect, a temperature increase of 12.4 °C when irradiated with a NIR laser. Moreover, the PCL_CA membrane presented a low porosity and hydrophobic nature, whereas the CS_rGO hydrogel showed the ability to provide a moist environment, prevent exudate accumulation and allow gaseous exchanges. Furthermore, the in vitro data demonstrate the capacity of the asymmetric structure to act as a barrier against bacteria penetration as well as mediating a NIR-triggered antibacterial effect. Additionally, human fibroblasts were able to adhere and proliferate in the CS_rGO hydrogel, even under NIR laser irradiation, presenting cellular viabilities superior to 90 %. Altogether, our data support the application of the NIR-responsive asymmetric wound dressings for skin regeneration.

Effect of surface structure on the antithrombogenicity performance of poly(-caprolactone)-cellulose acetate small-diameter tubular scaffolds

Small-diameter artificial blood vessels have always faced the problem of thrombosis. In this research, three types of poly(-caprolactone)-cellulose acetate (PCL-CA) composite nanofiber membranes were prepared by various collectors to make into a tubular scaffold with a 4.5-mm diameter. The collector consisted of two sizes of stainless steel wire mesh large-mesh (LM) and small-mesh (SM), respectively. There is also a random flat (RF) that acts as the third type collector. The nanofiber membrane's surface structure mimicked the collectors' surface morphology, they named LM, SM and RF scaffolds. The water contact angles of RF and LM scaffolds are 126.5° and 105.5°, and the distinct square-groove construction greatly improves the contact angle of LM. The tubular scaffolds' radial mechanical property test demonstrated that the large-mesh (LM) tubular scaffold enhanced the strain and tensile strength; the tensile strength and strain are 30 % and 148 % higher than that of the random-flat (RF) tubular scaffold, respectively. The suture retention strength value of the LM tubular scaffold was 103 % higher than that of the RF tubular scaffold. The cytotoxicity and antithrombogenicity performance were also evaluated, the LM tubular scaffold has 88 % cell viability, and the 5-min blood coagulation index (BCI) value was 89 %, which is much higher than other tubular scaffolds. The findings indicate that changing the tubular scaffold's surface morphology cannot only enhance the mechanical and hydrophilic properties but also increase cell survival and antithrombogenicity performance. Thus, the development of a small-diameter artificial blood vessel will be a big step toward solving the problem on thrombosis. Furthermore, artificial blood vessel is expected to be a candidate material for biomedical applications.

Polymeric Membranes for Biomedical Applications

Polymeric membranes are selective materials used in a wide range of applications that require separation processes, from water filtration and purification to industrial separations. Because of these materials' remarkable properties, namely, selectivity, membranes are also used in a wide range of biomedical applications that require separations. Considering the fact that most organs (apart from the heart and brain) have separation processes associated with the physiological function (kidneys, lungs, intestines, stomach, etc.), technological solutions have been developed to replace the function of these organs with the help of polymer membranes. This review presents the main biomedical applications of polymer membranes, such as hemodialysis (for chronic kidney disease), membrane-based artificial oxygenators (for artificial lung), artificial liver, artificial pancreas, and membranes for osseointegration and drug delivery systems based on membranes.

Therapeutic applications of electrospun nanofibers impregnated with various biological macromolecules for effective wound healing strategy - A review

A Non-healing infected wound is an ever-growing global epidemic, with increasing burden of mortality rates and management costs. The problems of chronic wound infections and their outcomes will continue as long as their underlying causes like diabetic wounds grow and spread. Commercial wound therapies employed have limited potential that inhibits pivotal functions and tissue re-epithelialization properties resulting in wound infections. Nanomaterial based drug delivery formulations involving biological macromolecules are developing areas of interest in wound healing applications which are utilized in the re-epithelialization of skin with cost-effective preparations. Research conducted on nanofibers has shown enhanced skin establishment with improved cell proliferation and growth and delivery of bioactive organic molecules at the wound site. However, drug targeted delivery with anti-scarring properties and tissue regeneration aspects have not been updated and discussed in the case of macromolecule impregnated nanofibrous mats. Hence, this review focuses on the brief concepts of wound healing and wound management, therapeutic commercialized wound dressings currently available in the field of wound care, effective electrospun nanofibers impregnated with different biological macromolecules and advancement of nanomaterials for tissue engineering have been discussed. These new findings will pave the way for producing anti-scarring high effective wound scaffolds for drug delivery.

Fortification by design: A rational approach to designing vitamin D delivery systems for foods and beverages

Over the past few decades, vitamin D deficiency has been recognized as a serious global public health challenge. The World Health Organization has recommended fortification of foods with vitamin D, but this is often challenging because of its low water solubility, poor chemical stability, and low bioavailability. Studies have shown that these challenges can be overcome by encapsulating vitamin D within well-designed delivery systems containing nanoscale or microscale particles. The characteristics of these particles, such as their composition, size, structure, interfacial properties, and charge, can be controlled to attain desired functionality for specific applications. Recently, there has been great interest in the design, production, and application of vitamin-D loaded delivery systems. Many of the delivery systems reported in the literature are unsuitable for widespread application due to the complexity and high costs of the processing operations required to fabricate them, or because they are incompatible with food matrices. In this article, the concept of "fortification by design" is introduced, which involves a systematic approach to the design, production, and testing of colloidal delivery systems for the encapsulation and fortification of oil-soluble vitamins, using vitamin D as a model. Initially, the challenges associated with the incorporation of vitamin D into foods and beverages are reviewed. The fortification by design concept is then described, which involves several steps: (i) selection of appropriate vitamin D form; (ii) selection of appropriate food matrix; (iii) identification of appropriate delivery system; (iv) identification of appropriate production method; (vii) establishment of appropriate testing procedures; and (viii) system optimization.

ECM Mimicking Biodegradable Nanofibrous Scaffold Enriched with Curcumin/ZnO to Accelerate Diabetic Wound Healing via Multifunctional Bioactivity

Introduction

Foot ulceration is one of the most severe and debilitating complications of diabetes, which leads to the cause of non-traumatic lower-extremity amputation in 15-24% of affected individuals. The healing of diabetic foot (DF) is a significant therapeutic problem due to complications from the multifactorial healing process. Electrospun nanofibrous scaffold loaded with various wound dressing materials has excellent wound healing properties due to its multifunctional action.

Purpose

This work aimed to develop and characterize chitosan (CS)-polyvinyl alcohol (PVA) blended electrospun multifunctional nanofiber loaded with curcumin (CUR) and zinc oxide (ZnO) to accelerate diabetic wound healing in STZ-induced diabetic rats.

Results

In-vitro characterization results revealed that nanofiber was fabricated successfully using the electrospinning technique. SEM results confirmed the smooth surface with web-like fiber nanostructure diameter ranging from 200 - 250 nm. An in-vitro release study confirmed the sustained release of CUR and ZnO for a prolonged time. In-vitro cell-line studies demonstrated significantly low cytotoxicity of nanofiber in HaCaT cells. Anti-bacterial studies demonstrated good anti-bacterial and anti-biofilm activities of nanofiber. In-vivo animal studies demonstrated an excellent wound-healing efficiency of the nanofibers in STZ-induced diabetic rats. Furthermore, the ELISA assay revealed that the optimized nanofiber membrane terminated the inflammatory phases successfully by downregulating the pro-inflammatory cytokines (TNF-α, MMP-2, and MMP-9) in wound healing. In-vitro and in-vivo studies conclude that the developed nanofiber loaded with bioactive material can promote diabetic wound healing efficiently via multifunction action such as the sustained release of bioactive molecules for a prolonged time of duration, proving anti-bacterial/anti-biofilm properties and acceleration of cell migration and proliferation process during the wound healing.

Discussion

CUR-ZnO electrospun nanofibers could be a promising drug delivery platform with the potential to be scaled up to treat diabetic foot ulcers effectively.

Encapsulation of Grape (Vitis vinifera L.) Pomace Polyphenols in Soybean Extract-Based Hydrogel Beads as Carriers of Polyphenols and pH-Monitoring Devices

In this work, novel bio-based hydrogel beads were fabricated by using soybean extract as raw waste material loaded with Lambrusco extract, an Italian grape cultivar. The phenolic profile and the total amount of anthocyanins from the Lambrusco extract were evaluated before encapsulating it in soybean extract-based hydrogels produced through an ionotropic gelation technique. The physical properties of the produced hydrogel beads were then studied in terms of their morphological and spectroscopic properties. Swelling degree was evaluated in media with different pH levels. The release kinetics of Lambrusco extract were then studied over time as a function of pH of the release medium, corroborating that the acidity/basicity could affect the release rate of encapsulated molecules, as well as their counter-diffusion. The pH-sensitive properties of wine extract were studied through UV-Vis spectroscopy while the colorimetric responses of loaded hydrogel beads were investigated in acidic and basic solutions. Finally, in the framework of circular economy and sustainability, the obtained data open routes to the design and fabrication of active materials as pH-indicator devices from food industry by-products.

Dual-Functional Nanofibrous Patches for Accelerating Wound Healing

Bacterial infections and inflammation are two main factors for delayed wound healing. Coaxial electrospinning nanofibrous patches, by co-loading and sequential co-delivering of anti-bacterial and anti-inflammation agents, are promising wound dressing for accelerating wound healing. Herein, curcumin (Cur) was loaded into the polycaprolactone (PCL) core, and broad-spectrum antibacterial tetracycline hydrochloride (TH) was loaded into gelatin (GEL) shell to prepare PCL-Cur/GEL-TH core-shell nanofiber membranes. The fibers showed a clear co-axial structure and good water absorption capacity, hydrophilicity and mechanical properties. In vitro drug release results showed sequential release of Cur and TH, in which the coaxial mat showed good antioxidant activity by DPPH test and excellent antibacterial activity was demonstrated by a disk diffusion method. The coaxial mats showed superior biocompatibility toward human immortalized keratinocytes. This study indicates a coaxial nanofiber membrane combining anti-bacterial and anti-inflammation agents has great potential as a wound dressing for promoting wound repair.

Electrospun Nanofiber Composites for Drug Delivery: A Review on Current Progresses

A medication’s approximate release profile should be sustained in order to generate the desired therapeutic effect. The drug’s release site, duration, and rate must all be adjusted to the drug’s therapeutic aim. However, when designing drug delivery systems, this may be a considerable hurdle. Electrospinning is a promising method of creating a nanofibrous membrane since it enables drugs to be placed in the nanofiber composite and released over time. Nanofiber composites designed through electrospinning for drug release purposes are commonly constructed of simple structures. This nanofiber composite produces matrices with nanoscale fiber structure, large surface area to volume ratio, and a high porosity with small pore size. The nanofiber composite’s large surface area to volume ratio can aid with cell binding and multiplication, drug loading, and mass transfer processes. The nanofiber composite acts as a container for drugs that can be customized to a wide range of drug release kinetics. Drugs may be electrospun after being dissolved or dispersed in the polymer solution, or they can be physically or chemically bound to the nanofiber surface. The composition and internal structure of the nanofibers are crucial for medicine release patterns.

A Study on the Effect of Nanoscale MgO and Hydrogen Bonding in Nanofiber Mats for the Controlled Drug Release along with In Vitro Breast Cancer Cell Line and Antimicrobial Studies

Nanosized metal oxide-incorporated drug carriers have received significant attention due to their biocompatibility, mechanical strength, controlled drug release, and biodegradability. Herein, an attempt was made to fabricate polycaprolactone-based electrospun nanofiber mats involving the 5-fluorouracil (5Fu) drug, MgO nanoparticle, methyl cellulose, and polyethylene glycol. The chemical interactions, surface wettability, mechanical properties, structural and morphological changes, and thermal stability were studied by the respective analyses. The ionic interaction between 5Fu, MgO, and polymers were found to be responsible for the controlled drug release. Zero-order kinetic and model data also revealed that a controlled drug release pattern was observed in a period of 16 days. Furthermore, the nanofiber mats were subjected to cytotoxicity studies against MDA-MB-231 cancer cell line and the results showed higher cytotoxicity in a short time of 24 h and less toxicity to normal L929 fibroblast cell line. The apoptosis in cancer cell lines was also tested by AO/PI staining assay and confirmed by fluorescence microscopy. In addition, the growth inhibition of several bacterial and fungal strains was tested for the mats and the results exhibited good inhibition activity. Hence, the reported nanofiber drug carrier was found to be an efficient implant for the controlled release of anticancer drug along with other significant properties.

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.

Controlled release of vitamin D3 using a nanocellulose-based membrane

Epidemiological studies show that a significant fraction of the global population presents low levels of vitamin D₃. In order to address this problem, one way to administer the vitamin is to incorporate it in novel drug delivery systems, such as transdermal devices. A possible substance for this purpose is cellulose, which has a long history of use in the health area. However, the application of nanostructured cellulose membranes, as local drug delivery systems, remains a challenge. To develop a crystalline nanocellulose membrane as a new tool for the release of vitamin D₃. A new nanostructured membrane containing nanocellulose extracted from cotton linter and vitamin D₃ was produced using the “casting” technique. The membrane was characterized using high-resolution scanning electron microscopy (FEG-SEM) and Fourier transform infrared spectroscopy (FT-IR). The kinetics of vitamin release was quantified using molecular spectroscopy (UV–Vis). The FT-IR spectra showed the presence of all the active components in the membrane sample, without structural alterations or the formation of new bonds. The FEG-SEM images showed the presence of vitamin crystals on the surface and in the interior of the membrane. The release of vitamin D₃ occurred in a sustained manner, obtaining 3029 IU mL⁻¹ of vitamin D₃ in 60 min. The findings demonstrated that the membrane could be used for the sustained release of vitamin D₃. This new biomaterial has potential as a new model for vitamin supplementation in individuals with vitamin D₃ deficiency.

Piperine-loaded electrospun nanofibers, an implantable anticancer controlled delivery system for postsurgical breast cancer treatment

Tumorectomy followed by radiotherapy, hormone, and chemotherapy, are the current mainstays for breast cancer treatment. However, these strategies have systemic toxicities and limited treatment outcomes. Hence, there is a crucial need for a novel controlled release delivery system for implantation following tumor resection to effectively prevent recurrence. Here, we fabricated polycaprolactone (PCL)-based electrospun nanofibers containing piperine (PIP), known for chemopreventive and anticancer activities, and also evaluated the impact of collagen (Coll) incorporation into the matrices. In addition to physicochemical characterization such as morphology, hydrophilicity, drug content, release properties, and mechanical behaviors, fabricated nanofibers were investigated in terms of cytotoxicity and involved mechanisms in MCF-7 and 4T1 breast tumor cell lines. In vivo antitumor study was performed in 4T1 tumor-bearing mice. PIP-PCL⁷⁵-Coll²⁵ nanofiber was chosen as the optimum formulation due to sustained PIP release, good mechanical performance, and superior cytotoxicity. Demonstrating no organ toxicity, animal studies confirmed the superiority of locally administered PIP-PCL⁷⁵-Coll²⁵ nanofiber in terms of inhibition of growth tumor, induction of apoptosis, and reduction of cell proliferation compared to PIP suspension, blank nanofiber, and the control. Taken together, we concluded that PIP-loaded nanofibers can be introduced as a promising treatment for implantation upon breast tumorectomy.

Electrospun Biomimetic Multifunctional Nanofibers Loaded with Ferulic Acid for Enhanced Antimicrobial and Wound-Healing Activities in STZ-Induced Diabetic Rats

Diabetic foot ulceration is the most distressing complication of diabetes having no standard therapy. Nanofibers are an emerging and versatile nanotechnology-based drug-delivery system with unique wound-healing properties. This study aimed to prepare and evaluate silk-sericin based hybrid nanofibrous mats for diabetic foot ulcer. The nanofibrous mats were prepared by electrospinning using silk sericin mixed with different proportions of polycaprolactone (PCL) and cellulose acetate (CA) loaded with ferulic acid (FA). The in vitro characterizations, such as surface morphology, mechanical properties, swelling behavior, biodegradability, scanning electron microscopy, and drug release were carried out. The SEM images indicated that nanofibers formed with varied diameters, ranging from 100 to 250 nm, and their tensile strength was found to range from 7 to 15 MPa. In vitro release demonstrated that the nanofibers sustained FA release over an extended time of period. In vitro cytotoxicity showed that the nanofibers possessed a lower cytotoxicity in HaCaT cells. The in vivo wound-healing studies demonstrated an excellent wound-healing efficiency of the nanofibers in diabetic rats. Furthermore, the histopathological studies showed the nanofibers' ability to restore the skin's normal structure. Therefore, it was concluded that the prepared silk-sericin-based hybrid nanofibers loaded with FA could be a promising drug-delivery platform for the effective treatment of diabetic foot ulcers.

Pro-oxidant vitamin C mechanistically exploits p66Shc/Rac1GTPase pathway in inducing cytotoxicity

P66Shc is the master regulator of oxidative stress whose pro-oxidant functioning is governed by ser36 phosphorylation. Phosphorylated p66Shc via Rac1GTPase activation modulates ROS levels which in turn influence its pro-oxidative functions. Vitamin C at higher concentrations exhibits cytotoxic activity in various cancers, inducing ROS mediated cell death via pro-apoptotic mechanisms. Here we show a novel role of p66Shc in mediating pro-oxidant activity of vitamin C. Effect of vitamin C on the viability of breast cancer and normal cells was studied. High doses of vitamin C decreased viability of cancerous cells but not normal cells. Docking study displayed significant binding affinity of vitamin C with p66Shc PTB domain. Western blot results suggest that vitamin C not only enhances p66Shc expression but also induces its ser36 phosphorylation. Vitamin C at high doses was also found to activate Rac1, enhance ROS production and induce apoptosis. Interestingly, ser36 phosphorylation mutant transfection and pretreatment with antioxidant N-acetylcysteine results indicate that vitamin C induced Rac1 activation, ROS production and apoptosis is p66Shc ser36 phosphorylation dependent. Overall, results highlight that vitamin C mechanistically explores p66Shc/Rac1 pathway in inducing apoptosis and thus can pave a way to use this pathway as a potential therapeutic target in breast cancers.

Multifunctional Biomimetic Nanofibrous Scaffold Loaded with Asiaticoside for Rapid Diabetic Wound Healing

Diabetes mellitus is a chronic disease with a high mortality rate and many complications. A non-healing diabetic foot ulcer (DFU) is one the most serious complications, leading to lower-extremity amputation in 15% of diabetic patients. Nanofibers are emerging as versatile wound dressing due to their unique wound healing properties, such as a high surface area to volume ratio, porosity, and ability to maintain a moist wound environment capable of delivering sustained drug release and oxygen supply to a wound. The present study was aimed to prepare and evaluate a polyvinyl alcohol (PVA)–sodium alginate (SA)–silk fibroin (SF)-based multifunctional nanofibrous scaffold loaded with asiaticoside (AT) in diabetic rats. The SEM findings showed that fibers’ diameters ranged from 100–200 nm, and tensile strengths ranged from 12.41–16.80 MPa. The crosslinked nanofibers were sustained AT over an extended period. The MTT and scratch assay on HaCat cells confirmed low cytotoxicity and significant cell migration, respectively. Antimicrobial tests revealed an excellent anti-microbial efficacy against P. aeruginosa and S. aureus bacteria. In-vivo study demonstrated better wound healing efficacy in diabetic rats. In addition, the histopathological studies showed its ability to restore the normal structure of the skin. The present study concluded that developed multifunctional nanofibers have a great potential for diabetic wound healing applications.

Nanocarriers for Sustainable Active Packaging: An Overview during and Post COVID-19

Lockdown has been installed due to the fast spread of COVID-19, and several challenges have occurred. Active packaging was considered a sustainable option for mitigating risks to food systems during COVID-19. Biopolymeric-based active packaging incorporating the release of active compounds with antimicrobial and antioxidant activity represents an innovative solution for increasing shelf life and maintaining food quality during transportation from producers to consumers. However, food packaging requires certain physical, chemical, and mechanical performances, which biopolymers such as proteins, polysaccharides, and lipids have not satisfied. In addition, active compounds have low stability and can easily burst when added directly into biopolymeric materials. Due to these drawbacks, encapsulation into lipid-based, polymeric-based, and nanoclay-based nanocarriers has currently captured increased interest. Nanocarriers can protect and control the release of active compounds and can enhance the performance of biopolymeric matrices. The aim of this manuscript is to provide an overview regarding the benefits of released active compound-loaded nanocarriers in developing sustainable biopolymeric-based active packaging with antimicrobial and antioxidant properties. Nanocarriers improve physical, chemical, and mechanical properties of the biopolymeric matrix and increase the bioactivity of released active compounds. Furthermore, challenges during the COVID-19 pandemic and a brief post-COVID-19 scenario were also mentioned.

Vitamin D3/vitamin K2/magnesium-loaded polylactic acid/tricalcium phosphate/polycaprolactone composite nanofibers demonstrated osteoinductive effect by increasing Runx2 via Wnt/β-catenin pathway

Vitamin D₃, vitamin K₂, and Mg (10%, 1.25%, and 5%, w/w, respectively)-loaded PLA (12%, w/v) (TCP (5%, w/v))/PCL (12%, w/v) 1:1 (v/v) composite nanofibers (DKMF) were produced by electrospinning method (ES) and their osteoinductive effects were investigated in cell culture test. Neither pure nanofibers nor DKMF caused a significant cytotoxic effect in fibroblasts. The induction of the stem cell differentiation into osteogenic cells was observed in the cell culture with both DKMF and pure nanofibers, separately. Vitamin D_3, vitamin K₂, and magnesium demonstrated to support the osteogenic differentiation of mesenchymal stem cells by expressing Runx2, BMP2, and osteopontin and suppressing PPAR-γ and Sox9. Therefore, the Wnt/β-catenin signaling pathway was activated by DKMF. DKMF promoted large axonal sprouting and needle-like elongation of osteoblast cells and enhanced cellular functions such as migration, infiltration, proliferation, and differentiation after seven days of incubation using confocal laser scanning microscopy. The results showed that DKMF demonstrated sustained drug release for 144 h, tougher and stronger structure, higher tensile strength, increased water up-take capacity, decreased degradation ratio, and slightly lower Tm and Tg values compared to pure nanofibers. Consequently, DKMF is a promising treatment approach in bone tissue engineering due to its osteoinductive effects.

Orodispersible Membranes from a Modified Coaxial Electrospinning for Fast Dissolution of Diclofenac Sodium

The dissolution of poorly water-soluble drugs has been a longstanding and important issue in pharmaceutics during the past several decades. Nanotechnologies and their products have been broadly investigated for providing novel strategies for resolving this problem. In the present study, a new orodispersible membrane (OM) comprising electrospun nanofibers is developed for the fast dissolution of diclofenac sodium (DS). A modified coaxial electrospinning was implemented for the preparation of membranes, during which an unspinnable solution of sucralose was explored as the sheath working fluid for smoothing the working processes and also adjusting the taste of membranes. SEM and TEM images demonstrated that the OMs were composed of linear nanofibers with core-sheath inner structures. XRD and ATR-FTIR results suggested that DS presented in the OMs in an amorphous state due to the fine compatibility between DS and PVP. In vitro dissolution measurements and simulated artificial tongue experiments verified that the OMs were able to release the loaded DS in a pulsatile manner. The present protocols pave the way for the fast dissolution and fast action of a series of poorly water-soluble active ingredients that are suitable for oral administration.