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This study deals with poly(lactic acid) (PLA), poly([epsilon]-caprolactone) (PCL), and their blend electrospun nanofibers (ESNF) as novel systems for the release of levetiracetam (LEV). Scanning electron microscopy demonstrated that the morphology of all samples is smooth and beads-free. In addition, with increasing LEV content, the average diameters of PLA, PCL, and PCL/PLA ESNF enhanced by almost 69%, 41%, and 14%, respectively. FTIR spectroscopy was utilized to confirm the structure of polymer and drug, polymer-drug interaction, and the observation of functional groups. The pore percentage was also diminished by adding LEV. The results of x-ray diffraction revealed that the crystallinity decreased from 18.2%, 40.1%, and 21.5% for PLA, PCL, and PLA/PCL ESNF, respectively, to 15%, 31.2%, and 13.6% for the samples containing 18wt% LEV. In addition, PLA ESNF containing 10 and 18wt% LEV demonstrated a steady uptrend for drug release, while PCL and PLA/PCL ESNF containing 10 and 18wt% LEV initially indicated an abrupt increase in drug release and then became steady. Moreover, drug release kinetics were evaluated using different models such as zero order, first order, Higuchi, and Korsmeyer-Peppas models and the best model for predicting the drug release behavior was selected. KEYWORDS drug release, electrospun nanofibers, levetiracetam, poly ([epsilon]-caprolactone), poly(lactic acid), 1 | INTRODUCTION Polymers exhibit exceptional diversity, versatility, and practicality, which is why they have attracted so much attention these days. [1-6] Polymer fibers are significant materials for medical applications [...]

Nanocomposites based on thermoplastic polyurethane (TPU) and poly lactic acid (PLA) with different weight ratios of 10:90 and 30:70 were prepared by solution method. Hydroxyapatite nanoparticles (n-HA) were used to enhance the physical and mechanical properties of the alloys. To prepare the nanocomposites, the percentages of n-HA varied between 1% and 5%. Different tests were used to investigate the properties of these nanocomposites. Scanning electron microscopy (SEM) analysis, which was used to study the morphology of the blends, showed that there were rough morphologies in between materials, and the results of the mapping test showed that the dispersion of nanoparticles in the polymer matrix was almost good. TGA thermal degradation test showed that the presence of TPU to some extent can affect the thermal stability properties, and with the increase in this material, the thermal properties are strengthened. The crystalline behavior of the samples showed that the presence of TPU and n-HA nanoparticles had negative effects on the crystalline properties. The study of viscoelastic behaviors showed that the presence of TPU enhances the viscous behavior in the sample and decreases the glass transition temperature, while the presence of nanoparticles increases the elastic properties and glass transition temperature. Tensile test showed that the presence of n-HA has a greater effect on the mechanical properties. Dynamic contact angle analysis using water and dimethylformamide (DMF) solvent showed that the existing TPU and n-HA led to major changes in the interaction surface of scaffolds. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide analysis showed that increasing the amounts of TPU and HA increases cell viability. SEM cell interactions analysis showed that the surfaces of PLA90TPU10H5 and PLA70TPU30H5 samples are very good for the preparation of bone tissue scaffolds. Our findings indicated that the addition of n-HA into PLA/TPU blends could impart new features to the PLA matrix as a promising candidate for bone, cartilage, and tendon tissue engineering.

In this study, semiconductive poly (lactic acid) (PLA)/carbon nanotube (CNT) nanocomposites have been simultaneously subjected to melt-compounding and foaming using a continuous and single-step extrusion foaming process. The extrusion foaming process with the ability to be developed on an industrial scale is a complex process for a biopolymer in the presence of nanoparticles, chemical foaming agent, and chain extender, and to control it, knowledge about the phenomena occurring during the process and the structural properties of the foam is required. Although the extrusion foaming of PLA has been studied before, the simultaneous effects of chain extender content and nanoparticle loading on the microstructure and phenomena during the PLA extrusion foaming process have not been thoroughly investigated. The results of this study show that the two investigated variables have a strong interaction with each other. Increasing the chain extender content has led to a change in the rheological properties of the melt, as a result, it has been significantly effective in the nanoparticle dispersion state. Besides, the loading of nanoparticles has a powerful effect on the intensity of the chain extension reaction of PLA chains by the chain extender additive. The lightest extruded foams (with a void fraction of 0.52) with the highest cell density (5 × 106 cells/cm3), the smallest cell size (about 50 and 200 µm for number- and volume-average cell diameters), and the most uniform cell size distribution have been obtained in the middle values of the chain extender content (5 phr) and the lowest values of the nanoparticle loading (0.25 phr). [ABSTRACT FROM AUTHOR]

The importance of biopolymer-based nanocomposites in food packaging is growing significantly. Therefore, in the present study, we aim to examine the impact of zinc oxide (ZnO), polyhedral oligomeric silsesquioxanes (POSS), and, for the first time, their hybrid on polycaprolactone (PCL) nanocomposites. For this matter, different concentrations of 1, 3, and 5 wt% of each nanoparticle and the hybrid were incorporated into the PCL nanocomposites via the solution casting method. Their chemical structures and interactions, crystalline structures, and morphology were investigated by FT-IR, WAXD, and SEM. Moreover, it was observed through contact angle and surface free energy experiments that an increase in the nanoparticle concentration corresponded to an increase in the contact angle values. The incorporation of hybrid POSS and ZnO equilibrated well between Young's modulus, tensile strength, and elongation of the samples in their single status. Accordingly, the addition of the hybrid nanoparticles up to 3 wt% significantly increased the modulus and yield strength of PCL nanocomposites without any significant sacrifice in toughness. Also, PPZ3 (containing an optimal 3%wt. of hybrid nanoparticles) demonstrated the lowest permeability against both water vapor and O2 gas, exhibiting reductions of approximately 30 and 55% when compared to pristine PCL. Finally, the antibacterial properties of the nanocomposite films were investigated for S. aureus and E. coli bacteria and revealed. In addition to the antibacterial properties of ZnO and POSS nanoparticles, increasing the concentration of hybrid nanoparticles up to 5 wt% expanded S. aureus's inhibitory zone. The balanced mechanical, and barrier characteristics, enhanced morphologies, and antibacterial effects of the novel hybrid nanocomposites present novel opportunities in the field of food packaging. [ABSTRACT FROM AUTHOR]

This review provides a comprehensive overview of the emerging applications of stimuli‐responsive hydrogels in 3D printing, emphasizing their transformative potential in creating adaptive and multifunctional structures. Stimuli‐responsive hydrogels, including magneto‐, thermo‐, pH‐, moisture‐, solvent‐, and photo‐responsive varieties, have gained significant attention due to their ability to undergo dynamic changes in response to specific environmental stimuli. The review begins by exploring the fundamental characteristics and fabrication methods of hydrogels used in additive manufacturing, highlighting their exceptional adaptability and programmability. It then delves into various applications across diverse fields, including soft robotics, tissue engineering, drug delivery systems, wearable electronics, food technology, electromagnetic interference shielding, and anti‐counterfeiting technologies. By integrating the latest advancements in 3D printing techniques, this review aims to offer insights into how stimuli‐responsive hydrogels are enabling the development of innovative, intelligent, and environmentally responsive systems. The future perspectives section discusses challenges and opportunities for advancing the use of hydrogels in 3D printing, suggesting directions for future research that could push the boundaries of functional materials and programmable structures. [ABSTRACT FROM AUTHOR]

This review aims to provide a comprehensive analysis of recent advancements in smart microneedles (MNs) within the biomedical field, focusing on the integration of stimuli‐responsive polymers for enhanced therapeutic and diagnostic applications. Conventional drug delivery and diagnostic methods are known to face limitations in precision, safety, and patient compliance, which can be addressed by the innovative features of smart MNs. Through the use of various stimuli‐responsive polymers, these MNs have been designed to react to environmental or physiological cues, allowing for on‐demand drug release, biomarker sensing, and localized therapeutic interventions. Fundamental materials used in the fabrication of these MNs, including metals, polymers, and composite hydrogels, are reviewed, and different categories of stimuli‐responsiveness, such as photo, electro, thermal, mechanical, and biochemical, are explored. Application‐specific designs of MNs in areas such as drug delivery, cancer therapy, diabetes management, and skin disease treatments are also examined. Through this discussion, it is highlighted that smart MNs are poised to play a significant role in advancing personalized and noninvasive medical treatments. [ABSTRACT FROM AUTHOR]

MXene‐based hydrogels represent a significant advancement in biomedical material science, leveraging the unique properties of 2D MXenes and the versatile functionality of hydrogels. This review discusses recent developments in the integration of MXenes into hydrogel matrices, focusing on their biomedical applications such as wound healing, drug delivery, antimicrobial activity, tissue engineering, and biosensing. MXenes, due to their remarkable electrical conductivity, mechanical robustness, and tunable surface chemistry, enhance the mechanical properties, conductivity, and responsiveness of hydrogels to environmental stimuli. Specifically, MXene‐based hydrogels have shown great promise in accelerating wound healing through photothermal effects, delivering drugs in a controlled manner, and serving as antibacterial agents. Their integration into hydrogels also enables applications in targeted cancer therapies, including photothermal and chemodynamic therapies, facilitated by their high conductivity and tunable properties. Despite the promising progress, challenges such as ensuring biocompatibility and optimizing the synthesis for large‐scale production remain. This review aims to provide a comprehensive overview of the current state of MXene‐based hydrogels in biomedical applications, highlighting the ongoing advancements and potential future directions for these multifunctional materials. [ABSTRACT FROM AUTHOR]

The development of effective wound dressings is critical for enhancing patient outcomes in both acute and chronic wound care scenarios. In this research, electrospun nanofibrous scaffolds were fabricated from poly(ε-caprolactone) (PCL), enhanced with curcumin and reduced graphene oxide (RGO) to optimize their biomedical applications, particularly in wound healing. The resulting scaffolds were rigorously characterized through scanning electron microscopy, contact angle measurements, water uptake capacity, and water vapor transmission rate assays. The biocompatibility of these novel nanofibers was affirmed through MTT assays. Antibacterial tests confirmed the scaffolds' ability to inhibit both Gram-negative and Gram-positive bacteria, with inhibition zones measuring up to 9.9 mm for S. aureus and 9.2 mm for E. coli. Additionally, scaffolds containing curcumin exhibited significant antioxidant activity, achieving up to 40% radical scavenging efficiency. The study further revealed the scaffolds' capability for sustained drug release, with an initial burst release within the first 12 hours followed by a gradual release over 168 hours. Overall, the PCL-curcumin-RGO electrospun mats demonstrated considerable potential for biomedical applications, notably in the field of wound dressings, due to their enhanced antibacterial, antioxidant, and biocompatible properties. [ABSTRACT FROM AUTHOR]

Diabetes mellitus is a chronic condition characterized by impaired insulin production or utilization, leading to serious complications such as diabetic foot ulcers (DFUs). DFUs are chronic wounds with high levels of inflammatory cytokines, arterial occlusion, and persistent infection, often resulting in significant morbidity. Traditional treatment methods, including debridement, offloading, and infection control, have shown limited success, prompting the exploration of novel therapeutic strategies. Insulin, known for its role in glucose metabolism, also possesses wound‐healing properties by promoting cell proliferation, protein synthesis, and modulating inflammation. However, systemic insulin administration is not ideal due to hypoglycemia risks and difficulties in achieving therapeutic concentrations at wound sites. This review focuses on advanced drug delivery systems for the topical application of insulin in wound dressings. Various delivery platforms, including hydrogels, nanoparticles, liposomes, and microemulsions have been developed to optimize insulin bioavailability, protect it from degradation, and ensure controlled release. These systems aim to enhance the management of diabetic wounds by addressing the multifactorial nature of wound healing complications in diabetic patients. The review provides a comprehensive overview of current advancements, evaluates the efficacy of these systems in preclinical and clinical studies, and discusses the challenges and future perspectives in this field. By highlighting the potential of these innovative approaches, this review underscores the promise of advanced topical insulin delivery systems in improving diabetic wound management and patient outcomes. [ABSTRACT FROM AUTHOR]

The effect of incorporating different percentages of hydrophobic and hydrophilic nanosilica (HPB and HPL NS) particles and chain extender (CE) on the mechanical behavior of poly(lactic acid)/poly(butylene adipate‐co‐terephthalate) (PLA/PBAT) blends was evaluated. The mechanical behavior of the samples was explained using different theoretical models. Microscopic studies showed that adding both types of NS particles and CE led to more uneven surfaces for blends. Also, no obvious aggregations were observed in both blend nanocomposites, and both kinds of NS particles were mainly present in the PBAT phase. Except for the blend containing 1 phr HPB NS particles, which revealed a continuous morphology, all the PLA/PBAT blends containing both types of NS particles indicated a droplet‐matrix morphology. The more the NS content, the more uniform the PBAT distribution. Adding CE in the blends improved Young's modulus, yield strength, and elongation‐at‐break to a particular loading of CE (2 phr), while these properties were diminished after introducing more CE. Also, the most improvements in the yield strength (45%) and Young's modulus (35%) were seen for the PLA/PBAT (75/25 w/w) containing 2 phr CE and 5 phr HPL NS particles. Besides, a good agreement was observed for experimental values and theoretical models for all samples. [ABSTRACT FROM AUTHOR]

Aim: The study aims to improve glioblastoma multiforme (GBM) treatment by combining temozolomide (TMZ) and quercetin (Qct), using folic acid (FA)-conjugated exosomes to overcome TMZ resistance and enhance blood–brain barrier (BBB) penetration. Methods: Exosomes were isolated and after characterizing and modifying their surfaces with FA, drug loading of TMZ and Qct into exosomes was done. In vitro assays, including cell viability tests, RT-PCR, Western-blotting and flow-cytometry, were performed using U87MG and U251MG GBM cell lines. In vivo analysis included administering exosome-drug formulations to glioblastoma-bearing Wistar rats, monitored through optical imaging and PET scans, followed by post-mortem immunohistochemistry and histological examination. Results: The results showed successful exosome isolation and FA conjugation, with drug release studies indicating accelerated release of TMZ and Qct in acidic conditions, enhancing cytotoxicity. Immunofluorescence indicated greater exosome uptake in GBM cells due to FA conjugation. Cell viability assays demonstrated increased toxicity of the combination therapy, correlating with elevated apoptosis. In vivo studies revealed significant tumor size reduction, alongside increased apoptosis and reduced angiogenesis, particularly in the TMZ-Qct-Exo-FA group. Conclusion: FA-conjugated exosomes loaded with TMZ and Qct represent a promising strategy to enhance GBM treatment efficacy by improving drug delivery, apoptosis induction and inhibiting the PI3K/Akt/mTOR pathway. Graphical Abstract Schematic illustration of exosome isolation and conjugation followed by loading with temozolomide (TMZ) and Quercetin (Qct) for glioblastoma therapy. (A) Process of isolating exosomes and conjugating them with folic acid loaded with TMZ and Qct (B) Function of exosomes conjugated with folic acid in a rat model of glioblastoma (C) Mechanism of how exosomes bearing TMZ and Qct work inside the glioblastoma cell line. Article highlights The study emphasizes the successful use of exosome encapsulation to enhance the delivery of temozolomide (TMZ) and quercetin (Qct) across the blood–brain barrier (BBB), improving drug stability for glioblastoma multiforme (GBM) therapy. Encapsulating TMZ and Qct within exosomes (TMZ-Qct-Exo) showed significantly greater potential in reducing GBM cell viability compared with their unencapsulated counterparts, suggesting an effective approach against TMZ resistance. The introduction of folic acid-conjugated exosomes (TMZ-Qct-Exo-FA) enhanced the targeting of GBM cells, leading to better cellular uptake and improved therapeutic outcomes marked by greater apoptosis and increased caspase-3 levels. The combined treatment effectively inhibited the PI3K/Akt/mTOR signaling pathway, vital for tumor growth and survival, thereby boosting the anti-tumor effects of the TMZ-Qct-Exo-FA treatment. In vivo studies demonstrated that the TMZ-Qct-Exo-FA formulation resulted in superior tumor targeting, significantly reduced tumor size and higher levels of apoptotic markers compared with alternative treatment methods. The findings highlight that exosome-mediated drug delivery could serve as a promising strategy to circumvent resistance mechanisms commonly associated with TMZ in GBM treatment. The research indicates that combining exosome technology with conventional chemotherapy could pave the way for new therapeutic modalities in the treatment of aggressive brain tumors like GBM. The use of folic acid as a targeting moiety suggests an innovative approach to enhance specificity in drug delivery systems directed at tumor cells. These results underscore the need for further clinical studies to explore the full potential of exosome-mediated delivery systems in enhancing the effectiveness of existing cancer therapies. [ABSTRACT FROM AUTHOR]

The purpose of this study was to synthesize and characterize the therapeutic effect of paclitaxel‐loaded polyethylene glycol modified polyethylene imine‐coated iron oxide nanoparticles on cervical cancer cell line (HeLa cell). The physiochemical characteristics of nanocarriers were confirmed by using several methods including X‐ray diffraction (XRD), Thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FT‐IR), Vibrating sample magnetometer (VSM), Dynamic light scattering (DLS), and Transmission electron microscopy (TEM). The results showed the magnetic nanoparticles with size of 35 nm and excellent magnetic properties could load paclitaxel with capacity (16%) and encapsulation efficiency (80%) that has revealed pH‐dependent release behavior. The anticancer effects of nanoparticles were investigated using MTT assay. In comparison to free drug, paclitaxel‐loaded magnetic nanocarrier revealed more cytotoxicity against HeLa cell line and also resulted in an increased rate of apoptotic cancer cells, assessed by flow cytometry analysis. Furthermore, the developed magnetic nanocarrier showed suitable hemocompatibility which can be used in clinical applications. [ABSTRACT FROM AUTHOR]