Nanoparticles incorporated in nanofibers using electrospinning: A novel nano-in-nano delivery system

Recent advances of electrospun strategies in topical products encompassing skincare and dermatological treatments

As the potential applications of electrospinning in healthcare continue to be explored, along with advancements in industrial-scale solutions and the emergence of portable electrospinning devices, some researchers have explored electrospinning technology in topical products, including its application in skincare, such as facial masks, beauty patches, sunscreen, and dermatological treatments for conditions like atopic dermatitis, psoriasis, acne, skin cancer, etc. In this review, we first outline the fundamental principles of electrospinning and provide an overview of existing solutions for large-scale production and the components and functionalities of portable spinning devices. Based on the essential functionalities required for skincare products and the mechanisms and treatment methods for the aforementioned dermatological diseases, we summarize the potential advantages of electrospinning technology in these areas, including encapsulation, sustained release, large surface area, and biocompatibility, among others. Furthermore, considering the further commercialization and clinical development of electrospinning technology, we offer our insights on current challenges and future perspectives in these areas, including issues such as ingredients, functionality, residue concerns, environmental impact, and efficiency issues.

Preparation and characterization of PVA/chitosan nanofibers loaded with Dragon's blood or poly helixan as wound dressings

Nanofibers have been investigated in regenerative medicine. Dragon's blood (DB)- and poly helixan PF (PHPF) are natural materials used in cosmetics. Herein, we generated DB- and PHPF-loaded polyvinyl alcohol/chitosan (PVA/CS/DB and PVA/CS/PHPF, respectively) nanofibers. PVA/CS/DB and PVA/CS/PHPF nanofibers had an average diameter of 547.5 ± 17.13 and 521 ± 24.67 nm, respectively as assessed by SEM, and a degradation rate of 43.1 and 47.6 % after 14 days, respectively. PVA/CS/DB and PVA/CS/PHPF nanofibers had a hemolysis rate of 0.10 and 0.39 %, respectively, and a water vapor transmission rate of ∼2200 g.m-2.day-1. These nanofibers exhibited favorable antimicrobial activity against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Bacillus subtilis in vitro. PVA/CS/DB and PVA/CS/PHPF nanofibers demonstrated a sustained release of 77.91 and 76.55 % over 72 h. PVA/CS/DB and PVA/CS/PHPF nanofibers had a high rate of cytocompatibility and significantly improved the viability of NIH/3T3 cells as compared with free drugs or unloaded nanofibers. Histological inspection via H&E and Verhoeff's staining demonstrated PVA/CS/DB and PVA/CS/PHPF nanofibers enhanced the wound healing and damaged tissue recovery of unsplinted wound models by promoting epithelial layer formation, collagen deposition, and enhancing the presence of fibroblasts. Conclusively, PVA/CS/DB and PVA/CS/PHPF can be introduced as potential wound dressing candidates with favorable properties.

Temozolomide nano-in-nanofiber delivery system with sustained release and enhanced cellular uptake by U87MG cells

OBJECTIVE

The study was aimed at formulating temozolomide (TMZ) loaded gelatin nanoparticles (GNPs) encapsulated into polyvinyl alcohol (PVA) nanofibers (TMZ-GNPs-PVA NFs) as the nano-in-nanofiber delivery system. The secondary objective was to explore the sustained releasing ability of this system and to assess its enhanced cellular uptake against U87MG glioma cells in vitro.

SIGNIFICANCE

Nano-in-nanofibers are the emerging drug delivery systems for treating a wide range of diseases including cancers as they overcome the challenges experienced by nanoparticles and nanofibers alone.

METHODS

The drug-loaded GNPs were formulated by one-step desolvation method. The Design of Experiments (DoE) was used to optimize nanoparticle size and entrapment efficiency. The optimized drug-loaded nanoparticles were then encapsulated within nanofibers using blend electrospinning technique. The U87MG glioma cells were used to investigate the uptake of the formulation.

RESULTS

A 32 factorial design was used to optimize the mean particle size (145.7 nm) and entrapment efficiency (87.6%) of the TMZ-loaded GNPs which were subsequently ingrained into PVA nanofibers by electrospinning technique. The delivery system achieved a sustained drug release for up to seven days (in vitro). The SEM results ensured that the expected nano-in-nanofiber delivery system was achieved. The uptake of TMZ-GNPs-PVA NFs by cells was increased by a factor of 1.964 compared to that of the pure drug.

CONCLUSION

The nano-in-nanofiber drug delivery system is a potentially useful therapeutic strategy for the management of glioblastoma multiforme.

OXPHOS-targeted nanoparticles for boosting photodynamic therapy against hypoxia tumor

Hypoxia as an inherent feature in tumors is firmly associated with unsatisfactory clinical outcomes of photodynamic therapy (PDT) since the lack of oxygen leads to ineffective reactive oxygen species (ROS) productivity for tumor eradication. In this study, an oxidative phosphorylation (OXPHOS) targeting nanoplatform was fabricated to alleviate hypoxia and enhance the performance of PDT by encapsulating IR780 and OXPHOS inhibitor atovaquone (ATO) in triphenylphosphine (TPP) modified poly(ethylene glycol) methyl ether-block-poly(L-lactide-co-glycolide) (mPEG-PLGA) nanocarriers (TNPs/IA). ATO by interrupting the electron transfer in OXPHOS could suppress mitochondrial respiration of tumor cells, economising on oxygen for the generation of ROS. Benefiting from the mitochondrial targeting function of TPP, ATO was directly delivered to its site of action to obtain highlighted effect at a lower dosage. Furthermore, positioning the photosensitizer IR780 to mitochondria, a more vulnerable organelle to ROS, was a promising method to attenuate the spatiotemporal limitation of ROS caused by its short half-life and narrow diffusion radius. As a result, TNPs/IA exhibited accurate subcellular localization, lead to the collapse of ATP production by damaging mitochondrion and elicited significant antitumor efficacy via oxygen-augmented PDT in the HeLa subcutaneous xenograft model. Overall, TNPs/IA was a potential strategy in photodynamic eradication of tumors.

Application of nanofiber-based drug delivery systems in improving anxiolytic effect of new 1,2,3-triazolo-1,4-benzodiazepine derivatives

Anxiety disorders are highly prevalent worldwide and can affect people of all ages, genders and backgrounds. Much efforts and resources have been directed at finding new anxiolytic agents and drug delivery systems (DDSs) especially for cancer patients to enhance targeted drug delivery, reduce drug adverse effects, and provide an analgesic effect. The aim of this study was (1) to design and develop novel nanofiber-based DDSs intended for the oral administration of new 1,2,3-triazolo-1,4-benzodiazepines derivatives, (2) to investigate the physical solid-state properties of such drug-loaded nanofibers, and (3) to gain knowledge of the anxiolytic activity of the present new benzodiazepines in rodents in vivo. The nanofibers loaded with 1,2,3-triazolo-1,4-benzodiazepine derivatives were prepared by means of electrospinning (ES). Field-emission scanning electron microscopy and attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy were used for the physicochemical characterization of nanofibers. The anxiolytic activity of new derivatives and drug-loaded nanofibers was studied with an elevated plus maze test and light-dark box test. New 1,2,3-triazolo-1,4-benzodiazepine derivatives showed a promising anxiolytic effect in mice with clear changes in behavioral reactions in both tests. The nanofiber-based DDS was found to be feasible in the oral delivery of the present benzodiazepine derivatives. The nanofibers generated by means of ES presented the diameter in a nanoscale, uniform fiber structure, capacity for drug loading, and the absence of defects. The present findings provide new insights in the drug treatment of anxiety disorders with new benzodiazepine derivatives.

Janus silk fibroin/polycaprolactone-based scaffold with directionally aligned fibers and porous structure for bone regeneration

To promote bone repair, it is desirable to develop three-dimensional multifunctional fiber scaffolds. The densely stacked and tightly arranged conventional two-dimensional electrospun fibers hinder cell penetration into the scaffold. Most of the existing three-dimensional structural materials are isotropic and monofunctional. In this research, a Janus nanofibrous scaffold based on silk fibroin/polycaprolactone (SF/PCL) was fabricated. SF-encapsulated SeNPs demonstrated stability and resistance to aggregation. The outside layer (SF/PCL/Se) of the Janus nanofiber scaffold displayed a structured arrangement of fibers, facilitating cell growth guidance and impeding cell invasion. The inside layer (SF/PCL/HA) featured a porous structure fostering cell adhesion. The Janus fiber scaffold containing SeNPs notably suppressed S. aureus and E. coli activities, correlating with SeNPs concentration. In vitro, findings indicated considerable enhancement in alkaline phosphatase (ALP) activity of MC3T3-E1 osteoblasts and upregulation of genes linked to osteogenic differentiation with exposure to the SF/PCL/HA/Se Janus nanofibrous scaffold. Moreover, in vivo, experiments demonstrated successful critical bone defect repair in mouse skulls using the SF/PCL/HA/Se Janus nanofiber scaffold. These findings highlight the potential of the SF/PCL-based Janus nanofibrous scaffold, integrating SeNPs and nHA, as a promising biomaterial in bone tissue engineering.

"Nano in Nano"-Incorporation of ZnO Nanoparticles into Cellulose Acetate-Poly(Ethylene Oxide) Composite Nanofibers Using Solution Blow Spinning

In this work, the preparation and characterization of composites from cellulose acetate (CA)-poly(ethylene oxide) (PEO) nanofibers (NFs) with incorporated zinc oxide nanoparticles (ZnO-NPs) using solution blow spinning (SBS) is reported. CA-PEO nanofibers were produced by spinning solution that contained a higher CA-to-PEO ratio and lower (equal) CA-to-PEO ratio. Nanoparticles were added to comprise 2.5% and 5% of the solution, calculated on the weight of the polymers. To have better control of the SBS processing conditions, characterization of the spinning suspensions is carried out, which reveals a decrease in viscosity (two- to eightfold) upon the addition of NPs. It is observed that this variation of viscosity does not significantly affect the mean diameters of nanofibers, but does affect the mode of the nanofibers' size distribution, whereby lower viscosity provides thinner fibers. FESEM-EDS confirms ZnO NP encapsulation into nanofibers, specifically into the CA component based on UV-vis studies, since the release of ZnO is not detected for up to 5 days in deionized water, despite the significant swelling of the material and accompanied dissolution of water-soluble PEO. Upon the dissolution of CA nanofibers into acetone, immediate release of ZnO is detected, both visually and by spectrometer. ATR-FTIR studies reveal interaction of ZnO with the CA component of composite nanofibers. As ZnO nanoparticles are known for their bioactivity, it can be concluded that these CA-PEO-ZnO composites are good candidates to be used in filtration membranes, with no loss of incorporated ZnO NPs or their release into an environment.

Mesoporous silica nanoparticles accommodating electrospun nanofibers as implantable local drug delivery system processed by cold atmospheric plasma and spin coating approaches

Nanofibers (NF) and nanoparticles are attractive for drug delivery to improve the drug bioavailability and administration. Easy manipulation of NF as macroscopic bulk material give rise to potential usages as implantable local drug delivery systems (LLDS) to overcome the failures of systemic drug delivery systems such as unmet personalized needs, side effects, suboptimal dosage. In this study, poly(ethylene glycol) polyethyleneimine (mPEG:PEI) copolymer blended polyϵ-caprolactone NFs, NFblendaccommodating mesoporous silica nanoparticles (MSN) as the implantable LLDS was achieved by employing spin coating and cold atmospheric plasma (CAP) as the post-process for accommodation on NFblend. The macroporous morphology, mechanical properties, wettability, andin vitrocytocompatibility of NFblendensured their potential as an implantable LLDS and superior features compared to neat NF. The electron microscopy images affirmed of NFblendrandom fiber (average diameter 832 ± 321 nm) alignments and accessible macropores before and after MSN@Cur accommodation. The blending of polymers improved the elongation of NF and the tensile strength which is attributed as beneficial for implantable LLDS. CAP treatment could significantly improve the wettability of NF observed by the contact angle changes from ∼126° to ∼50° which is critical for the accommodation of curcumin-loaded MSN (MSN@Cur) andin vitrocytocompatibility of NF. The combined CAP and spin coating as the post-processes was employed for accommodating MSN@Cur on NFblendwithout interfering with the electrospinning process. The post-processing aided fine-tuning of curcumin dosing (∼3 µg to ∼15 µg) per dose unit and sustained zero-order drug release profile could be achieved. Introducing of MSN@Cur to cells via LLDS promoted the cell proliferation compared to MSN@Cur suspension treatments and assigned as the elimination of adverse effects by nanocarriers by the dosage form integration. All in all, NFblend-MSN@Cur was shown to have high potential to be employed as an implantable LLDS. To the best of our knowledge, this is the first study in which mPEG:PEI copolymer blend NF are united with CAP and spin coating for accommodating nano-drug carriers, which allows for NF both tissue engineering and drug delivery applications.

Selenium nanoparticles incorporated in nanofibers media eliminate H1N1 activity: a novel approach for virucidal antiviral and antibacterial respiratory mask

The consecutive viral infectious outbreaks impose severe complications on public health besides the economic burden which led to great interest in antiviral personal protective equipment (PPE). Nanofiber-based respiratory mask has been introduced as a significant barrier to eliminate the airborne transmission from aerosols toward reduction the viral infection spreading. Herein, selenium nanoparticles incorporated in polyamide 6 nanofibers coated on spunbond nonwoven were synthesized via electrospinning technique (PA6@SeNPs), with an average diameter of 180 ± 2 nm. The nanofiber-coated media were tested for 0.3 μm particulate filtration efficiency based on Standard NIOSH (42 CFR 84). PA6@SeNPs had a pressure drop of 45 ± 2 Pa and particulate filtration efficiency of more than 97.33 which is comparable to the N95 respiratory mask. The bacterial killing efficiency of these nanofibers was 91.25% and 16.67% against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), respectively. Furthermore, the virucidal antiviral test for H1N1 infected Madin-Darby Canine Kidney cells (MDCK) exhibited TCID50 of 108.13, 105.88, and 105.5 for 2, 10, and 120 min of exposure times in comparison with 108.5, 107.5, and 106.5 in PA6 nanofibers as control sample. MTT assay indicated excellent biocompatibility of electrospun PA6@SeNP nanofibers on L292 cells. These results propose the PA6@SeNP nanofibers have a high potential to be used as an efficient layer in respiratory masks for protection against respiratory pathogens.

Electrospun Core-Sheath Nanofibers with a Cellulose Acetate Coating for the Synergistic Release of Zinc Ion and Drugs

Precisely modulating the synergistic release behavior of multiple bioactive substances has emerged as a formidable challenge in recent years. In this work, we successfully prepared core-sheath nanofibers, where a thin cellulose acetate (CA) coating enrobed the core. Curcumin (Cur) was encapsulated in the core layer as a model drug, while zinc oxide (ZnO) nanoparticles were loaded on the sheath layer. The prepared fiber exhibited a straight cylindrical morphology containing nanoparticles, and the distinct core-sheath nanostructure was demonstrated through transmission electron microscopy (TEM). X-ray diffraction (XRD) and Fourier transform infrared (FTIR) were conducted to study the physical state and compatibility among CA, Cur, and ZnO. Drug release data indicated that core-sheath nanofibers were able to decelerate the rate of drug release, and the thickness of the sheath layer increased in the presence of ZnO particles. Most remarkably, these core-sheath nanofibers exhibited the remarkable ability to sustain the release of drugs and zinc ion (Zn2+), the two-day synergistically release behavior leading to a significant increase in cell proliferation. This material preparation strategy for the synergistic and controlled release of two bioactive substances is instructive for the exploration of innovative and versatile drug delivery systems.

Biopolymeric nanofibrous scaffolds of poly(3-hydroxybuthyrate)/chitosan loaded with biogenic silver nanoparticle synthesized using curcumin and their antibacterial activities

The increasing prevalence of multi-drug resistant bacteria poses a significant threat to public health, especially in wound infections. Developing new bactericidal agents and treatment strategies is crucial to address this issue. In this study, biopolymeric nanofibrous scaffolds containing green-synthesized silver nanoparticles (AgNPs) with curcumin (CUR) were evaluated as antimicrobial materials for wound healing therapy. Firstly, CUR was utilized to synthesize AgNPs, which were then analyzed using various analytical methods. The microstructural analysis revealed that the biogenic AgNPs, which had a spherical shape and an average size of 19.83 nm, were uniformly anchored on PHB/CTS nanofibers. Then, the AgNPs with various content (0.25-1%wt) were incorporated into PHB/CTS matrix to enhance its wettability, thermal and bactericidal behaviors. The nanofibrous scaffolds were characterized by FT-IR, FE-SEM, TGA analysis and water contact angle measurement. Overall, the addition of CUR-AgNPs to the PHB/CTS matrix led to a reduction in fiber diameter, enhanced hydrophilicity and improved thermal properties. Additionally, antibacterial activity against Staphylococcus aureus and Escherichia coli was performed on samples of AgNPS and PHB/CTS/CUR-Ag. The synthesized AgNPs showed antibacterial activity against both microorganisms, especially against S. aureus. Higher concentrations of AgNPs in nanofibers led to a significant reduction in bacterial colony formation. The results displayed that PHB/CTS/CUR-AgNPs nanofibrous scaffolds could be a promising material for the biomedical applications such as wound healing.

Curcumin nanocrystals-in-nanofibres as a promising platform for the management of periodontal disease

It is estimated that nearly a half of the world's population over 30 years old suffer from some kind of periodontal disease (PD). Although preventable, PD can pose a significant health burden to patients, causing from pain and discomfort to disfigurement and death. The management of PD often requires surgical procedures accompanied of systemic antibiotic and anti-inflammatory treatments. Curcumin (CUR), a potent anti-inflammatory and antimicrobial active, has shown great promise in the management of PD; however, its effects are often limited by its low bioavailability. In this work, we report the development of electrospun nanofibres (NFs) loaded with CUR nanocrystals (NCs) for the management of PD. NCs of 100 nm were obtained by media milling and loaded into dissolving polyvinyl alcohol NFs using electrospinning. The resultant NCs-in-NFs dissolved in water spontaneously, releasing NCs with a particle size of ∼120 nm. The physiochemical characterisation of the systems indicated the absence of chemical interactions between drug and polymer, and nanofibres with an amorphous nature. In vitro release profiles demonstrated that the NCs had a significantly higher dissolution rate (∼100 % at day 40) than the control group (approximately 6 % at day 40), which consisted of NFs containing a physical mixture of the drug and stabiliser. Finally, mucosal deposition studies demonstrated a 10-fold higher capacity of the novel NCs-in-NFs system to deposit CUR ex vivo using excised neonatal porcine mucosal tissue, when compared to the control group.

Investigation of Luliconazole-Loaded Mucoadhesive Electrospun Nanofibers for Anticandidal Activity in the Management of Vaginal Candidiasis

In this study, we fabricated and evaluated luliconazole-loaded electrospun nanofibers for anticandidal activity in the management of vaginal candidiasis. Polycaprolactone (PCL)/gelatin nanofibers were designed by the electrospinning technique, and the Box-Behnken design (BBD) was adopted for optimization to get tailored fibers. The luliconazole (LCZ) drug was mixed into different concentrations (2.5, 5, 7.5, and 10%) of tea tree oil (TT oil) and loaded into the PCL/gelatin nanofibrous mats. The effective anticandidal potential of nanofiber samples were analyzed by the disk-diffusion method. Scanning electron microscopy (SEM), Fourier transform infrared (FTIR), differential scanning calorimetry (DSC), XRD analysis, and in silico study were performed. The entrapment efficiency, swelling degree, mechanical strength, contact angle, mucoadhesion, drug release, and permeation study were assessed. The average diameter of the PCL/gelatin-optimized nanofiber was 153 nm. SEM reflected that the fabricated nanofibers were uniform and bead-free. FTIR and DSC analyzed the interaction and physical entrapment of the drug in the polymeric fibers. The entrapment efficiency of the drug-loaded nanofiber was found to be 89.2 ± 0.8%. Maximum swelling percentages at 4 h were 40.8, 18.9, and 14.0% and contact angles were 46.5°, 62.95°, and 65.78° for the blank, TT oil-loaded, and drug-loaded nanofiber, respectively, which indicated the hydrophilic nature of the fibers. The drug-loaded nanofiber had a high tensile strength with satisfactory mucoadhesive property that led to its adhesion to the vaginal mucosa with no tear. The drug-loaded nanofiber had a cumulative drug release of 67.7 ± 3.4% in 48 h, and the 12.8 ± 0.53 mm of zone of inhibition (ZOI) in 48 h illustrated an effective anticandidal activity. The TT oil-loaded nanofiber also exhibited a small ZOI of 4.3 ± 0.30 mm, indicating a synergistic effect to the antifungal activity of the drug-loaded nanofiber. LCZ-loaded nanofibers can emerge as a novel approach for vaginal drug delivery in the treatment of candida infection. Thus, this pharmaceutical investigation can help in formulating preclinical and clinical models.

Structural Control of Nanofibers According to Electrospinning Process Conditions and Their Applications

Nanofibers have gained much attention because of the large surface area they can provide. Thus, many fabrication methods that produce nanofiber materials have been proposed. Electrospinning is a spinning technique that can use an electric field to continuously and uniformly generate polymer and composite nanofibers. The structure of the electrospinning system can be modified, thus making changes to the structure, and also the alignment of nanofibers. Moreover, the nanofibers can also be treated, modifying the nanofiber structure. This paper thoroughly reviews the efforts to change the configuration of the electrospinning system and the effects of these configurations on the nanofibers. Excellent works in different fields of application that use electrospun nanofibers are also introduced. The studied materials functioned effectively in their application, thereby proving the potential for the future development of electrospinning nanofiber materials.

Prolonged Anesthesia Effects of Locally Administered Ropivacaine via Electrospun Poly(caprolactone) Fibrous Membranes

Prolonged analgesia is important to safeguard the patient's comfort and safety during and after surgery in clinical practice. To meet the demand for prolonged analgesia, medical professionals often resort to increasing drug frequency, which may lead to poor patient compliance and serious complications due to drug overdose. Therefore, it is of great interest to develop controlled-release drug delivery systems for local anesthetics, enabling slow and controlled drug release to prolong the analgesic effect and minimize systemic toxicity. In this study, we utilized an electrospinning technique to fabricate nonwoven poly(caprolactone) (PCL) fibrous membranes loaded with Ropivacaine and performed proof-of-principle experiments on both in vitro drug release tests and in vivo animal tests, to further prolong the analgesic effect of Ropivacaine and improve postoperative local pain management and chronic pain treatment. Material characterization and in vitro drug release studies confirmed the feasibility of the Ropivacaine-loaded PCL fibrous membranes for sustained release. The drug loading content and drug loading efficiency of Ropivacaine-loaded fibrous membrane are 8.7 ± 0.3 wt% and 96 ± 3 wt%, respectively. Evaluation in an animal model demonstrated prolonged anesthesia effects along with excellent biocompatibility and stability. At 72 h, the cumulative release accounted for approximately 50% of the drug loading content. This study offers novel approaches and strategies for clinical postoperative pain management and chronic pain treatment, while providing new insights and directions for the design of local anesthetic controlled-release delivery systems.

Construction of Electrostatic Spinning Membranes Based on Conjugated Hemicyanine Derivatives for Photodynamic Antibacterial Application

The preparation of efficient antibacterial membrane materials is one of the important strategies to fight against bacterial infection and alleviate drug resistance. Herein, hemicyanine derivatives with different chain lengths (C3, C6, and C10) that exhibit excellent photodynamic antibacterial activity were doped into spinnable polyvinyl alcohol solution (PVA, 8%) to obtain composite fiber membrane Cn/PVA (C3/PVA, C6/PVA, and C10/PVA) by a simple "one-pot" method using electrospinning technology. The antibacterial nanofiber membrane has a dense fiber structure which has a good interception effect, high thermal stability, and great biocompatibility. Importantly, Cn/PVA nanofibers could efficiently sensitize oxygen to generate reactive oxygen species (ROS), leading to high photokilling efficacy against drug-resistant bacteria. The variation of structure for hemicyanines causes the difference of Cn/PVA nanofibers in the effects of antibacterial performance, and it is found that C3/PVA and C10/PVA with three and ten carbons in the alkyl chain could kill more than 97% of ampicillin-resistant E. coli, which is much better than that of C6/PVA. Moreover, C3/PVA and C10/PVA exhibited killing efficiencies of 98.6 and 90.6% against MRSA, respectively. The construction of Cn/PVA composite fibers provides research ideas for the development of structure-dependent antimicrobial surface materials and is expected to be applied as superficial medical antibacterial protection materials.

Design and Fabrication of Electrospun PLA-Based Silica-Modified Composite Nanofibers with Antibacterial Properties for Perspective Wound Treatment

The aim of this study was to develop a novel amikacin (AMI) delivery system with prolonged release based on composite electrospun nanofibers of PLA supplemented with AMI-loaded Si nanoparticles of different morphology. The resultant materials were characterized in terms of their physical properties (scanning electron microscopy, Brunauer-Emmett-Teller analysis, thermogravimetric analysis, water contact angle). High-Performance Liquid Chromatography was used to determine the AMI content in the liquid fractions obtained from the release study. The results show that nanofibers of fumed silica exhibited an aggregated, highly porous structure, whereas nanofibers of mesoporous silica had a spherical morphology. Both silica nanoparticles had a significant effect on the hydrophilic properties of PLA nanofiber surfaces. The liquid fractions were investigated to gauge the encapsulation efficiency (EE) and loading efficiency (LE) of AMI, demonstrating 66% EE and 52% LE for nanofibers of fumed silica compared to nanofibers of mesoporous silica nanoparticles (52% EE and 12.7% LE). The antibacterial activity of the AMI-loaded nanofibers was determined by the Kirby-Bauer Method. These results demonstrated that the PLA-based silica nanofibers effectively enhanced the antibacterial properties against the Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Klebsiella pneumoniae.

Preparation of pH-responsive magnetic nanocomposite hydrogels based on k-carrageenan/chitosan/silver nanoparticles: Antibacterial carrier for potential targeted anticancer drug delivery

This study reports the development of new pH-responsive drug delivery systems that are important for the treatment of cancer. The Mentha plant extract was obtained and then used for the biosynthesis of magnetic Ag bio nanoparticles (M-Ag bio-NPs). They were added in the formulation of hybrid hydrogel of k-carrageenan (k-Cr) and chitosan (CS) toward the synthesis of magnetic nanocomposite hydrogels. Their chemical structure and morphology were characterized by different analyses. Doxorubicin (DOX) was used as a model anticancer drug to study the targeted drug release behavior of the synthesized nanocomposite hydrogels (loading capacity: about 98 %). In vitro drug release studies showed that the release profile was noticeably controlled in a pH-dependent manner (higher drug release at pH 5). The antibacterial assessment confirmed the high antibacterial activity for the synthesized hydrogel against S. aureus (MIC values 39.06 μg/mL) and E. coli (MIC values > 19.53). In-vitro cytotoxicity results (MTT assay) demonstrated good biocompatibility (higher than 88 %) for the blank nanocomposite hydrogels, while DOX-loaded nanocomposite hydrogels showed high toxicity (about 22 % in the concentration of 20 μg/mL) against HeLa cells. The results showed that the present nanocomposite hydrogels can be suggested for potential application as an antibacterial and anticancer carrier.

Stimuli-responsive electrospun nanofibers for drug delivery, cancer therapy, wound dressing, and tissue engineering

The stimuli-responsive nanofibers prepared by electrospinning have become an ideal stimuli-responsive material due to their large specific surface area and porosity, which can respond extremely quickly to external environmental incitement. As an intelligent drug delivery platform, stimuli-responsive nanofibers can efficiently load drugs and then be stimulated by specific conditions (light, temperature, magnetic field, ultrasound, pH or ROS, etc.) to achieve slow, on-demand or targeted release, showing great potential in areas such as drug delivery, tumor therapy, wound dressing, and tissue engineering. Therefore, this paper reviews the recent trends of stimuli-responsive electrospun nanofibers as intelligent drug delivery platforms in the field of biomedicine.

Capsaicin-loaded alginate nanoparticles embedded polycaprolactone-chitosan nanofibers as a controlled drug delivery nanoplatform for anticancer activity

Nanocarrier-based drug delivery systems have been designed into various structures that can effectively prevent cancer progression and improve the therapeutic cancer index. However, most of these delivery systems are designed to be simple nanostructures with several limitations, including low stability and burst drug release features. A nano-in-nano delivery technique is explored to address the aforementioned concerns. Accordingly, this study investigated the release behavior of a novel nanoparticles-in-nanofibers delivery system composed of capsaicin-loaded alginate nanoparticles embedded in polycaprolactone-chitosan nanofiber mats. First, alginate nanoparticles were prepared with different concentrations of cationic gemini surfactant and using nanoemulsion templates. The optimized formulation of alginate nanoparticles was utilized for loading capsaicin and exhibited a diameter of 19.42 ± 1.8 nm and encapsulation efficiency of 98.7 % ± 0.6 %. Likewise, blend polycaprolactone-chitosan nanofibers were prepared with different blend ratios of their solutions (i.e., 100:0, 80:20, 60:40) by electrospinning method. After the characterization of electrospun mats, the optimal nanofibers were employed for embedding capsaicin-loaded alginate nanoparticles. Our findings revealed that embedding capsaicin-loaded alginate nanoparticles in polycaprolactone-chitosan nanofibers, prolonged capsaicin release from 120 h to more than 500 h. Furthermore, the results of in vitro analysis demonstrated that the designed nanoplatform could effectively inhibit the proliferation of MCF-7 human breast cells while being nontoxic to human dermal fibroblasts (HDF). Collectively, the prepared nanocomposite drug delivery platform might be promising for the long-term and controlled release of capsaicin for the prevention and treatment of cancer.

Electrospun Hyaluronan Nanofiber Membrane Immobilizing Aromatic Doxorubicin as Therapeutic and Regenerative Biomaterial

Lesioned tissue requires synchronous control of disease and regeneration progression after surgery. It is necessary to develop therapeutic and regenerative scaffolds. Here, hyaluronic acid (HA) was esterified with benzyl groups to prepare hyaluronic acid derivative (HA-Bn) nanofibers via electrospinning. Electrospun membranes with average fiber diameters of 407.64 ± 124.8 nm (H400), 642.3 ± 228.76 nm (H600), and 841.09 ± 236.86 nm (H800) were obtained by adjusting the spinning parameters. These fibrous membranes had good biocompatibility, among which the H400 group could promote the proliferation and spread of L929 cells. Using the postoperative treatment of malignant skin melanoma as an example, the anticancer drug doxorubicin (DOX) was encapsulated in nanofibers via hybrid electrospinning. The UV spectroscopy of DOX-loaded nanofibers (HA-DOX) revealed that DOX was successfully encapsulated, and there was a π-π interaction between aromatic DOX and HA-Bn. The drug release profile confirmed the sustained release of about 90%, achieved within 7 days. In vitro cell experiments proved that the HA-DOX nanofiber had a considerable inhibitory effect on B16F10 cells. Therefore, the HA-Bn electrospun membrane could facilitate the potential regeneration of injured skin tissues and be incorporated with drugs to achieve therapeutic effects, offering a powerful approach to developing therapeutic and regenerative biomaterial.

A SWOT analysis of nano co-crystals in drug delivery: present outlook and future perspectives

The formulation of poorly soluble drugs is an intractable challenge in the field of drug design, development and delivery. This is particularly problematic for molecules that exhibit poor solubility in both organic and aqueous media. Usually, this is difficult to resolve using conventional formulation strategies and has resulted in many potential drug candidates not progressing beyond early stage development. Furthermore, some drug candidates are abandoned due to toxicity or have an undesirable biopharmaceutical profile. In many instances drug candidates do not exhibit desirable processing characteristics to be manufactured at scale. Nanocrystals and co-crystals, are progressive approaches in crystal engineering that can solve some of these limitations. While these techniques are relatively facile, they also require optimisation. Combining crystallography with nanoscience can yield nano co-crystals that feature the benefits of both fields, resulting in additive or synergistic effects to drug discovery and development. Nano co-crystals as drug delivery systems can potentially improve drug bioavailability and reduce the side-effects and pill burden of many drug candidates that require chronic dosing as part of treatment regimens. In addition, nano co-crystals are carrier-free colloidal drug delivery systems with particle sizes ranging between 100 and 1000 nm comprising a drug molecule, a co-former and a viable drug delivery strategy for poorly soluble drugs. They are simple to prepare and have broad applicability. In this article, the strengths, weaknesses, opportunities and threats to the use of nano co-crystals are reviewed and a concise incursion into the salient aspects of nano co-crystals is undertaken.

Electrospun fibers with blank surface and inner drug gradient for improving sustained release

New engineering methods and advanced strategies are highly desired for creating novel drug sustained release nanomaterials. In this study, a trilayer concentric spinneret was explored to implement several multifluid electrospinning processes. A trilayer core-shell nanofiber was successfully fabricated, which comprise a drug-free polymeric coating and an inner drug gradient distribution, and then compared with bilayer core-shell and monolithic medicated nanofibers. All the electrospun nanofibers similarly consisted of two components (guest drug acetaminophen and host polymer cellulose acetate) and presented a linear morphology. Due to the secondary interactions within nanofibers, loaded drug with amorphous state was detected, as demonstrated by SEM, DSC, XRD, and FTIR determinations. In vitro and in vivo gavage treatments to rats tests were carried out, the trilayer nanofiber with an elaborate structure design were demonstrated to provide better drug sustained release profile than the bilayer core-shell nanofibers in term of initial burst release, later tail-off release and long sustained release time period. The synergistic mechanism for improving the drug sustained release behaviors is disclosed. By breaking the traditional concepts about the implementation of multifluid electrospinning and the strategy of combining surface properties and inner structural characteristics, the present protocols open a new way for developing material processing methods and generating novel functional nanomaterials.

Formation of Hydrophilic Nanofibers from Nanostructural Design in the Co-Encapsulation of Celecoxib through Electrospinning

This study presents a method for a one-step co-encapsulation of PLGA nanoparticles in hydrophilic nanofibers. The aim is to effectively deliver the drug to the lesion site and achieve a longer release time. The celecoxib nanofiber membrane (Cel-NPs-NFs) was prepared by emulsion solvent evaporation and electrospinning with celecoxib as a model drug. By this method, nanodroplets of celecoxib PLGA are entrapped within polymer nanofibers during an electrospinning process. Moreover, Cel-NPs-NFs exhibited good mechanical strength and hydrophilicity, with a cumulative release of 67.74% for seven days, and the cell uptake at 0.5 h was 2.7 times higher than that of pure nanoparticles. Furthermore, pathological sections of the joint exhibited an apparent therapeutic effect on rat OA, and the drug was delivered effectively. According to the results, this solid matrix containing nanodroplets or nanoparticles could use hydrophilic materials as carriers to prolong drug release time.

Current Advances in Lipid Nanosystems Intended for Topical and Transdermal Drug Delivery Applications

Skin delivery is an exciting and challenging field. It is a promising approach for effective drug delivery due to its ease of administration, ease of handling, high flexibility, controlled release, prolonged therapeutic effect, adaptability, and many other advantages. The main associated challenge, however, is low skin permeability. The skin is a healthy barrier that serves as the body's primary defence mechanism against foreign particles. New advances in skin delivery (both topical and transdermal) depend on overcoming the challenges associated with drug molecule permeation and skin irritation. These limitations can be overcome by employing new approaches such as lipid nanosystems. Due to their advantages (such as easy scaling, low cost, and remarkable stability) these systems have attracted interest from the scientific community. However, for a successful formulation, several factors including particle size, surface charge, components, etc. have to be understood and controlled. This review provided a brief overview of the structure of the skin as well as the different pathways of nanoparticle penetration. In addition, the main factors influencing the penetration of nanoparticles have been highlighted. Applications of lipid nanosystems for dermal and transdermal delivery, as well as regulatory aspects, were critically discussed.

Hybrid Systems of Nanofibers and Polymeric Nanoparticles for Biological Application and Delivery Systems

Nanomedicine is a new discipline resulting from the combination of nanotechnology and biomedicine. Nanomedicine has contributed to the development of new and improved treatments, diagnoses, and therapies. In this field, nanoparticles have notable importance due to their unique properties and characteristics, which are useful in different applications, including tissue engineering, biomarkers, and drug delivery systems. Electrospinning is a versatile technique used to produce fibrous mats. The high surface area of the electrospun mats makes them suitable for applications in fields using nanoparticles. Electrospun mats are used for tissue engineering, wound dressing, water-treatment filters, biosensors, nanocomposites, medical implants, protective clothing materials, cosmetics, and drug delivery systems. The combination of nanoparticles with nanofibers creates hybrid systems that acquire properties that differ from their components' characteristics. By utilizing nanoparticles and nanofibers composed of dissimilar polymers, the two synergize to improve the overall performance of electrospinning mats and nanoparticles. This review summarizes the hybrid systems of polymeric nanoparticles and polymeric nanofibers, critically analyzing how the combination improves the properties of the materials and contributes to the reduction of some disadvantages found in nanometric devices and systems.

Antibacterial and Antifouling Efficiency of Essential Oils-Loaded Electrospun Polyvinylidene Difluoride Membranes

Nanofibers have become a promising material in many industries in recent years, mainly due to their various properties. The only disadvantage of nanofibers as a potential filtration membrane is their short life due to clogging by bacteria in water treatment. The enrichment of nanofibers with active molecules could prevent these negative effects, represented by essential oils components such as Thymol, Eugenol, Linalool, Cinnamaldehyde and Carvacrol. Our study deals with the preparation of electrospun polyvinylidene difluoride (PVDF)-based nanofibers with incorporated essential oils, their characterization, testing their antibacterial properties and the evaluation of biofilm formation on the membrane surface. The study of the nanofibers' morphology points to the nanofibers' diverse fiber diameters ranging from 570 to 900 nm. Besides that, the nanofibers were detected as hydrophobic material with wettability over 130°. The satisfactory results of PVDF membranes were observed in nanofibers enriched with Thymol and Eugenol that showed their antifouling activity against the tested bacteria Escherichia coli ATCC 25922 and Staphylococcus aureus ATCC 25923. Therefore, these PVDF membranes could find potential applications as filtration membranes in healthcare or the environment.

Antimicrobial Activity of Blow Spun PLA/Gelatin Nanofibers Containing Green Synthesized Silver Nanoparticles against Wound Infection-Causing Bacteria

One of the main challenges in wound healing is the wound infection due to various causes, of which moisture is the most important reason. Owing to this fact, wound dressings that can collect wound moisture in addition to showing antibacterial properties have provided an important basis for wound healing research. In this study, gelatin and poly lactic acid (PLA) polymers were used in a wound dressing textile to provide gelation and structure strength properties, respectively. Meanwhile, silver nanoparticles (SNPs) synthesized through the green method were integrated into these fibers to provide the formed textile with antibacterial properties. Nanoparticles were made using donkey dung extract, and nanofibers were produced by the solution blow spinning method which has high production efficiency and low energy consumption among spinning methods. The produced nanoparticles were characterized and evaluated by UV-Vis, DLS, XRD, and FTIR methods, and the production of silver nanoparticles that were coated with metabolites in the extract was proven. In addition, the morphology and diameter of the resulted fibers and presence of nanoparticles were confirmed by the SEM method. The size and size distribution of the synthesized fibers were determined through analyzing SEM results. Gelatin nanofibers demonstrated a mean size of 743 nm before and 773 nm after nanoparticle coating. PLA nanofibers demonstrated a mean size of 57 nm before and 182 nm after nanoparticle coating. Finally, 335 nm was the mean diameter size of gelatin/PLA/SNPs nanofibers. Also, the textiles synthesized by PLA and gelatin which contained silver nanoparticles showed higher antibacterial activity against both gram-positive and gram-negative species compared to PLA and gelatin tissues without nanoparticles. Cytotoxicity test on L929 cells showed that silver nanoparticles incorporated textiles of PLA and gelatin show a very low level and non-significant toxicity compared to the free particles.

Nanofibrous Wound Healing Nanocomposite Based on Alginate Scaffold: In Vitro and In Vivo Study

The combination of nanofibers with 3D scaffolds has shown promising results as the wound healing/dressing/care biomaterials. The present study aimed to fabricate and optimized alginate hydrogel composited by Lignin-derived carbon nanofibers (CNFs). The nanofibers were obtained from electrospun Lignin nanofibers as the precursor through two steps heat treatments. The synthesized nanofibers blended with an alginate polymer solution with different concentrations (1, 5, and 10 wt.%) and cross-linked using CaCl2 through the physical cross-linking. The findings illustrated that the prepared Lignin and CNFs have acceptable diameter. The composited Alginate hydrogels possessed a porous internal-structure with interconnected architecture. The fabricated hydrogel exhibited proper porosity and swelling behavior beneficial for wound healing application. The In Vitro experiments revealed that the hydrogel were red blood cell (RBC)-compatible, cytocompatible, and induced proliferative effects on cells. The animal experiments indicated that the application of the hydrogel promoted the process of wound healing. These observations implied that the prepared hydrogel nanocomposites exhibited promising properties and can be considered as wound healing nanobiomaterials.