Preparation of hydrophilic polycaprolactone/modified ZIF-8 nanofibers as a wound dressing using hydrophilic surface modifying macromolecules

Carboplatin-loaded zeolitic imidazolate framework-8: Induction of antiproliferative activity and apoptosis in breast cancer cell

The challenge with breast cancer is its ongoing high prevalence and difficulties in early detection and access to effective care. A solution lies in creating tailored metal-organic frameworks to encapsulate anticancer drugs, enabling precise and targeted treatment with less adverse effects and improved effectiveness. Zeolitic imidazolate framework-8 (ZIF-8) and carboplatin (CP)-loaded ZIF-8 were synthesized and characterized using various analytical techniques. High Resolution-transmission electron microscopy of ZIF-8 and CP@ZIF-8 indicates that the particles had a spherical shape and were nanosized. The drug release rate of CP is 98% under an acidic medium (pH 5.5) because of the dissolution of ZIF-8 into its coordinating ions, whereas 35% in a physiological medium (pH 7.4) with the addition of CP, the high porosity, and pore diameter of ZIF-8 decrease from 1243 to 1041 m2/g. Breast cancer MCF-7 cells were shown greater IC50 in CP@ZIF-8 (15.01 ± 3.03 µg/mL) than free CP (34.98 ± 4.25 µg/mL) in an in vitro cytotoxicity assessment. The cytotoxicity of the CP@ZIF-8 against MCF-7 cells was studied using the methylthiazolyldiphenyl-tetrazolium bromide method. The morphological changes were examined using fluorescent staining (acridine orange-ethidium bromide and Hoechst 33258) methods. The comet assay assessed the DNA fragmentation (single-cell gel electrophoresis). The results from the study revealed that CP@ZIF-8 can be used in the treatment of breast cancer.

Antibacterial and bioactive composite hydrogels from carrageenan-PVA-chitosan incorporated ZiF-8@GO for wound healing: in vitro and in vivo evaluations

Hydrogels are promising dressings for wound healing as they resemble the native extracellular matrix that provides a microenvironment for skin wound healing. Herein, we have developed composite hydrogels by incorporating ZiF-8@GO into the polymeric mixture of chitosan (CS), polyvinyl alcohol (PVA), and carrageenan (CG). These were analyzed using FTIR, XRD, SEM-EDX, and DSC to study their structural, surface morphology, elemental analysis, and thermal stability. The physicochemical properties were studied in different media under various pH at 37 °C. The degradation was performed in phosphate buffer saline solution at 37 °C under 7.4 pH, and the wettability was conducted to study the hydrophilicity and hydrophobicity. All the composite hydrogels are hemocompatible and exhibit excellent anti-bacterial activities against Gram-positive and Gram-negative bacteria. We have performed in-vitro biological assays using fibroblast (3t3) cell lines, and increasing ZiF-8@GO increased cell viability and proliferation. The wound contraction was also performed using an in-vivo wound healing model using SD-rat, and hydrogel (CPC-Z@GO-3) was found to heal the wound quickly without any scar formation. These hydrogels have exhibited excellent physicochemical characteristics and biological properties, which would be promising composite polymeric materials for wound repair and regeneration.

Alginate-gelatin composite hydrogels loading zeolitic imidazolate framework-8 (ZIF-8) nanoparticles on gauze for burn wound healing: In vitro and in vivo studies

This study addresses the limitations of traditional antibiotic treatments for burn wound dressings, which often lead to microbial resistance. It explores the development of innovative burn wound dressings by incorporating Zeolitic Imidazolate Framework-8 (ZIF-8) into alginate-gelatin (Al-Gl) hydrogels on gauze. Al-Gl patches with 0 %, 1 %, and 4 % ZIF-8 were fabricated and characterized using XRD, FTIR, FESEM, and EDX. Swelling, degradation, antibacterial activity, and biocompatibility were also evaluated, alongside in vivo wound healing using a Wistar rat model. FESEM confirmed ZIF-8 nanoparticles with hexagonal morphology (170-220 nm). The swelling ratio decreased from 600 % (Al-Gl 0 %) to 130 % (Al-Gl 4 %) over 10 h, and degradation rates increased from 50 % to over 70 %. Al-Gl 4 % patches demonstrated 99 % antibacterial efficacy against E. coli and S. aureus, compared to <5 % in Al-Gl 0 %. Biocompatibility was confirmed with over 90 % cell viability in MTT assays. In vivo studies showed Al-Gl 4 % achieved 89.40 % ± 3.21 % wound closure, significantly outperforming controls. Histological analyses confirmed enhanced tissue regeneration. These findings demonstrate that ZIF-8 significantly boosts antibacterial properties and wound healing, positioning ZIF-8 hydrogels as promising candidates for advanced burn wound care.

Colorimetric core/shell ZIF-8/PEO/PDA nanofibers for detection of fish spoilage

Here, colorimetric nanofibers (NFs) based on polydiacetylene (PDA), zeolitic imidazolate framework-8 (ZIF-8), and poly(ethylene) oxide (PEO) were developed. First, the successful synthesis of ZIF-8 was illustrated with structural and morphological analysis. Next, shell/core PDA/PEO/ZIF-8 NFs, namely PPZ0, PPZ5, PPZ15, and PPZ25, were fabricated by coaxial electrospinning at various ZIF-8 concentrations in the core. PPZ5 NFs exhibited a 63 % increase in tensile strength while PPZ25 NFs showed the highest thermal resistance. PPZ15 NFs with the best physicochemical and colorimetric properties were selected to evaluate food spoilage. The change in color difference values of PPZ15 NFs was correlated well with total viable count (TVC) and total volatile basic nitrogenous (TVB-N) in fish samples during chilled storage, reaching TVC to 6.69 log CFU/g, and TVB-N to 33.13 mg N/100 g on day 6. Ultimately, the PPZ15 NFs were successfully utilized to provide a real-time, quantitative assessment of fish freshness.

Electrospun zeolitic imidazole framework-8 loaded silk fibroin/polycaprolactone nanofibrous scaffolds for biomedical application

The development of electrospun nanofibrous scaffolds (NFSs) have aroused much attraction in the field of biomedical engineering, due to their small fiber diameter, high specific surface area, and excellent extracellular matrix comparability. The main focus of this study is to design and fabricate novel zeolitic imidazole framework-8 (ZIF-8)-loaded silk fibrin/polycaprolactone (SF/PCL) nanofiber composite scaffolds by using the electrospinning strategy. Firstly, ZIF-8 was synthesized and characterized, which showed remarkable features in terms of shape, size, chemical and physical properties. Then, three different amounts of ZIF-8 were encapsulated into SF/PCL nanofibers during electrospinning, to investigate how the addition of ZIF-8 affected the morphology, and structure, as well as physical, mechanical, and biological properties of the nanofiber composite scaffolds. It was found that the addition of ZIF-8 didn't change the nanofibrous morphology of the composite scaffold, and no bead-like structure were found for the SF/PCL composite scaffolds loading with or without ZIF-8. The appropriate addition of ZIF-8 could significantly increase the mechanical properties of SF/PCL NFSs. The SF/PCL NFS containing 5% ZIF-8 showed high ultimate stress and initial modulus, which were 40.31 ± 2.31 MPa, and 569.19 ± 21.38 MPa, respectively. Furthermore, the MTT assay indicated that the pure SF/PCL scaffold and one with 1% ZIF-8 exhibited nearly identical cell compatibility toward human dermal fibroblast (HDF) cells, but some obvious cytotoxicity was observed with the increase of ZIF-8 content. However, the incorporation of ZIF-8 into SF/PCL NFSs was found to have excellent antibacterial rate against both E. coli and S. aureus. In all, the incorporation of 1% ZIF-8 could impart the SF/PCL NFS with balanced bio-function, making it a promising candidate for diverse biomedical applications such as tissue engineering and wound healing.

Electrospun nanofibrous membranes meet antibacterial nanomaterials: From preparation strategies to biomedical applications

Electrospun nanofibrous membranes (eNFMs) have been extensively developed for bio-applications due to their structural and compositional similarity to the natural extracellular matrix. However, the emergence of antibiotic resistance in bacterial infections significantly impedes the further development and applications of eNFMs. The development of antibacterial nanomaterials substantially nourishes the engineering design of antibacterial eNFMs for combating bacterial infections without relying on antibiotics. Herein, a comprehensive review of diverse fabrication techniques for incorporating antibacterial nanomaterials into eNFMs is presented, encompassing an exhaustive introduction to various nanomaterials and their bactericidal mechanisms. Furthermore, the latest achievements and breakthroughs in the application of these antibacterial eNFMs in tissue regenerative therapy, mainly focusing on skin, bone, periodontal and tendon tissues regeneration and repair, are systematically summarized and discussed. In particular, for the treatment of skin infection wounds, we highlight the antibiotic-free antibacterial therapy strategies of antibacterial eNFMs, including (i) single model therapies such as metal ion therapy, chemodynamic therapy, photothermal therapy, and photodynamic therapy; and (ii) multi-model therapies involving arbitrary combinations of these single models. Additionally, the limitations, challenges and future opportunities of antibacterial eNFMs in biomedical applications are also discussed. We anticipate that this comprehensive review will provide novel insights for the design and utilization of antibacterial eNFMs in future research.

Gold/platinum nanorods/temozolomide-UiO-66-NH2 metal-organic frameworks incorporated to chitosan-grafted polycaprolactone/polycaprolactone core-shell nanofibers for glioblastoma treatment during chemo-photothermal therapy

The use of biocompatible metal-organic frameworks (MOFs) and electrospun nanofibrous implants shows promise in preventing the recurrence of postsurgical glioblastoma. In this study, temozolomide (TMZ) and platinum‑gold nanorods (PtAu NRs) were encapsulated into the UiO-66-NH2 MOFs. These were then incorporated into the chitosan-grafted polycaprolactone (PCL) (core)/PCL (shell) nanofibers coated with PtAu NRs for extended release of TMZ during chemo-photothermal therapy against glioblastoma cells. The drug encapsulation efficiency, TMZ release, and in vitro cell viability were investigated for the MOFs, simple nanofibers, core-shell nanofibers, and MOFs-nanofibers. The extended release of TMZ occurred over 44 and 36 days from the core-shell nanofibers coated with PtAu NRs under NIR irradiation at pH values of 7.4 and 5, respectively. The maximum killing of U87 glioblastoma cells was 80.2 % using TMZ-Pt-Au-MOF-core-shell nanofibers coated with PtAu under NIR irradiation. The relative tumor size for the mice bearing glioblastoma and treated with pure core-shell nanofibers, TMZ-Pt-Au-MOF, and TMZ-Pt-Au-MOF-core-shell nanofibers coated with PtAu without NIR irradiation and with NIR irradiation was 4.12, 2.12, 1.65, 0.86, and 0.48, respectively, after 30 days. The synthesized MOF-core-shell nanofibers-Pt-Au NRs implantable device shows potential as a new approach for postsurgical glioblastoma treatment during chemo-photothermal therapy.

Electrospun lignin-loaded artificial periosteum for bone regeneration and elimination of bacteria

Recently, the non-negligible role of the periosteum in bone repair has attracted the attention of researchers. In this study, poly(ε-caprolactone) (PCL)/lignin nano-fibrous membranes prepared by electrospinning are proposed as an artificial periosteum. Both in vitro and in vivo studies confirmed that PCL/lignin membranes have a pro-osteogenic effect. This effect was dependent on the lignin concentration, and there was an optimal concentration at which the membrane possessed the highest osteogenesis-potentiating activity among those tested in this study. In addition, the PCL/lignin membranes exhibited promising antibacterial properties against both E. coli and S. aureus, with high lignin concentrations corresponding to high-bactericidal activity. The prepared PCL/lignin membranes displayed promising osteogenic and antibacterial properties. With satisfactory hydrophilicity and mechanical properties, they hold great potential in serving as an artificial periosteum for bone tissue repair. This study provides both theoretical and laboratory evidence for the application of the renewable resource lignin in the repair of the periosteum and bone injuries.

Tannic acid-reinforced soy protein/oxidized tragacanth gum-based multifunctional hemostatic film for regulation of wound healing

With recent advances in the field of tissue engineering, composite films with biocompatibility, antimicrobial properties, and wound healing properties have gained potential applications in the field of wound dressings. In this research work, composite films of soy protein (S)/oxidized tragacanth gum (G) were successfully made using the solution casting process. The metal-organic framework containing curcumin (MOF) with concentrations of 5 and 10 wt% and tannic acid (TA) with concentrations of 6 and 12 wt% were entered into the polymer film. Surface morphology with scanning electron microscope (FE-SEM), thermal stability, mechanical properties, chemical structure, antioxidant, water absorption, cell viability, antibacterial activity, and biodegradability of the prepared films were investigated in laboratory conditions. In addition, the toxicity of the films in the cell environment was investigated, and the results showed that cell growth and proliferation improved in the presence of the prepared films, especially films SG/MOF10/TA6 and SG/MOF10/TA12 due to the presence of TA and MOF containing curcumin. Also, the antibacterial activity of the films showed that the presence of tannic acid and curcumin in the structure of the films increases their ability against pathogens. According to the obtained results, the newly produced nanocomposite film (SG/MOF10/TA12) has a high potential to be used for wound dressing due to its favorable characteristics and was considered the optimal film.

Implantable Zinc Ion Battery and Osteogenesis-Immunoregulation Bifunction of Its Catabolite

Biocompatible batteries can power implantable electronic devices and have broad applications in medicine. However, the controlled degradation of implantable batteries, the impact of battery catabolites on surrounding tissues, and wireless charging designs are often overlooked. Here, we designed an implantable zinc ion battery (ZIB) using a gelatin/polycaprolactone-based composite gel electrolyte. The prepared ZIBs deliver a high specific capacity of 244.0 mA h g-1 (0.5C) and long cycling stability of 300 cycles (4C). ZIBs were completely degraded within 8 weeks in rats and 30 days in a phosphate-buffered saline lipase solution, demonstrating good biocompatibility and degradability. ZIBs catabolites induced macrophage M2 polarization and exhibited anti-inflammatory properties, with mRNA levels of the M2 markers Arg-1 and CD206 up-regulated 15.8-fold and 13.4-fold, respectively, compared to the blank control group. Meanwhile, the expressions of two typical osteogenic markers, osteopontin and osteocalcin, were up-regulated by 3.6-fold and 5.6-fold, respectively, demonstrating that designed ZIBs promoted osteogenic differentiation of bone marrow mesenchymal stem cells. Additionally, a wireless energy transmission module was designed using 3D printing technology to realize real-time charging of the ZIB in rats. The designed ZIB is a promising power source for implantable medical electronic devices and also serves as a functional material to accelerate bone repair.

Smart Bandage Based on a ZIF-8 Triboelectric Nanogenerator for In Situ Real-Time Monitoring of Drug Concentration

For chronic wounds, frequent replacement of bandages not only increases the likelihood of secondary damage and the risk of cross infection but also wastes medication. Therefore, in situ real-time monitoring of the concentrations of residual drugs in bandages is crucial. Here, we propose a novel strategy that combines a triboelectric nanogenerator (TENG) with medical bandages to develop a smart bandage based on zeolite imidazolate framework TENG. During the process of wound healing, the electrical output of TENG changes with the continuous release of drugs. Based on the correlation between the electrical signal of TENG and drug concentration, the concentration of residual drugs in the bandage can be monitored in real-time in situ, guiding medical staff to replace the bandage at the most appropriate time. The smart bandage based on TENG provides a new strategy for in situ real-time monitoring of drug concentration and also provides an ideal and feasible solution for the field of biomedical drug sensing.

Design and development of pH-responsive levofloxacin-loaded metal-organic framework for the promising treatment of pediatric abdominal wound repair

With over 9 million fatalities per year expected by 2030, infectious diseases will remain a significant burden on the world economy and cause high mortality rates. An excellent method to increase the bioactivity of levofloxacin (LEV) in pediatric abdominal wound repair is the finding of a stimuli-based drug delivery system (DDS). We designed and developed an LEV incorporated with zeolite imidazole framework-8 (ZIF-8) as a promising nanocarrier for wound healing applications. The spectral analysis and morphological analysis confirm the formation of our newly fabricated composites. Mouse embryonic fibroblast NIH3T3 cells, the cytotoxicity, cytocompatibility, and cell proliferation characteristics of LEV@ZIF-8 were evaluated in vitro. LEV@ZIF-8 composite considerably improved the biocompatibility against NIH3T3 cells after 72-h of exposure, according to in vitro experiments. Under acidic circumstances, the pH-responsive drug release studies exhibit superior LEV release, and in physiological circumstances, there is no unintended drug release. The LEV@ZIF-8 composite-treated cells demonstrate the most remarkable cell growth and migration method in a very short time, according to the results of the wound scratch experiment. The composite exposure concentration depended on inhibition against various microorganisms in the antibacterial activity testing. According to the study, LEV@ZIF-8 are appropriate and effective DDS for stimuli-based pediatric abdominal wound repair.

Fabrication and characterization of sodium alginate/blueberry anthocyanins/hinokitiol loaded ZIF-8 nanoparticles composite films with antibacterial activity for monitoring pork freshness

A smart film was developed to detect the freshness of pork by incorporating blueberry anthocyanins (BAs) and hinokitiol (HIN) loaded zeolite-imidazolium framework (HIN@ZIF-8) with into a sodium alginate matrix, and its microstructure and physicochemical properties were studied. The SA matrix was doped with BAs and HIN@ZIF-8 nanoparticles (SA-BAs/HIN@ZIF-8) to increase its tensile strength and reduce its water vapor permeability. HIN@ZIF-8 has low cytotoxicity, and SA-BAs/HIN@ZIF-8 membranes have long-lasting antimicrobial and highly sensitive color development properties against Escherichia coli and Staphylococcus aureus. The results of pork preservation experiments showed that SA-BA/HIN@ZIF-8 could extend the shelf life of pork to 6 days at 4 ℃. E-nose evaluation experiments showed that SA-BAs/HIN@ZIF-8 could inhibit compounds that cause unpleasant and irritating odours. Therefore, SA-BAs/HIN@ZIF-8 was considered to be an effective method to improve the freshness of pork, and the results showed that it has a promising application in food preservation.

Thymosin beta 10 loaded ZIF-8/sericin hydrogel promoting angiogenesis and osteogenesis for bone regeneration

Angiogenesis is pivotal for osteogenesis during bone regeneration. A hydrogel that promotes both angiogenesis and osteogenesis is essential in bone tissue engineering. However, creating scaffolds with the ideal balance of biodegradability, osteogenic, and angiogenic properties poses a challenge. Thymosin beta 10 (TMSB10), known for its dual role in angiogenesis and osteogenesis differentiation, faces limitations due to protein activity preservation. To tackle this issue, ZIF-8 was engineered as a carrier for TMSB10 (TMSB10@ZIF-8), and subsequently integrated into the self-assembled sericin hydrogel. The efficacy of the composite hydrogel in bone repair was assessed using a rat cranial defect model. Characterization of the nanocomposites confirmed the successful synthesis of TMSB10@ZIF-8, with a TMSB10 encapsulation efficiency of 88.21 %. The sustained release of TMSB10 from TMSB10@ZIF-8 has significantly enhanced tube formation in human umbilical vein endothelial cells (HUVECs) in vitro and promoted angiogenesis in the chicken chorioallantoic membrane (CAM) model in vivo. It has markedly improved the osteogenic differentiation ability of MC 3 T3-E1 cells in vitro. 8 weeks post-implantation, the TMSB10@ZIF-8/ Sericin hydrogel group exhibited significant bone healing (86.77 ± 8.91 %), outperforming controls. Thus, the TMSB10@ZIF-8/Sericin hydrogel, leveraging ZIF-8 for TMSB10 delivery, emerges as a promising bone regeneration scaffold with substantial clinical application potential.

3D-printing of alginate/gelatin scaffold loading tannic acid@ZIF-8 for wound healing: In vitro and in vivo studies

In the present study, ZIF-8 metal-organic framework (MOF) modified with Tannic acid (TA@ZIF-8) was synthesized and impregnated in alginate-gelatin (Alg-Gel) hydrogel. The Alg-Gel scaffolds containing 0, 5, and 10 % of TA@ZIF-8 were fabricated through the 3D printing method specifically denoted as Alg-Gel 0 %, Alg-Gel 5 %, and Alg-Gel 10 %. XRD, FTIR, FESEM, and EDX physically and chemically characterized the synthesized ZIF-8 and TA@ZIF-8 MOFs. Besides, Alg-Gel containing TA@ZIF-8 prepared scaffolds and their biological activity were also evaluated. SEM images verified the nano-size formation of MOFs. Improved swelling and decreased degradation rates after adding TA@ZIF-8 were also reported. Increased compression strength from 0.628 to 1.63 MPa in Alg-Gel 0 % and Alg-Gel 10 %, respectively, and a 2.19 increase in elastic modulus in Alg-Gel 10 % scaffolds were exhibited. Biological activity of scaffolds, including Live-dead and Cell adhesion, antibacterial, in-vivo, and immunohistochemistry assays, demonstrated desirable fibroblast cell proliferation and adhesion, increased bacterial growth inhibition zone, accelerated wound closure and improved expression of anti-inflammatory cytokines in Alg-Gel 10 % scaffolds. The findings of this study confirm that Alg-Gel 10 % scaffolds promote full-thickness wound healing and could be considered a potential candidate for full-thickness wound treatment purposes.

Polyvinylpyrrolidone/chitosan-loaded dihydromyricetin-based nanofiber membrane promotes diabetic wound healing by anti-inflammatory and regulating autophagy-associated protein expression

The healing of wounds in diabetics is commonly delayed by recurring infections and persistent inflammation at the wound site. For this reason, we conducted a study using the electrospinning technique to create nanofiber membranes consisting of polyvinylpyrrolidone/chitosan (PVP/CS) and incorporated dihydromyricetin (DHM) into them. Infrared Fourier transform spectroscopy and scanning electron microscopy were used to analyze the nanofiber membrane. Experimental results in vitro have shown that PVP/CS/DHM has exceptional properties such as hydrophilicity, porosity, water vapor transport rate, antioxidant capacity, and antibacterial activity. Moreover, our study has demonstrated that the application of PVP/CS/DHM can significantly improve wound healing in diabetic mice. After an 18-day treatment period, a remarkable wound closure rate of 88.63 ± 1.37 % was achieved. The in vivo experiments revealed that PVP/CS/DHM can promote diabetic wound healing by suppressing the activation of TLR4/MyD88/NF-κB signaling pathway and enhancing autophagy-related protein as well as CD31 and HIF-1α expression in skin tissues. This study showed that PVP/CS/DHM is a promising wound dressing.

Durable and recyclable MOF@polycaprolactone mixed-matrix membranes with hierarchical porosity for wastewater treatment

With the fast-growing global water crisis, the development of novel technologies for water remediation and reuse is crucial. Industrial wastewater especially contains various toxic pollutants that pose an additional threat to the environment; thus, efficient removal of such contaminants can ensure safe reprocessing of industrial wastewater, thereby alleviating the demand for fresh water. Herein, we describe a novel and efficient approach for preparing porous polycaprolactone (PCL) membranes with a hierarchical architecture via a simple solvent/non-solvent methodology. A mixed-matrix membrane (MMM) was further constructed utilizing an amine-functionalized metal-organic framework as the sorbent filler nanoparticles and PCL as the polymer support matrix (MOF@PCL) for wastewater treatment applications. The MOF@PCL MMM demonstrated homogeneous morphology as well as exceptional performance towards the removal of both cationic (methylene blue, MB) and anionic (methyl orange, MO) organic dyes, where the maximum adsorption capacities reached 309 mg g-1 and 208 mg g-1, respectively. Kinetic and thermodynamic investigations revealed that the adsorption process was endothermic with a fast intraparticle diffusion rate constant. The MOF@PCL MMM also displayed excellent mechanical stability and recyclability, where the removal efficiency was maintained after 10 cycles.

Matricaria chamomilla essential oil-loaded hybrid electrospun nanofibers based on polycaprolactone/sulfonated chitosan/ZIF-8 nanoparticles for wound healing acceleration

Recently, developing antibacterial wound dressings based on biomaterials display good biocompatibility and the potential to accelerate wound healing. For this aim, we prepared eco-friendly and biodegradable nanofibers (NFs) based on N-(3-sulfopropyl)chitosan/ poly (ε-caprolactone) incorporated by zeolite imidazolate framework-8 nanoparticles (ZIF-8 NPs) and chamomile essential oil (MCEO) via the electrospinning technique for their efficacy as wound dressing scaffolds. Fabricated NFs were characterized and studied for their structural, morphological, mechanical, hydrophilic, and thermal stability properties. The results of scanning electron microscopy (SEM) revealed that adding the ZIF-8 NPs/ MCEO, very slightly influenced the average diameter of NFs (PCL/SPCS (90:10) with 90 ± 32 nm). The developed uniform MCEO-loaded ZIF-8/PCL/SPCS NFs displayed better cytocompatibility, proliferation, and physicochemical properties (e.g. thermal stability and mechanical properties) than neat NFs. The results of cytocompatibility, DAPI (4',6-diamidino-2-phenylindole) staining study, and SEM micrographs demonstrated that formulated NFs had promising adhesion and proliferation against normal human foreskin fibroblasts-2 (HFF-2 cell line). The prepared NFs revealed excellent antibacterial activity against both Staphylococcus aureus and Escherichia coli with inhibition of 32.3 mm and 31.2 mm, respectively. Accordingly, the newly developed antibacterial NFs hold great potential as effective biomaterials for use as an active platform in wound healing applications.

Fabrication and characterization of waste fish scale-derived gelatin/sodium alginate/carvacrol loaded ZIF-8 nanoparticles composite films with sustained antibacterial activity for active food packaging

An environmental-friendly composite films containing waste fish scale-derived gelatin (FSG), sodium alginate (SA) and carvacrol loaded ZIF-8 (CV@ZIF-8) nanoparticles were designed and fabricated to develop active food packaging materials capable of sustained antibacterial activity. The microstructure and physicochemical properties of the FSG/SA/CV@ZIF-8 composite films were investigated. The incorporation of CV@ZIF-8 into FSG/SA matrix significantly enhanced the UV-light blocking and the elongation at break, improved water resistance and reduced water vapor permeability, and improved the thermal stability of composite film. The FSG/SA/CV@ZIF-8 film not only exhibited strong antioxidant activity with DPPH radical scavenging rate of 92.35 %, but also showed the satisfactory and long-acting antibacterial ability against E. coli and S. aureus due to slow release of CV from composite film. Strawberry preservation experiment revealed that FSG/SA/CV@ZIF-8 film decelerated the texture deterioration and retarded the growth of spoilage microorganism, resulting in the prolonged shelf-life of 8 days under ambient condition, indicating its promising application prospect in food preservation packaging.

The preparation of ultrathin and porous electrospinning membranes of HKUST-1/PLA with good antibacterial and filtration performances

Developing degradable filter membranes that inhibit bacterial infection for preventing particle matter and infectious disease has been a research hotspot. Here, the fiber membranes of polylactic acid (PLA)/HKUST-1 with porous structure through the entire fiber matrix were prepared by electrospinning method. Due to the HKUST-1 incorporation and the presence of pore through fiber, the hydrophobicity of prepared membranes had been improved. The PLA/HKUST-1 membranes exhibited the good antibacterial activity against Escherichia coli and Staphylococcus aureus , and the antibacterial rate for S. aureus reached 99.99%. The filtration performance of PLA/HKUST-1 membranes was better than that of the melt-blown fabric although their thickness was only about one-third of the thickness of the currently commercial polypropylene melt-blown fabric.

Zeolitic Imidazolate Framework-8 with Encapsulated Naringin Synergistically Improves Antibacterial and Osteogenic Properties of Ti Implants for Osseointegration

Titanium (Ti)-based implants are widely utilized in artificial joints, pedicle screws, and dental implantations due to their excellent biocompatibility, near perfect mechanical capacities, and strong corrosion resistance. However, the Ti substrates are bioinert and lack desirable antibacterial abilities, severely hindering their bone regeneration applications. Herein, the titania nanotubes (TNTs) are fabricated onto the Ti surfaces through anodic oxidation. They are then modified with naringin (Nar)-loaded zeolitic imidazolate framework-8 (ZIF-8) in order to obtain a multifunctional coating (TNT-ZIF-8@Nar) via hydrothermal treatment. The TNT-ZIF-8@Nar exhibits excellent pH-responsive properties and a strong antimicrobial effect against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) by releasing Zn²⁺ and Nar. TNT-ZIF-8@Nar coatings significantly enhance the proliferation and osteogenic differentiation of osteoblasts. Furthermore, in vivo studies demonstrated the efficacy of TNT-ZIF-8@Nar coatings in improving osseointegration and antibacterial capabilities. This work shows the promising therapeutic potential of TNT-ZIF-8@Nar in its ability to inhibit implant-associated infections and achieve favorable osseointegration simultaneously.

Designing of robust and sensitive assay via encapsulation of highly emissive and stable blue copper nanocluster into zeolitic imidazole framework (ZIF-8) with quantitative detection of tetracycline

Metal–organic frameworks (MOFs) with high stability and porosity have gained great attention in bioanalysis due to their potential in improving sensitivity and robustness of assays. Herein, to improve both the stability and the emission intensity of Cu nanoclusters (CuNCs), in situ entrapment strategy of CuNCs into zeolitic imidazolate framework-8 (ZIF-8) is described. Blue emissive and stable CuNCs was prepared, for the first time, using thiamine hydrochloride as capping agents, and showed strong and stable emission at 440 nm when excited at 375 nm with fluorescence quantum yields 12%. Encapsulation of CuNC into ZIF-8 showed dramatic enhancement of the fluorescence intensity up to 53% fluorescence quantum yield. Furthermore, the CuNCs@ZIF-8 possesses better stability (more than three months) due to protective and confinement effect of MOFs. Upon the addition of tetracycline to CuNCs@ZIF-8 solution, the blue emission intensity was significantly decreased. The fluorescence ratio (Fo/F) against the concentration of tetracycline exhibited a satisfactory linear relationship from 1.0 to 10.0 µM with a detection limit (LOD) of 0.30 µM. The current probe was applied for quantification of tetracycline in drug sample with satisfactory accuracy and precision.

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Preparation and characterization of Pullulan-based nanocomposite scaffold incorporating Ag-Silica Janus particles for bone tissue engineering

A nanocomposite bone scaffold was fabricated from pullulan, a natural extracellular polysaccharide. Pullulan (PULL) was blended with polyvinylpyrrolidone (PVP), and a nano-platform with ball-stick morphology, Ag-Silica Janus particles (Ag-Silica JPs), which were utilized to fabricate nanocomposite scaffold with enhanced mechanical and biological properties. The Ag-Silica JPs were synthesized via a one-step sol-gel method and used to obtain synergistic properties of silver and silica's antibacterial and bioactive effects, respectively. The synthesized Ag-Silica JPs were characterized by means of FE-SEM, DLS, and EDS. The PULL/PVP scaffolds containing Ag-Silica JPs, fabricated by the freeze-drying method, were evaluated by SEM, EDS, FTIR, XRD, ICP and biological analysis, including antibacterial activity, bioactivity, cell viability and cell culture tests. It was noted that increasing Ag-Silica JPs amounts to an optimum level (1% w/w) led to an improvement in compressive modulus and strength of nanocomposite scaffold, reaching 1.03 ± 0.48 MPa and 3.27 ± 0.18, respectively. Scaffolds incorporating Ag-Silica JPs also showed favorable antibacterial activity. The investigations through apatite forming ability of scaffolds in SBF indicated spherical apatite precipitates. Furthermore, the cell viability test proved the outstanding biocompatibility of nanocomposite scaffolds (more than 90%) confirmed by cell culture tests showing that increment of Ag-Silica JPs amounts led to better adhesion, proliferation, ALP activity and mineralization of MG-63 cells.

Sprayable methacrylic anhydride-modified gelatin hydrogel combined with bionic neutrophils nanoparticles for scar-free wound healing of diabetes mellitus

Hard-to-healing or nonhealing diabetic wounds caused by hyperglycemia, bacterial infection and chronic inflammation are becoming a challenge globally. In this study, a novel hydrogel for diabetic wound healing composed of methacrylic anhydride-modified gelatin (GelMA) hydrogel and mimicking neutrophil nanoparticles was originally created. The prepared GelMA hydrogel has good sprayability and film-formation ability under blue light illumination (wavelength = 435-480 nm). Nanoparticles mimicking neutrophils belong to a double enzyme system that are encapsulated in ZIF-8 nanoparticles, which can consume glucose to produce HClO, ensuring a decrease in the glucose concentration of the wound and growth inhibition in bacteria. The hydrogel also has excellent biocompatibility, which can promote the growth and proliferation of fibroblasts. More importantly, the hydrogel can accelerate wound healing in type I diabetic rats owing to the downregulation of proinflammatory cytokines, and the wound with an area of 1 cm² can be almost fully healed with no formation of the scar on the 21st day, as verified by histochemistry and immunohistochemistry. All these combinations indicate its potential in diabetic wound treatment.

MOF-Embedded Bifunctional Composite Nanofiber Membranes with a Tunable Hierarchical Structure for High-Efficiency PM0.3 Purification and Oil/Water Separation

Herein, a unique hierarchically structured composite nanofiber membrane, consisting of a zeolitic imidazolate framework-8-embedded polyethersulfone (PES@ZIF8) fiber layer and a polysulfonamide/polyethersulfone (PSA/PES) fiber layer, was successfully developed to cope with the complex environments during the actual filtration/separation process and overcome the conflict between high filtration efficiency and low air pressure resistance. Due to the advantages of the synergistic effect of multicomponents and the bi-layer hierarchical structure, the integrated PES@ZIF8-PSA/PES filter possesses an extremely high air filtration efficiency (up to 99.986%) under a very low pressure drop (only 15 Pa), superior PM_0.3 purification capacity (close to 99.95%), long-term recycling ability for purifying real smoke PM_2.5 from >800 to <10 μg/m³, extremely high temperature resistance (exceed 200 °C), flame retardancy, good chemical stability, satisfactory transmittance, and robust self-cleaning ability. Apart from these, it achieves effective separation of oil-water mixtures and oil-water emulsions as a result of selective wettability including hydrophobicity and superoleophilicity. In particular, the PES@ZIF8-PSA/PES nanofiber membranes maintain outstanding air filtration and oil/water separation properties under the high temperature or strong acid/alkali conditions. This special comprehensive performance gives the PES@ZIF8-PSA/PES-based filtration/separation membranes a wider application prospect ranging from environmental governance to individual protection and industrial security.

Manufacture of non-thrombogenic polymer surfaces by gamma irradiation to induce simultaneous grafting and heparinization of thin PVC films

Investigations regarding alternative methods for producing polymeric materials with hydrophilic properties have increased considerably. In this context, polymeric biomaterials with hemocompatible surface properties have been successfully obtained by grafting hydrophilic monomers onto commercial polymer films by simultaneous irradiation processes. In this study, simultaneous irradiation and grafting were used to produce a copolymer PVC-co-DMAEMA-co-heparin with hemocompatible surface properties. Characterization by FTIR of the graft copolymer indicates that the increase in monomer grafting levels inhibits the bonding sites to heparin. FTIR-PAS analyses of the graft copolymers showed that the highest graft levels were obtained for the irradiated samples containing 45% of monomer. Heparin, however, could only be detected in the irradiated samples containing 30% of DMAEMA. The analysis of the micrographs, on the other hand, showed that increasing the monomer concentration enhances surface roughness of the graft copolymers. Roughness however decreased with heparin addition. It was possible to verify that an excess of surface roughness of the graft copolymers inhibits anticoagulant properties of heparin, triggering thrombus formation. Platelet adhesion, on its turn, was not significantly affected by the presence of heparin when PVC-co-DMAEMA and PVC-co-DMAEMA-co-heparin, obtained from the systems containing 45% of monomer, are compared. The addition of heparin in the systems containing 30% of DMAEMA resulted in fewer thrombogenic surfaces.

An aqueous-based process to bioactivate poly(ε-caprolactone)/mesoporous bioglass composite surfaces by prebiotic chemistry-inspired polymer coatings for biomedical applications

Despite the wide use of aliphatic polyesters, such as poly(L-lactic acid) (PLLA) and poly(ε-caprolactone) (PCL), for many biomedical applications, these materials are limited due to their hydrophobic properties and lack of functional groups to bond with ligands to enhance the cell reorganization. Recently, a composite consisting of bioglass and PCL was demonstrated to enhance the mechanical strength and to improve the degradation rate. Although numerous approaches have been developed to improve the wettability of aliphatic polyesters to create a favorable interface with cells, only few surface modification methods can be independently applied to surfaces with different material. In this work, mesoporous bioglass (MBG) nanoparticles embedded in PCL films were modified by the polymerization of aminomalonitrile (AMN) with 3,4,5-trihydroxybenzaldehyde (THBA). The copolymer layer was further utilized as a mediator to conjugate chitosan and evaluate the antibacterial efficacy. Our results show that the hydrophilicity of the composite membranes significantly improved after treatment. In addition, after immersion in simulated body fluid (SBF) for 14 days, hydroxyapatite formation was only observed on the treated membranes. This result demonstrates that the surface treatment did not alter the MBG bioactivity. Moreover, the cell culture results reveal that the extension level of cells and expression of alkaline phosphatase activity (ALP) of osteoblast-like (MG63) cells were higher on treated composite films compared to untreated ones. The results imply that the treatment procedure can be simultaneously and homogeneously applied to the organic/inorganic composites. In addition, Staphylococcus aureus adhesion on AMN-co-THBA and chitosan/ AMN-co-THBA was significantly lower than untreated PCL. Moreover, the percentage of dead bacteria was highest on the chitosan/ AMN-co-THBA membranes. These results indicate that the AMN-co-THBA modification can be used in composite materials and complex constructs, and it provides a potential method to create versatile surface properties for biomedical applications.

Janus membranes for membrane distillation: Recent advances and challenges

Membrane distillation (MD) is a promising hybrid thermal-membrane separation technology that can efficiently produce freshwater from seawater or contaminated wastewater. However, the relatively low flux and the presence of fouling or wetting agents in feed solution negate the applicability of MD for long term operation. In recent years, 'two-faced' membranes or Janus membranes have shown promising potential to decrease wetting and fouling problem of common MD system as well as enhance the flux performance. In this review, a comprehensive study was performed to investigate the various fabrication, modification, and novel design processes to prepare Janus membranes and discuss their performance in desalination and wastewater treatment utilizing MD. The promising potential, challenges and future prospects relating to the design and use of Janus membranes for MD are also tackled in this review.

A review on surface modification methods of poly(arylsulfone) membranes for biomedical applications

Considerable methods have so far been used for the surface modification of biomedical membranes. Several reviews and articles have been published on the improvements achieved in the field of poly(arylsulfone) membranes subjected to various surface modification methods and used in biomedical applications. This review concentrates on the surface modification, biological applications and future perspective of the poly(arylsulfone) biomedical membranes. Different surface modification procedures employed for the poly(arylsulfone) membranes have been classified, studied and compared. Diverse surface modification techniques include surface coating, chemical modification and immobilization/cross-linking, grafting, surface zwitterionicalization, mussel-inspired coating and layer-by-layer assembly. Furthermore, we review the recent research studies performed on the surface modification of the poly(arylsulfone) biomedical membranes. Meanwhile, the properties of biomedical membranes are also discussed in each section. At last, the future perspective and challenges of the strategies utilized for the surface modification of poly(arylsulfone) biomedical membranes are presented.

Electrospun pectin/modified copper-based metal-organic framework (MOF) nanofibers as a drug delivery system

Pectin has been regarded as a drug carrier accelerating the healing process due to its bioactivities, abundance and lower cost of resources. However, a big challenge related to its practical application is its poor mechanical strength. In this study the modified Cu-based MOF containing Folic acid was synthesized and incorporated in the suitable pectin electrospun nanofibers which not only improved the copper ions release behavior but also made the fiber mat stronger, antibacterial and induce angiogenesis, fibroblast migration, and proliferation due to loaded copper ions and folic acid. The nanofibers composing of 75% pectin and 4000 kDa -PEO were chosen after morphological and mechanical characterization. Finally, the effect of MOF incorporation on the nanocomposite samples was characterized in terms of morphological, physiochemical and biological properties. The nanofibrous mats were evaluated by tensile testing, antibacterial and cytotoxicity. The release behavior of copper ions and folic acid was controlled and their burst release alleviated reducing cytotoxicity in vitro. It was found that the Young's moduli of the pectin nanofibers were improved to 19.13 MPa by the addition of Cu-based MOFs. Moreover, nanocomposite pectin nanofibers were found to be antibacterial and biocompatible. These results demonstrate that MOF-contained pectin nanofibers are promising for biomedical applications.

Silk fibroin/poly-(L-lactide-co-caprolactone) nanofiber scaffolds loaded with Huangbai Liniment to accelerate diabetic wound healing

Diabetic infection is a long-term complication difficult to cure. The skin of diabetic patients is prone to damage, the healing is slow after the injury, and the wound occurs repeatedly. Therefore, there is an urgent need to develop an effective method for treating diabetes wounds. In this study, we used the electrospinning technique to load Huangbai Liniment (Compound Phellodendron Liquid, CPL) into Silk fibroin (SF) /poly-(L-lactide-co-caprolactone) (PLCL) to prepare the nanofiber membrane (SP/CPL) to treat the diabetic wound. The morphology and structure of the nanofibers were observed by scanning electron microscope (SEM). The SEM results indicate the smooth and bead free fibers and the diameter of the fiber decreased with increasing drug concentration. The release profile indicates the sustained release of the drug. Moreover, the drug-loaded nanofibers showed inhibitory effects for S.aureus and E.coli. Furthermore, in vitro cell culture studies showed the increased proliferation and adhesion of NIH-3T3 cells on the drug-containing nanofiber membrane. Animal experiments showed that the nanofiber membrane loaded with CPL increases the expression of the TGF-β signaling pathway and collagen during wound healing, inhibits the expression of pro-inflammatory factors, and thus effectively promotes wound healing in diabetic mice. Therefore, the SP/CPL nanofiber scaffold with CPL loading is a potential candidate for diabetic wound dressings and tissue engineering.

Recent trends on wound management: New therapeutic choices based on polymeric carriers

Wound healing is an unmet therapeutic challenge among medical society since wound assessment and management is a complex procedure including several factors playing major role in healing process. Wounds can mainly be categorized as acute or chronic. It is well referred that the acute wound displays normal wound physiology while healing, in most cases, is seemed to progress through the normal phases of wound healing. On the other hand, a chronic wound is physiologically impaired. The main problem in wound management is that the majority of wounds are colonized with microbes, whereas this does not mean that all wounds will be infected. In this review, we address the problems that clinicians face to manage while treat acute and chronic wounds. Moreover, we demonstrate the pathophysiology, etiology, prognosis and microbiology of wounds. We further introduce the state of art in pharmaceutical technology field as part of wound management aiming to assist health professionals to overcome the current implications on wound assessment. In addition, authors review researches which included the use of gels and dermal films as wound healing agents. It can be said that natural and synthetic drugs or carriers provide promising solutions in order to meet the wound management standards. However, are the current strategies as desirable as medical society wish?

Fabrication of chitosan-polyethylene glycol nanocomposite films containing ZIF-8 nanoparticles for application as wound dressing materials

Biocompatible nanocomposite films based on chitosan (CS) and polyethylene glycol (PEG) polymers containing cephalexin (CFX) antibiotic drug and zeolitic imidazolate framework-8 (ZIF-8) nanoparticles (NPs) were designed and fabricated to develop wound dressing materials capable of controlled drug release. Swelling experiment was performed in three acidic, neutral, and alkaline solutions. The tensile strength test reflected that upon increasing the NPs loading within the films, the tensile strength was enhanced but the elongation at break was diminished. The release of the CFX was intensively increased within approximately 3, 8, and 10 h (burst release) in acidic, neutral, and alkaline media, respectively while after that the CFX was smoothly released over time (sustained release). The antibacterial activities of all films were examined against Gram-positive (S. aureus, B. cereus) and Gram-negative (E. coli, P. aeruginosa, and Acinetobacter) bacteria frequently found in the infected wounds. Moreover, the MTT assay revealed that all films had high cell viabilities towards the L929 fibroblast cells confirming these nanocomposites could be used as favorable wound dressing materials. Finally, the film containing 4% ZIF-8 NPs (film 5) was chosen as the best sample due to it revealed appropriate mechanical properties, swelling, drug release and cell viability among all samples examined.

Synthesis and modification of ZIF-8 and its application in drug delivery and tumor therapy

Metal–organic frameworks have the properties of high porosity, variable pore sizes, and easy modification as drug delivery systems. In particular, ZIF-8 based on Zn²⁺ has been extensively studied in the medical field due to its low toxicity and good biocompatibility. This review introduces the preparation and functional modification of ZIF-8, and its application in drug delivery, focusing on the single-stimulus and multi-stimulus response release of drugs in ZIF-8 materials, the integrated role of diagnosis and treatment with ZIF-8 in cancer treatment, and its application in the synergistic therapy of multiple cancer treatment methods. We summarize the latest developments of ZIF-8 in the field of drug delivery and tumor therapy, and present the main challenges that remain to be resolved in the ZIF-8 drug delivery system.

Synthesis and modification of ZIF-8 and its application in drug delivery, stimulus response-controlled drug release and tumor therapy.

Polyvinylidene fluoride-Hyaluronic acid wound dressing comprised of ionic liquids for controlled drug delivery and dual therapeutic behavior

To improve the efficacy of transdermal drug delivery systems, the physical and chemical properties of drugs need to be optimized to better penetrate into the stratum corneum and to better diffuse into the epidermis and dermis layers. Accordingly, dual-biological function ionic liquids composed of active pharmaceutical ingredients were synthesized, comprising both analgesic and anti-inflammatory properties, by combining a cation derived from lidocaine and anions derived from hydrophobic nonsteroidal anti-inflammatory drugs. Active pharmaceutical ingredient ionic liquids (API-ILs) were characterized through nuclear magnetic resonance, cytotoxicity assay, and water solubility assay. All properties were compared with those of the original drugs. By converting the analgesic and anti-inflammatory drugs into dual-function API-ILs, their water solubility increased up to 470-fold, without affecting their cytotoxic profile. These API-ILs were incorporated into a bilayer wound dressing composed of a hydrophobic polyvinylidene fluoride (PVDF) membrane to act as a drug reservoir and a biocompatible hyaluronic acid (HA) layer. The prepared bilayer wound dressing was characterized in terms of mechanical properties, membrane drug uptake and drug release behavior, and application in transdermal delivery, demonstrating to have desirable mechanical properties and improved release of API-ILs. The assessment of anti-inflammatory activity through the inhibition of LPS-induced production of nitric oxide and prostaglandin E2 by macrophages revealed that the prepared membranes containing API-ILs are as effective as those with the original drugs. Cell adhesion of fibroblasts on membrane surfaces and cell viability assay confirmed improved the viability and adhesion of fibroblasts on PVDF/HA membranes. Finally, wound healing assay performed with fibroblasts showed that the bilayer membranes containing dual-function API-ILs are not detrimental to wound healing, while displaying increased and controlled drug delivery and dual therapeutic behavior. STATEMENT OF SIGNIFICANCE: This work shows the preparation and characterization of bilayer wound dressings comprising dual-biological function active pharmaceutical ingredients based on ionic liquids with improved and controlled drug release and dual therapeutic efficiency. By converting analgesic and anti-inflammatory drugs into ionic liquids, their water solubility increases up to 470-fold. The prepared bilayer wound dressing membranes have desirable mechanical properties and improved release of drugs. The prepared membranes comprising ionic liquids display anti-inflammatory activity as effective as those with the original drugs. Cell adhesion of fibroblasts on membrane surfaces and cell viability assays show improved viability and adhesion of fibroblasts on PVDF/HA membranes, being thus of high relevance as effective transdermal drug delivery systems.