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This research investigates the rheological behavior of the Poloxamer–chitosan thermogel system for the release of doxorubicin, which is a chemotherapy agent. To design the experiment, the response surface method was used to optimize the formula and investigate the mutual effects of the variables on the rheological properties of the system. In this experimental design, Poloxamer as a thermogel matrix (15–20%) and chitosan biopolymer as an additive (0.1–0.3%) were used and the pH of the test environment was determined in the range of 2.0–7.5. The results showed that the rheological behavior of the Poloxamer–chitosan combination has the best fit according to the Herschel–Bulkley model with a correlation coefficient of 100%. Also, adding chitosan to Poloxamer decreased the gelation temperature and gelation time. The results showed that the concentration of Poloxamer and chitosan as well as system temperature have a significant effect on the rheological behavior of thermogel. The optimized formula showed favorable rheological properties including high viscosity and appropriate degradation rate. The study showed the sustained release of the drug in the in vitro environment of the thermogel system during 144 h. The kinetics of the drug's release were also studied based on zero-order, first-order, Higuchi, and Korsmeyer–Peppas models. It was found that the Higuchi (R2 = 0.9888) and Korsmeyer–Peppas (R2 = 0.9851) models are the best models for the prediction of release kinetics of doxorubicin. Therefore, the design of the Poloxamer–chitosan thermogel system has the potential to be used as an in situ drug delivery system for doxorubicin. [ABSTRACT FROM AUTHOR]

Severe cutaneous injuries may not heal spontaneously and may necessitate the use of supplementary therapeutic methods. Electrospun nanofibers possess high porosity and specific surface area, which provide the necessary microenvironment for wound healing. Here in, the nanofibers of Soluplus-soy protein isolate (Sol-SPI) containing mupirocin (Mp) were fabricated via electrospinning for wound treatment. The fabricated nanofibers exhibited water absorption capacities of about 300.83 ± 29.72% and water vapor permeability values of about 821.8 ± 49.12 g/m2 day. The Sol/SPI/Mp nanofibers showed an in vitro degradability of 33.73 ± 3.55% after 5 days. The ultimate tensile strength, elastic modulus, and elongation of the Sol/SPI/Mp nanofibers were measured as 3.61 ± 0.29 MPa, 39.15 ± 5.08 MPa, and 59.11 ± 1.94%, respectively. Additionally, 85.90 ± 6.02% of Mp loaded in the nanofibers was released in 5 days in vitro, and by applying the Mp-loaded nanofibers, 93.06 ± 5.40% and 90.40 ± 5.66% of S. aureus and E. coli bacteria were killed, respectively. Human keratinocyte cells (HaCat) demonstrated notable biocompatibility with the prepared nanofibers. Furthermore, compare to other groups, Sol-SPI-Mp nanofibers caused the fastest re-epithelialization and wound healing in a rat model. The findings of this study present a novel nanofiber-based wound dressing that accelerates the healing of severe skin wounds with the risk of infection. [ABSTRACT FROM AUTHOR]

Coronary restenosis is the primary unsolved problem following open heart surgery or percutaneous transluminal coronary angioplasty, and yet, it remains unknown how a pharmaceutical strategy minimizes restenosis by scaffold-based administration of several medicines. In this study, 3D-printed hexagonal polymer scaffolds of sodium alginate/hyaluronic acid/gelatin (SA/HA/Gel) loaded with heparin drug were fabricated. The morphology, physicochemical, and surface properties of the scaffolds were investigated through SEM, FTIR, porosity, wettability, water absorption, mechanical properties, biodegradability, and heparin release studies. The cell-scaffold interactions were studied by the cell attachment assays and MTT assay on L929 cell lines. The investigation demonstrated that raising the print angle resulted in 3D-printed scaffolds having higher porosity percentages, mechanical qualities, and heparin release (P < 0.05), but had no discernible impact on the scaffolds' biological properties (P > 0.05). Heparin showed a regulated slow-release behavior that was consistent with the scaffolds' rate of degradation and may be continually efficient during tissue regeneration. According to the outcomes of the in vitro biological evaluation, the 3D-printed scaffolds showed suitable cell attachment and biocompatibility (> 90%), and they were not overtly hazardous. The findings support the use of the fabricated 3D-printed SA/HA/Gel heparin-loaded scaffolds for cardiovascular tissue applications. [ABSTRACT FROM AUTHOR]

Biopolymers have a transformative role in wound repair due to their biocompatibility, ability to stimulate collagen production, and controlled drug and growth factor delivery. This article delves into the biological parameters critical to wound healing emphasizing how combinations of hydrogels with reparative properties can be strategically designed to create matrices that stimulate targeted cellular responses at the wound site to facilitate tissue repair and recovery. Beyond a detailed examination of various biopolymer types and their functionalities in wound dressings acknowledging that the optimal choice depends on the specific wound type and application, this evaluation provides concepts for developing synergistic biopolymer blends to create next-generation dressings with enhanced efficiencies. Furthermore, the incorporation of therapeutic agents such as medications and wound healing accelerators into dressings to enhance their efficacy is examined. These agents often possess desirable properties such as antibacterial activity, antioxidant effects, and the ability to promote collagen synthesis and tissue regeneration. Finally, recent advancements in conductive hydrogels are explored, highlighting their capabilities in treatment and real-time wound monitoring. This comprehensive resource emphasizes the importance of optimizing ingredient efficiency besides assisting researchers in selecting suitable materials for personalized wound dressings, ultimately leading to more sophisticated and effective wound management strategies. [ABSTRACT FROM AUTHOR]

Polyurethane (PU) nanocomposite films were prepared through a solution casting technique slightly modified by individual and simultaneous additions of a proper nonsolvent (ethanol) and graphene nanoplatelets. To this end, different nonsolvent contents and graphene functionalizations (hydrophobic and hydrophilic) were used to modify the surface properties of PU to make it more biocompatible. X‐ray diffraction patterns revealed that both types of graphene had a hampering effect on crystallization of PU from solution, while nonsolvent enhanced the PU crystallinity. According to morphological results, hydrophobic graphene showed a low dispersion quality. In contrast, the hydrophilic graphene was better dispersed and mainly localized at the bulk of the film due to its association with polar urethane groups in the hard segments. Wettability analysis, performed by water and diiodomethane, was employed to demonstrate a higher surface localization of hard segments for the samples loaded with hydrophilic graphene. Cytotoxicity analysis also showed a greater extent of cell viability for the samples loaded with hydrophilic graphene, demonstrating a direct correlation between biocompatibility and polar hydrophilic groups enriching the surface. This study shows the great potential of graphene in improving the nonsolvent‐induced phase separation to achieve a more biocompatible material. [ABSTRACT FROM AUTHOR]

Recently, nanocomposites (NCs) based on Layered Double Hydroxides (LDH) and compression polymers have attracted a lot of bioengineer's attentions. Because unlike non-composite materials, these compounds offer significant potential for superior behaviors. These materials exhibit good properties such as excellent bending, dimensional stability, cheap gas absorption, enhancement of thermal properties, ignition and mechanical delay. Such reinforcements occur in compression polymer matrices and adjustable properties of LDHs due to the intermediate effects of uniform and homogeneous dispersion of high dimensional LDH nanofillers. In the present study, polycaprolactone (PCL) polymer solutions containing different amounts of LDH (1%, 3% and 5%) were electrospun and the resulting fibers were structurally analyzed using scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis. Also, using porosity, contact angle, degradation test, mechanical strength test, cell adhesion test and quantitative toxicity test (MTT), and cellular properties were investigated. During the studies, all scaffolds had a uniform surface and diameter with the same porosity. Also, with a 1 wt% and 3 wt% LDH, the tissue diameter decreased and increased with addition of 5 wt% LDH. In addition, increased of LDH leads to decreased in the contact angle of the structure. The degradation test result showed an increase in the rate of degradation with increasing LDH amount. The results of tensile and MTT tests showed an increase in tensile strength and cell proliferation with addition of LDH reinforcement. In cell adhesion test, the highest level of adhesion was reported in the sample with 1 wt% LDH. In general, it can be concluded that the sample containing 5 wt% LDH has optimal properties compared to other scaffolds and can be proper for tissue engineering. [ABSTRACT FROM AUTHOR]

Objective(s): Many people all around the world encounter major problems due to nervous system injuries. Among the various methods of treating, neural tissue engineering has attracted a lot of attention from nerve science researchers. Materials and Methods: There are various methods for fabrication of soft tissue, however the electrospinning method (ELS) is a simple and cost-effective method that can produce porous fiber scaffolds to simulate the environment of the extracellular matrix (ECM). In this study, an ELS technique was used to fabricate polyvinyl alcohol (PVA) tissues and graphene nanosheet (Gr-NS) added with omega-3 fatty acids (O3FA) was loaded in these tissues that support nerve tissue regeneration. For this purpose, PVA and Gr-NS for biaxial ELS, PVA containing 0.5 wt%, and 1 wt% of Gr-NS was used. Then, the morphology of these scaffolds was observed by optical microscopy and scanning electron microscopy (SEM) technique. Results: The results show after loading of O3FA, the fiber diameter reaches 0.573±0.12 μm, which is within the range of dimensions required for nerve tissue engineering. FTIR analysis indicates that Gr-NS and O3FA have been well loaded in the scaffolds. The results of water absorption and biodegradation tests demonstrated that the sample with 0.5% Gr-NS has 211.98% and 16.54% water absorption and biodegradation after 48 hr and 6 days, respectively. Conclusion: Finally, the results of this study indicate that scaffolds loaded with 0.5% Gr-NS have a homogeneous, porous, and integrated structure which can be effective in nerve tissue engineering. [ABSTRACT FROM AUTHOR]

Water-based anionic urethane polymer was synthesized from the reaction of diisocyanate and polycaprolactone. Then chitosan and zinc oxide nanoparticles were added to the urethane pre-polymer as a potent antibacterial agent and a double cross-linking agent. The results of the FTIR test confirmed the synthesis of urethane pre-polymer. The results of physical properties showed that with the addition of chitosan and zinc oxide nanoparticles, water absorption and hydrophobicity of the samples increased. In addition, the results of samples' water vapor permeability showed that in the presence of chitosan, the permeability decreased compared to the permeability of pure polyurethane, which can be attributed to the cross-links of nanocomposite samples. Biocompatibility tests and antibacterial activity of the samples were also evaluated. Also, the degree of biocompatibility of the samples was analyzed by examining the morphology and growth and proliferation of fibroblast cells. The results showed that the growth and proliferation of fibroblasts in the sample had reasonable values, which could be evidence of noninterference of wound dressings in new tissue formation at the wound site. The results of antibacterial activity showed that wound dressings containing chitosan and zinc oxide had a synergistic effect on antibacterial properties against gram-positive and gram-negative bacteria. [ABSTRACT FROM AUTHOR]

The biomaterials with excellent biocompatibility and biodegradability ¬can lead to satisfactory wound healing. In this study, core-shell structured PU (polyurethane)/St (Starch) and PU/St (Hyaluronic Acid (HA)) nanofibers were fabricated with coaxial electrospinning technique. The morphology characterization of the core-shell structure of nanofibers was investigated by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images. Contact-angle measurements were confirmed the core/shell structure of the electrospun nanofibers with shell and core feed rates of 0.675 L/min and <0.135 L/min, respectively. The average fiber diameter values were calculated for polyurethane nanofibers (836 ± 172.13 nm), PU/St nanofibers (612 ± 93.21 nm) and PU/St (HA) nanofibers (428 ± 78.32 nm). The average porosity values of scaffolds were determined for PU (1.251 ± 0.235 μm), PU/St (1.734 ± 0.284 μm) and PU/St (HA) (3.186 ± 0.401 μm). The core-shell PU/St and PU/St (HA) nanofibers were evaluated in vitro by using mouse fibroblasts (L929) cells. Cell morphology and viability results were exhibited significant enhancement in cell promoting and cell attachment. Furthermore, in vivo studies was indicated Core-shell PU/St (HA) wound dressing can be an appropriate candidate for skin tissue engineering and wound healing. Unlabelled Image • PU/St and PU/St (HA) core–shell fibers are fabricated by coaxial electrospinning. • A distinct boundary between the core and shell is exhibited that PU is wrapped completely in the core. • The electrospun fibers are completely biocompatible. • The PU/St (HA) core-shell nanofibers can be a novel scaffold for wound healing and skin tissue engineering. [ABSTRACT FROM AUTHOR]

Wound healing and health care requirements have attracted more attention, and the need to develop new drug-containing dressings to accelerate wound healing is required. Carboxymethyl chitosan (CMCS)/gelatin-based films with mesoporous silica nanoparticles (MSNs) containing the Myrtus communis L. (Myrtle) aqueous extract were designed to answer this demand. Myrtle aqueous extract included total phenolic content and good free radical scavenging ability in vitro assay. The infrared spectroscopy characterized the functional groups of myrtle extract and biocomposite films. It was found that mesoporous silica nanoparticles increased the tensile strength of the flexible dressings, which is essential in therapeutic uses. MSNs influenced swelling ratio, oxygen, and water vapor permeability that indicates the CMCS/Gelatin/Myrtle/5 % MSNs wound dressing can absorb wound exudates and preserve skin moisture. Also, these biocompatible nanoparticles reduced the cytotoxicity of fibroblast cells due to the decelerated drug release. Correspondingly, silica nanoparticles affected the extract release rate and could accumulate and release the extract prolonged in CMCS/Gelatin/Myrtle/5 % MSNs models. Finally, histological analysis showed collagen growth and fibroblast migration in wounds treated with CMCS/Gelatin/Myrtle/5 % MSNs, causing proper wound contraction and accelerating wound healing in mice models. The results suggest that CMCS/Gelatin/Myrtle/5 % MSNs films have a beneficial application as wound dressings. An overview illustration of this research. [Display omitted] [ABSTRACT FROM AUTHOR]

Different types of implants are used in orthopedic applications. Due to the stress shielding and a second surgery caused by applying metal implants as orthopedic joints, using biodegradable bone implants with antibacterial properties is advantageous. Therefore, this study aims at fabricating a multifunctional poly (lactic acid) (PLA)-polycaprolactone (PCL)-based scaffold reinforced with hydroxyapatite (HA) and zinc oxide (ZnO) nanoparticles. Solvent casting combined with die-casting techniques was employed for fabricating the scaffolds, and their physical, mechanical, and biological properties were characterized. The morphology of the samples and the growth of hydroxyapatite crystals on the surface of the samples were examined by field emission scanning electron microscope. In dry conditions, adding nanoparticles to the scaffolds has significantly (p <.05) increased the tensile Young's modulus from 450.00 ± 87.18 MPa to 1050.66 ± 104.05 MPa. Also, adding ZnO has improved the antibacterial properties of the scaffolds against S.aureus and E.coli bacteria strains. Moreover, the MTT assay results (after 72 h cell culture) show that the viability of L929 cells has increased from 22.18 ± 0.62% for the PLA-PCL scaffold to 70.03 ± 0.25% for the optimal nanostructure (p <.05). In conclusion, the PCL-PLA/HA/1% ZnO scaffold could potentially be used as absorbable spongy bone implants. [ABSTRACT FROM AUTHOR]

Background. Tissue engineering is defined as the designing and engineering of structures to rebuild and repair a body damaged tissue. Scaffolding Poly Hydroxy Butyrate Valerate (PHBV) has shown good biocompatibility and biodegradable properties. Nanofibers have improved the performance of biomaterials, and could be considered effective. One of the important methods for designing nanofiber scaffold is the electrospinnig method. In this study, PHBV nanofibers were well designed and then, modified with the immobilized collagen via the plasmamethod. The samples were evaluated by ATR-FTIR, SEM, contact angle, and, finally, cell culture. Results. ATR-FTIR structural analysis showed the presence of collagen on the nanofiber surfaces. The SEM images showed the size average of nanofibers as to be about 280 nm; that increased with a collagen coating up to 300 nm. Contact angle analysis showed 67 degree for uncoated nanofibers and 56 degree for coated nanofibers. Cellular investigations (USS cells) showed better adhesion and cell growth and proliferation of coated samples than uncoated samples. Conclusions. In this work, the PHBV nanofibers with a size average about 280nm were designed. Nanofibers were successfully coated with collagen via the plasma methods. These collagen-coated nanofibers could be used well for tissue engineering. [ABSTRACT FROM AUTHOR]

In this study, bacterial cellulose (BC)/polypyrrole (PPy) and zinc nanoparticles (ZnO), which simultaneously possess antimicrobial and cell proliferation properties were introduced as a new generation of nanocomposite aerogels. Despite these outstanding features, the use of PPy solely is limited due to its low stability, poor mechanical integrity, and difficulty processing. Accordingly, ZnO nanoparticle was first added to BC with different weight percentages of 1%, 3%, and 5%, and then PPy was embedded by in situ polymerizations. The porosity of all aerogel samples was higher than 80%, and their density was below 0.5 g/cm3. Based on the Field Emission Scanning Electron Microscopy (FESEM) images, it was concluded that in the presence of PPy and ZnO within the BC structure, its fibrous and porous structure was preserved, although the structure seems denser. The FESEM images demonstrated that BC's nanofibrous and porous structure were also preserved in the coexistence of PPy and ZnO, and the microstructure of the grace grape was formed. In the ternary nanocomposite aerogels 5% ZnO, the elastic modulus and tensile strength increased. The inhibition zone's observation in the culture medium containing both Gram-positive and Negative bacteria well confirmed the antibacterial capability of the ternary nanocomposite aerogels. Also, the MTT results of L929 on aerogels showed that addition of 3% ZnO nanoparticles, cell adhesion and proliferation significantly increased over different times of culture. Schematic of preparation of cellulose/polypyrrole and zinc nanoparticles. [Display omitted] • Bacterial cellulose/polypyrrole and zinc nanoparticles were prepared for soft tissue engineering. • The prepared nanocomposite has low stability, poor mechanical integrity, and difficulty processing. • The porosity of all aerogel samples was higher than 80%, and 0.5 g/cm3 density. • The modulus and tensile strength reach to 7 GPa and 200 MPa. [ABSTRACT FROM AUTHOR]

• N -Carboxymethyl chitosan/poly(ε-caprolactone) core-shell fibers were produced. • Nickel ferrite and Doxorubicin were loaded into the nanofibers against breast cancer. • The sustained release of DOX from core-shell fibers was obtained during 25 days. • The external magnetic field and pH of 5.4 resulted in DOX release during 7 days. • Maximum cytotoxicity was 83 % using CMC/PCL/nickel ferrite 10 % core-shell fibers. The coaxial electrospinning for producing core-shell nanofibers due to control the release profile of drug by the shell layer has been developed. N -carboxymethyl chitosan (CMC)-polyvinyl alcohol (core)/poly(ε-caprolactone) (PCL) (shell) nanofibers were produced via coaxial electrospinning. Doxorubicin (DOX) and nickel ferrite nanoparticles were incorporated into the nanofibers for controlled release of DOX against MCF-7 breast cancer. The minimum CMC/PCL fiber diameter was found to be 300 nm by optimizing of three variables including voltage to distance ratio (1.5–2.5 kV/cm), CMC concentration (4−6 wt.%) and PCL concentration (8−12 wt.%). The synthesized core-shell fibers were characterized using FTIR, XRD, SEM, and TEM analysis. The extended release and controlled release of DOX from core-shell nanofibers were achieved under physiological pH without external magnetic field (EMF) and acidic pH with EMF during 25 and 7 days, respectively. The maximum cytotoxicity of MCF-7 breast cancer cells was about 83 % using CMC/PCL/nickel ferrite 10 % nanofibers and EMF. [ABSTRACT FROM AUTHOR]

Herein, superhydrophobic and antibacterial polyurethane (PU) nanocomposite films loaded with titanium dioxide (TiO 2) nanoparticles and graphene nanoplatelets were fabricated via a spray coating technique. The nonsolvent-induced phase separation (NIPS) process increased the films' roughness and hydrophobicity. In addition to the effective role of nonsolvent in phase separation, graphene also played the nucleating role and promoted the NIPS process. Based on scanning electron microscopy, atomic force microscopy, and optical microscopy results, it was found that the combinational use of TiO 2 , graphene, and nonsolvent leads to a hierarchical structure with a high extent of uniform surface roughness resulting in a superhydrophobic/roll-off behavior (water contact angle = 159°, sliding angle < 5°). The antibacterial activity was profoundly increased to ca. 99% against S. aureus and E. coli bacteria and was attributed to the induced superhydrophobicity and also the surface localization of TiO 2 as a biocidal agent. An attempt was also made to present a mechanism for the NIPS process in the presence of TiO 2 and graphene nanoparticles. • Superhydrophobic surfaces based on PU/TiO 2 /graphene were fabricated via spray coating. • Promising potential of graphene as nucleating agents in NIPS process was demonstrated. • Enhanced phase separation caused the surface layer to be highly enriched by TiO 2. • Combination of superhydrophobicity and surface localization of TiO 2 led to high antibacterial rates. [ABSTRACT FROM AUTHOR]

Electrospinning has been extensively accepted as one of most important techniques for fabrication of scaffolds for bone tissue engineering. Polycaprolactone is one of the most applied electro-spinned scaffolds. Since low mechanical strength of polycaprolactone scaffold leads to the limitation of its applications, composition of polycaprolactone with ceramic particles is of great interest. Several studies have been conducted on fabrication and characterization of polycaprolactone nanocomposite scaffolds, but none of these researches has used mesoporous silica particles (KIT-6). In this project, a high-strength and bioactive nanocomposite scaffold has been developed which consists of polycaprolactone and mesoporous silica particles. Results showed that increase of KIT-6 particles percentages up to 5% leads to the enhancement of tensile strength of scaffold from 1.8 ± 0.2 to 2.9 ± 1.0 MPa. Although wettability of scaffolds in presence of particles was totally lower than pure PCL scaffold, but increase of particles percentages led to enhancement of wettability and water absorption of scaffolds. On the other hand presence of KIT-6 particles increased specific surface area and also bioactivity of scaffold was increased by enhancement of ion exchange between surface and simulated body fluid. Finally it was concluded that PCL-KIT-6 scaffolds are a suitable candidate for application in tissue engineering. • Increase of KIT-6 particles percentages up to 5% leads to the enhancement of tensile strength of scaffold from 1.8 ± 0.2 to 2.9 ± 1.0 MPa. • Increase of particles percentages led to enhancement of wettability and water absorption of scaffolds. • Presence of KIT-6 particles increased specific surface area and also bioactivity of scaffold was increased by enhancement of ion exchange between surface and simulated body fluid. [ABSTRACT FROM AUTHOR]

Objective(s): Bioresorbable scaffolds have been advocated as the new generation in interventional cardiology because they could provide temporary scaffolds and then disappear with resorption. Although, the available stents in clinical trials exhibited biosafety, efficacy, no death, and no apparent thrombosis, Mg-substrate degradation on drug release has not been investigated. Materials and Methods: Therefore, more research has been needed to legitimize the replacement of current stents with Mg-based stents. UV-Vis spectrophotometer, scanning electron microscope (SEM), X-ray diffraction (XRD), pH measurement, H₂ evolution, and corrosion tests determined the change in hybrid properties and drug release rate. Results: The effect of Mg degradation on drug release from poly-L-lactide (PLLA) specimen was much higher than that of the L605/PLLA sample. Hydrogen evolution caused by magnesium degradation compelled everolimus out without significant PLLA decomposition during the first 100 days, while formation of Mg(OH)2 caused the PLLA to deform and crack. Conclusion: A combined mechanism of lattice/hole diffusion-dissolution governed the release of everolimus with the activation energies of 5.409 kJ/mol and 4.936 kJ/mol for the first 24 hr and diffusion coefficients 6.06×10-10 and 3.64×10-11cm2/s for the 50th to 100th days. Prolonged suppression of hyperplasia within the smooth muscle cells by hybrid stent insertion could bring about the cessation of restenosis. [ABSTRACT FROM AUTHOR]

The clinical efficacy of tissue plasminogen activator (tPA) is limited by its lack of specific delivery, requiring large therapeutic doses that increase the risk of intracerebral hemorrhage, bleeding at the surgical site, and patient mortality after angioplasty. To address these limitations, this study aimed to develop a chitosan polysulfate (CsPs)-coated liposomal formulation for the sustained release of tPA. The CsPs-coated liposomes containing tPA (Liposome-tPA/CsPs) were fabricated using the thin-film hydration technique and their properties were compared to tPA-encapsulated nanoliposomes without a coating layer (Liposome-tPA). Liposome-tPA/CsPs showed a quasi-spherical morphology with a hydrodynamic diameter of 110 nm, while Liposome-tPA had a diameter of 80 nm. The thermal analysis showed that the degradation temperature and glass transition temperature (Tg) of Liposome-tPA/CsPs were higher than that of tPA alone, indicating improved temperature stability. The in vitro release study demonstrated a slow and sustained release of tPA from the Liposome-tPA/CsPs, with a concentration of 0.02 mg/ml at 1 h and 0.23 mg/ml at 180 h. The CsPs coating layer enhanced the antibacterial and antioxidant activity of the nanoliposomes. Liposome-tPA/CsPs exhibited higher cell viability compared to Liposome-tPA. It also achieved a higher percentage of thrombolysis, with complete clot dissolution observed after 3 h of treatment. These findings suggest that the Liposome-tPA/CsPs can be a promising approach to overcome the limitations associated with the systemic administration of tPA, potentially enhancing its clinical efficacy while reducing the risk of adverse events. [Display omitted] • tPA-loaded nanoliposomes with CsPs coatings were fabricated by thin-film hydration technique. • CsPs coating layer improved the antibacterial effect and antioxidant activity of Liposome-tPA. • The release of tPA from CsPs-coated nanoliposomes was a slow and sustained release. • Liposome-tPA/CsPs enhanced the blood clot dissolution compared to the tPA alone. • Liposome-tPA/CsPs can be used for the treatment of the patients with the vascular occlusion. [ABSTRACT FROM AUTHOR]

Wound healing is one of the most complex processes that our body has to do, which in some cases is not able to heal itself and needs external stimuli. Controlling wound progression, increasing quality, and accelerating wound healing is the key to solving this global challenge. The use of biological agents in wound dressings is an effective way to modify all aspects of wound healing and has the potential to guide the healing process toward greater recovery. Bio-nanocomposites have always been considered as one of the pre-designed materials and received the attention of bioengineer researchers. In this research, Tragacanthin Gum-Carboxymethyl Chitosan (TG-CMC) bio-nanocomposite wound dressing containing akermanite nanoparticles with different weight percentages of AgO–TiO 2 was fabricated using the freeze-drying method. The objectives of this study were to investigate tensile strength, bioactivity, and biodegradability properties. The physical and chemical properties of the wound dress were assessed using X-ray diffraction (XRD), Fourier Transform Infrared Spectroscope (FTIR), and Scanning Electron Microscope (SEM) techniques. Also, the bioactivity and biodegradability of wound dressings were characterized by immersion of samples in Phosphate Buffer Saline (PBS). As a result, the toxicity test of the sample containing 10 wt % AgO–TiO 2 oxides has the lower toxicity about 0.943–0.948. The obtained results show that the porosity of the wound dressings is about 65%–79%, which increases by 0.8 with the addition of Ag–TiO 2 nanoparticles. As the percentage of porosity increased, it was determined that the tensile strength of the wound patches decreased from 0.35 MPa to 0.15 MPa. The wound dress weight loss results show that the highest weight loss belongs to the sample containing the highest amount of AgO/TiO 2. Therefore, the pure sample and the sample with 15 wt% have weight loss about 75% and 81%. The results show that the samples were porous and had interconnected porosities which increased in the presence of akermanite nanoparticles. • Bio-nanocomposite wound dressing was fabricated using the freeze-drying method. • We investigate tensile strength, bioactivity, and biodegradability properties. • The properties of the wound dress were assessed using XRD, FTIR, and SEM. • Porosity of the wound dressings is about 65%–79%, which increased by 0.8 with the addition of silver-TiO 2. • Samples were porous and had interconnected porosities which increased in the presence of akermanite nanoparticles. [ABSTRACT FROM AUTHOR]

The application of green-approach synthesized biopolymers for using in tissue engineering fields has grabbed much of scientific attentions in the last decade. The main cause behind this attention is related to the biocompatibility and biodegradability of these new synthesized materials. One of the most indispensable challenge in tissue engineering problems is the development of a new substrates, possessing similar morphological structures to natural extracellular matrices. In this research, an innovative tubular bionanocomposite blends based on the elastomeric polyester of poly (glycerol sebacate) (PGS) and poly caprolactone (PCL) containing nanoclay or graphene oxide (GO) are produced and used in soft tissue engineering applications. FESEM images show that the incorporation of nanoparticles dictates ordered porous texture within bionanocomposite blends. Besides, exfoliated morphology regarding blends containing GO and nanoclay is observed by XRD results. The incorporation of GO into PCL/PGS blends, besides the increment of storage modulus, increases the value of Tg from -25 °C (PCL/PGS blend) to -17 °C. Moreover, a contact angle value of 53° is determined for this sample. Furthermore, the cellular adhesion and proliferation of PCL/PGS blend containing nanoclay or GO are even comparable to that of the culture plate, exhibiting their biocompatibility and potential application in the biomedical area. [ABSTRACT FROM AUTHOR]

In this work, a novel environmentally friendly semi-interpenetrating anionic hydrogel based on Xanthan gum/cross-linked polyacrylic acid/graphene oxide was prepared as superabsorbent for removing methylene blue as cationic dye from the water. Acrylic acid (AA) was crosslinked in xanthan (XG)/graphene oxide (GO) solution by a novel synthetic acrylic-urethane crosslinker (MS). Various analyses such as SEM, FT-IR, 1H NMR, XRD, and TGA were used to study morphology, structure, and thermal stability of MS and semi-IPNs. The synthesized hydrogels showed pH-sensitive behavior in water uptake, with the highest and lowest swelling in alkaline and acidic media, respectively. The nanocomposites had better dimension stability and dye adsorption with increasing GO from 0 to 1%. Hydrogel containing 1% GO showed 485% and 88.5% swelling and dye adsorption efficiency, respectively. Different kinetic models including 1st order, 2nd order, intra-particle diffusion, and Elovich kinetics were studied. All models except 2nd order model are in good agreement with the experimental data. GO-containing hydrogels had a significant effect on methylene blue adsorption and this effect increased with an increase in the amount of GO. PAA/XG/GO hydrogels can be introduced as an eco-friendly adsorbent with high efficiency for the removal of cationic dye pollutions. Unlabelled Image [ABSTRACT FROM AUTHOR]

• Fabricating of a new shape memory polymer composites based on thermoplastic polyurethane (TPU) containing three types of graphinic particles: graphene oxide (GO) and reduced graphene oxide (rGO) and hybrid GO:rGO. • Evaluation of localization of GO and rGO particles into soft and hard segments of TPU matrix. • Tailoring a bridge between microstructure and macro-properties of TPU composites comprising 1, 2 and 5 wt% filler concentration. • Characterization of heat actuating of TPU composites with DMTA instrument. • Using of hybrid GO:rGO particles into the shape memory of TPU and find superior mechanical strength, the excellent shape fixity and high actuation value. We fabricated shape memory composites based on thermoplastic polyurethane (TPU) containing three types of graphene, that is, graphene-oxide (GO), reduced graphene-oxide (rGO) and hybrid GO:rGO (ratio 1:1) to study their mechanical and shape memory properties. Tailoring a bridge between microstructure and macro-properties of TPU composites comprising 1, 2 and 5 wt% filler concentration was the primary aim of this work. Incorporation of GO and rGO platelets into the TPU matrix augmented the modulus, elongation at break and breaking stress compared to that of pristine TPU. Besides, the TPU/rGO composites revealed greater young modulus, %elongation, storage modulus, and %crystallinity compared to TPU/GO composites at similar filler content. In particular, the TPU/GO:rGO composites displayed the synergic improvement in dynamic and static mechanical properties owing to the systematic localization GO and rGO platelets in hard and soft segments of TPU, respectively. Interestingly, this localization was thermodynamically predicted by the solubility parameter of components and approved with microscopic observation. The TPU composite behavior was further examined by relaxation stress analysis. While the GO platelets have no significant influence on shape recovery behavior as compared to rGO filled composites, on the other hand, the shape fixation is deteriorated by adding the rGO platelets. The shape memory assessment clarified that the simple TPU composites comprising GO(2 wt%) and rGO(5 wt%) have the highest value in shape fixity and shape recovery, respectively. Noteworthy, both shape fixity and recovery of TPU composites improved when simultaneously using the rGO and GO platelets (GO:rGO) as hybrid filler. The shape recovery and fixity value of 5 wt% TPU composite containing hybrid GO:rGO is 96.7% and 99.1%, respectively, which it has increased up 1.12, 1.05 and 1.02-fold in shape recovery that of neat TPU, 5 wt% TPU composite containing GO and rGO, respectively. This study proves that incorporation of hybrid GO:rGO into shape memory TPU matrix can be employed effectively to attain superior mechanical strength, the excellent shape fixity and high actuation value. [ABSTRACT FROM AUTHOR]

• Introducing ternary BC based aerogels containing sequence additives (Ag and PANI). • The order of addition of PANI and Ag had significant effects on aerogel properties. • Ternary aerogel of BC/Ag/PANI showed high flexibility and conductivity properties. • BC/Ag/PANI revealed energy density of 34 Wh kg−1 at a power density of 459 Wh kg−1. • The capacitance behavior of BC/Ag/PANI was excellence than that of BC/PANI/Ag. The fabrication of flexible, freestanding, lightweight, renewable, low cost and also the high performance of novel supercapacitors is pivotal in electronic fields. In this work, two series of ternary bio-nanocomposite flexible aerogels based on bacterial cellulose (BC) as a template and containing silver nanoparticles (AgNPs) and polyaniline (PANI) as conductive agents facilely fabricate using an in situ method, in which Ag and PANI embedded within BC matrix as sequences. Morphology of ternary aerogels reveals the core-shell and branch-grape microstructures for BC/Ag/PANI and BC/PANI/Ag samples, respectively. BET analysis exhibits that specific surface area of BC/Ag/PANI (145 m2 g−1) is higher than BC/PANI/Ag (130 m2 g−1) aerogel. Electrical conductivity measurements indicated that BC/Ag/PANI (1.25 S cm−1) possesses higher electrical conductivity than BC/PANI/Ag (0.00693 S cm−1) aerogels. The coexistence of PANI and Ag within BC texture, significantly altered the interfacial polarization and relaxation spectra of ternary system. A specific capacitance 357 F g−1 at 0.5 A g−1 associated with 83% cyclic stability over 2000 cycles is observed for BC/Ag/PANI , while BC/PANI/Ag showed specific capacitance of 232 F g−1 at 0.5 A g−1 as well as 74% capacitance retention. Furthermore, in symmetrical supercapacitor setup for BC/Ag/PANI , a high energy density of 34 Wh kg−1 at a power density of 459 Wh kg−1 is obtained. These findings indicated that BC/Ag/PANI aerogel as a flexible and lightweight electrode could be highly used in the field of electrical energy storage. [ABSTRACT FROM AUTHOR]

A major challenge in managing coronary artery disease is to find an effective thrombolytic therapy with minimal side effects. Laser thrombolysis is a practical procedure to remove the thrombus from inside blocked arteries, although it can cause embolism and re-occlusion of the vessel. The present study aimed to design a liposome drug delivery system for the controlled release of tissue plasminogen activator (tPA) and delivery of drug system into the thrombus by Nd:YAG laser at a wavelength of 532 nm for the treatment of arterial occlusive diseases. In this study, tPA encapsulated into the chitosan polysulfate-coated liposome (Lip/PSCS-tPA) was fabricated by a thin-film hydration technique. The particle size of Lip/tPA and Lip/PSCS-tPA was 88 and 100 nm, respectively. The release rate of tPA from Lip/PSCS-tPA was measured to be 35 % and 66 % after 24 h and 72 h, respectively. Thrombolysis through the delivery of Lip/PSCS-tPA into the thrombus during the laser irradiation was higher compared to irradiated thrombus without the nanoliposomes. The expression of IL-10 and TNF-α genes was studied by RT-PCR. The level of TNF-α for Lip/PSCS-tPA was lower than that of tPA, which can lead to improved cardiac function. Also, in this study, the thrombus dissolution process was studied using a rat model. After 4 h, the thrombus area in the femoral vein was significantly lower for groups treated with Lip/PSCS-tPA (5 %) compared to the groups treated with tPA alone (45 %). Thus, according to our results, the combination of Lip/PSCS-tPA and laser thrombolysis can be introduced as an appropriate technique for accelerating thrombolysis. [Display omitted] • tPA-encapsulated PSCS-coated liposome was fabricated by thin-film hydration method. • The level of TNF-α for Lip/PSCS-tPA was lower than that of tPA alone. • The thrombus dissolution was performed using both Lip/PSCS-tPA and Nd:YAG laser. • The thrombus dissolution by laser and nanodrug system was observed in the following order, Lip/PSCS-tPA > Lip/tPA > tPA. • Sustained and controlled release of tPA from Lip/PSCS-tPA can prevent re-occlusion of the vessel. [ABSTRACT FROM AUTHOR]

[Display omitted] • Successfully synthesized a new bio polyester PXDDA (Poly(Xylitol-Dodecanedioic acid)) from renewable resources. • Using in-situ polymerization technique for preparing bio nanocomposites. • Controlling hydrophilic properties of PXDDA by using Lactic acid (LA) monomers and bio active glass nanoparticles (n-BG) • Observation of high changes in polymeric chains in PXDDA with presence LA in backbone of macromolecules. Introducing new biomaterials is necessary for developing tissue engineering science. Soft tissue engineering need to high soft and stretchable properties and then innovation of bio rubbers based on natural materials is very important. In this research by using of the polymerization science and the chemical reaction between Xylitol, Dodecanedioic acid (DDA) and Lactic acid (LA) a new biopolymers were obtained. The samples were provided based on mole fraction of LA and weight percentages of bioglass nanoparticles (n-BG). Reaction between all of monomers were investigated by using Fourier-transform infrared spectroscopy (FTIR) and proton nuclear magnetic resonance (1H NMR) analysis. Also scanning electron microscope (SEM) and Mapping analysis show that the LA has had the necessary effectiveness on the morphology. The dynamic contact angle illustrated that hydrophilic properties of the polymeric samples have decreased in presence of LA and n-BG had positive effects in degrees of hydrophilic properties. The investigation of viscoelastic properties demonstrate that nanoparticles caused the storage modulus to increase and the presence of LA monomers has changed the glass transition temperature (T g) from −2.6 °C to 21.7 °C in nanocomposite samples. Hydro-catalytic degradation test show that presence LA monomers decreases the degradation rate. [ABSTRACT FROM AUTHOR]

• Porous superhydrophobic PVC films were applied onto the surface of TPU sheets. • Intrinsically hydrophilic silver phosphate nanoparticles were synthesized and added to films. • A proper combination of nonsolvent and nanoparticles led to self-cleaning behavior. • Combination of superhydrophobicity and antibacterial nanoparticles led to an efficient antibacterial behavior. This study aims to induce antibacterial and superhydrophobic properties on the surface of thermoplastic polyurethane (TPU) sheets via an improved phase separation process through application of polyvinyl chloride (PVC) thin films. Porous PVC thin films were produced using different amounts of ethanol as nonsolvent. However, the created porosity was not sufficient to achieve superhydrophobicity. To improve the phase separation process, the silver phosphate nanoparticles were first synthesized and then added to the solution. According to scanning electron microscopy and X-ray photoelectron spectroscopy results, the nanoparticles were majorly localized at the bulk of PVC films. A direct relationship was found between the level of porosity and superhydrophobicity. An exceedingly high amount of nanoparticles had a deteriorating influence on porosity and superhydrophobicity. The optimum sample was found to be durable against liquids with different pH values. In contrast to the good resistance of superhydrophobic sample at elevated temperatures (80 °C), a sticky behavior was obtained upon exposure to 120 °C. The level of bacterial adhesion for the superhydrophobic sample was drastically declined (>99%) with respect to the pure PVC film in case of S. aureus and E. coli bacteria after an incubation time of 24 h. In conclusion, the hybrid of superhydrophobic behavior and an antibacterial material such as silver phosphate nanoparticles exhibited a promising potential in achieving antibacterial surfaces. [ABSTRACT FROM AUTHOR]