Novel zinc-silver nanocages for drug delivery and wound healing: Preparation, characterization and antimicrobial activities

Fast skin healing chitosan/PEO hydrogels: In vitro and in vivo studies

Due to its outstanding qualities, particularly when it takes the shape of hydrogels, chitosan is a well-known biological macromolecule with many applications. When chitosan hydrogels are modified with other polymers, the desirable function as skin regeneration hydrogels is compromised; nevertheless, the mechanical properties can be improved, which is crucial for commercialization. In this study, for the first time, bimetallic zinc silver metal-organic frameworks (ZAg MOF) loaded with ascorbic acid were added to chitosan/polyethylene oxide (PEO) based interpenetrating polymer network (IPN) hydrogels that were crosslinked with biotin to improve their antimicrobial activity, mechanical characteristics, and sustainable treatment of wounds. Significant changes in the microstructure, hydrophilicity level, and mechanical properties were noticed. Ascorbic acid release patterns were upregulated in an acidic environment pH (5.5) that mimics the initial wound pH. Impressive cell viability (98 %), antimicrobial properties, and almost full skin healing in a short time were achieved for the non-replaceable chitosan/PEO developed hydrogels. Enhancing the wound healing of the treated animals using the prepared CS/PEO hydrogel dressing was found to be a result of the inhibition of dermal inflammation via decreasing IL-1β, suppressing ECM degradation (MMP9), stimulating proliferation through upregulation of TGF-β and increasing ECM synthesis as it elevates collagen 1 and α-SMA contents. The findings support the implementation of developed hydrogels as antimicrobial hydrogels dressing for fast skin regeneration.

MOFs and MOF-Based Composites as Next-Generation Materials for Wound Healing and Dressings

In recent years, there has been growing interest in developing innovative materials and therapeutic strategies to enhance wound healing outcomes, especially for chronic wounds and antimicrobial resistance. Metal-organic frameworks (MOFs) represent a promising class of materials for next-generation wound healing and dressings. Their high surface area, pore structures, stimuli-responsiveness, antibacterial properties, biocompatibility, and potential for combination therapies make them suitable for complex wound care challenges. MOF-based composites promote cell proliferation, angiogenesis, and matrix synthesis, acting as carriers for bioactive molecules and promoting tissue regeneration. They also have stimuli-responsivity, enabling photothermal therapies for skin cancer and infections. Herein, a critical analysis of the current state of research on MOFs and MOF-based composites for wound healing and dressings is provided, offering valuable insights into the potential applications, challenges, and future directions in this field. This literature review has targeted the multifunctionality nature of MOFs in wound-disease therapy and healing from different aspects and discussed the most recent advancements made in the field. In this context, the potential reader will find how the MOFs contributed to this field to yield more effective, functional, and innovative dressings and how they lead to the next generation of biomaterials for skin therapy and regeneration.

Application of metal-organic frameworks-based functional composite scaffolds in tissue engineering

With the rapid development of materials science and tissue engineering, a variety of biomaterials have been used to construct tissue engineering scaffolds. Due to the performance limitations of single materials, functional composite biomaterials have attracted great attention as tools to improve the effectiveness of biological scaffolds for tissue repair. In recent years, metal-organic frameworks (MOFs) have shown great promise for application in tissue engineering because of their high specific surface area, high porosity, high biocompatibility, appropriate environmental sensitivities and other advantages. This review introduces methods for the construction of MOFs-based functional composite scaffolds and describes the specific functions and mechanisms of MOFs in repairing damaged tissue. The latest MOFs-based functional composites and their applications in different tissues are discussed. Finally, the challenges and future prospects of using MOFs-based composites in tissue engineering are summarized. The aim of this review is to show the great potential of MOFs-based functional composite materials in the field of tissue engineering and to stimulate further innovation in this promising area.

Multicomponent decellularized extracellular matrix of caprine small intestine submucosa based bioactive hydrogel promoting full-thickness burn wound healing in rabbits

Effective treatment for full-thickness burn wounds has remained challenging for clinicians. Among various strategies, extracellular gel-based dressing materials have gained attention to promote effective and rapid wound healing. These gel-based materials are porous and have antioxidant, antibacterial, hydrophilic, biodegradation, and biocompatible properties and hence can be used to alleviate burn wound healing. In concurrence with these findings, the present study evaluates thermo-responsive and self-assembled decellularized extracellular matrix (ECM) of caprine small intestine submucosa (DG-SIS) gel-based dressing material for burn wound healing. To expedite healing and efficiently tackle excessive free radicals and bioburden at the burn wound site, DG-SIS gel is fortified with antibacterial components (zinc oxide nanoparticles; ZnO) and a potent antioxidant agent (Vitamin-C;Vt-C). ZnO- and Vt-C-enriched DG-SIS (DG-SIS/ZnO/Vt-C) gels significantly increased the antioxidant and antibacterial activity of the therapeutic hydrogel. Additionally, the fabricated DG-SIS/ZnO/Vt-C bioactive gel resulted in significant full-thickness burn wound contraction (97.75 % in 14 days), a lower inflammatory effect, and enhanced angiogenesis with the highest collagen synthesis (1.22 μg/mg in 14 days) at the wound site. The outcomes from this study demonstrate a synergistic effect of ZnO/Vt-C in the bioactive gel as an effective and inexpensive therapeutic approach for full-thickness burn wound treatment.

Cu-vitamin B3 donut-like MOFs incorporated into TEMPO-oxidized bacterial cellulose nanofibers for wound healing

In this study, a novel multifunctional nanocomposite wound dressing was developed, consisting of TEMPO-oxidized bacterial cellulose (TOBC) nanofibers functionalized with donut-like copper-based metal-organic frameworks (CuVB3 MOFs). These CuVB3 MOFs were constructed using copper nodes linked by vitamin B3 molecules, resulting in a copper nicotinate crystal structure as confirmed by X-ray diffraction. Electron microscopy confirmed the presence of donut-like microstructures with uniform element distribution in the synthesized MOFs. Through the incorporation of CuVB3 MOFs into the TOBC nanofibers, innovative TOBC-CuVB3 nanocomposites were created. Biocompatibility testing using the MTT assay demonstrated enhanced cell viability of over 115% for the TOBC-CuVB3 nanocomposite. Acridine Orange staining revealed a ratio of 88-92% live cells on the wound dressings. Furthermore, fibroblast cells cultured on TOBC-CuVB3 exhibited expanded morphologies with long filopodia. The agar diffusion method exhibited improved antibacterial activity against both Gram-positive and Gram-negative bacterial strains, correlating with increased CuVB3 concentration in the samples. In vitro cellular scratch assays demonstrated excellent wound healing potential, with a closure rate of over 98% for wounds treated with the TOBC-CuVB3 nanocomposite. These findings underscore the synergistic effects of copper, vitamin B3, and TOBC nanofibers in the wound healing process.

Biomolecular and cellular effects in skin wound healing: the association between ascorbic acid and hypoxia-induced factor

The skin serves as a barrier to protect the body from environmental microorganisms and is the largest tissue of the body and any damage must be quickly and effectively repaired. The fundamental purpose of dermal fibroblasts is to produce and secrete extracellular matrix, which is crucial for healing wounds. The production of collagen by dermal fibroblasts requires the cofactor ascorbic acid, a free radical scavenger. In skin wounds, the presence of Ascorbic acid (AA) decreases the expression of pro-inflammatory factors and increases the expression of wound-healing factors. In addition, AA plays an important role in all three phases of wound healing, including inflammation, proliferation, and regeneration. On the other hand, growing evidence indicates that hypoxia improves the wound healing performance of mesenchymal stem cell-conditioned medium compared to the normoxic-conditioned medium. In a hypoxic-conditioned medium, the proliferation and migration of endothelial cells, fibroblasts, and keratinocytes (important cells in accelerating skin wound healing) increase. In this review, the role of AA, hypoxia, and their interactions on wound healing will be discussed and summarized by the in vitro and in vivo studies conducted to date.

Oriented ascorbic acid onto zeolitic metal-organic framework-8 membrane via microfluidic spinning for biomedical care

Nowadays, the hydrogen dressing and electrostatic spun films widely used on wounds do not facilitate the permeability of the wound area and fail to achieve controlled drug delivery. Therefore, finding a wound dressing with both breathability and targeted drug delivery has remained an unmet challenge. Here, an oriented microstructure membrane with sustained drug release and robust antibacterial performance was constructed through the microfluidic spinning method. The multifunctional oriented membrane was prepared by loading ascorbic acid onto the zeolitic metal-organic framework-8 to develop drug delivery nanomaterial zeolitic metal-organic framework-8 @ascorbic acid (ZIF-8 @AA) and then mixing ZIF-8 @AA with polyvinyl pyrrolidone (PVP) solution via microfluidic technology, which produced an oriented microfiber member. In addition, the spinning parameters, including the fluid content, rotation speed, and flow rate, on microfiber diameter were evaluated. The constructed oriented membrane had bactericidal efficiencies of 82.94% ± 2.79% and 95.96% ± 1.54% against E. coli and S. aureus, respectively. After five days, the membrane still has a sustained release. Moreover, the fabricated membrane also has good biocompatibility and hemocompatibility in vitro. The oriented arrangement strategy provides a promising approach for wound healing materials in targeted drug delivery. Furthermore, this strategy offers a feasible idea for loading active materials into substrates for disease treatment in the biomedical field.

Preparation and evaluation of a novel alginate-arginine-zinc ion hydrogel film for skin wound healing

In this paper, the mixed solution of sodium alginate (SA) and arginine (Arg) was dried into a film and then crosslinked with zinc ion to form sodium alginate-arginine-zinc ion (SA-Arg-Zn²⁺) hydrogel for skin wound dressings. SA-Arg-Zn²⁺ hydrogel had higher swelling ability, which was beneficial to absorbing wound exudate. Moreover, it exhibited antioxidant activity and strong inhibition against E. coli and S. aureus, and had no obvious cytotoxicity to NIH 3T3 fibroblasts. Compared with other dressings utilized in rat skin wound, SA-Arg-Zn²⁺ hydrogel showed better wound healing efficacy and the wound closure ratio reached to 100 % on the 14th day. The result of Elisa test indicated that SA-Arg-Zn²⁺ hydrogel down-regulated the expression of inflammatory factors (TNF-α and IL-6) and promoted the growth factor levels (VEGF and TGF-β₁). Furthermore, H&E staining results confirmed that SA-Arg-Zn²⁺ hydrogel could reduce wound inflammation and accelerate re-epithelialization, angiogenesis and wound healing. Therefore, SA-Arg-Zn²⁺ hydrogel is an effective and innovative wound dressing, moreover, the preparation technique is simple and feasible for industrial application.

Polyethylene glycol and chitosan functionalized manganese oxide nanoparticles for antimicrobial and anticancer activities

Biocompatible polymer-functionalized magnetic nanoparticles could offer promising applications in biomedical sciences. We fabricated polymer functionalized tri-manganese tetra oxide (Mn₃O₄) nanoparticles with the co-precipitation method and an octahedral crystal structure having a crystallite size of 10-17 nm was identified via XRD analyses. The SEM graph depicted the non-uniform and smooth surface of PEG-functionalized Mn₃O₄ NPs as compared to Mn₃O₄ and chitosan-coated Mn₃O₄ NPs. Elemental composition in the prepared sample was examined by EDX analysis. Various modes such as MnO, MnOH, OH, symmetric, and anti-symmetric of CH₂ attached to the spectrum of Mn₃O₄ NPs were observed with FTIR analysis. The magnetization factor decreased and increase the coreacivity and retentivity of surface functionalized Mn₃O₄-NPs was calculated via VSM analysis. In-vitro bioassay, antibacterial activity was tested against Escherichiacoli, Bacillus cereus, and anti-fungal activities against two Fusarium strains indicated clear antimicrobial activities. The MTT assay to examine the anticancer activity against the MCF-7 cancer cell line was performed and the T₁ MRI contrast agent demonstrated that PEG-coated Mn₃O₄ NPs exhibited anti-cancer activities. We propose that surface-functionalized magnetic NPs used for the treatment of cancer by using a remote controlled process of hyperthermia therapy.

Metal-Organic Frameworks and Their Biodegradable Composites for Controlled Delivery of Antimicrobial Drugs

Antimicrobial resistance (AMR) is a growing global crisis with an increasing number of untreatable or exceedingly difficult-to-treat bacterial infections, due to their growing resistance to existing drugs. It is predicted that AMR will be the leading cause of death by 2050. In addition to ongoing efforts on preventive strategies and infection control, there is ongoing research towards the development of novel vaccines, antimicrobial agents, and optimised diagnostic practices to address AMR. However, developing new therapeutic agents and medicines can be a lengthy process. Therefore, there is a parallel ongoing worldwide effort to develop materials for optimised drug delivery to improve efficacy and minimise AMR. Examples of such materials include functionalisation of surfaces so that they can become self-disinfecting or non-fouling, and the development of nanoparticles with promising antimicrobial properties attributed to their ability to damage numerous essential components of pathogens. A relatively new class of materials, metal-organic frameworks (MOFs), is also being investigated for their ability to act as carriers of antimicrobial agents, because of their ultrahigh porosity and modular structures, which can be engineered to control the delivery mechanism of loaded drugs. Biodegradable polymers have also been found to show promising applications as antimicrobial carriers; and, recently, several studies have been reported on delivery of antimicrobial drugs using composites of MOF and biodegradable polymers. This review article reflects on MOFs and polymer-MOF composites, as carriers and delivery agents of antimicrobial drugs, that have been studied recently, and provides an overview of the state of the art in this highly topical area of research.

Oil mediated green synthesis of nano silver in the presence of surfactants for catalytic and food preservation application

The present study details the green synthesis of silver nanoparticles using clove oil as a reducing and stabilizing agent. Cationic, anionic, nonionic and zwitterionic surfactants were introduced to study the change in size, shape, and morphology of nanoparticles. The nanoparticles were characterized using different techniques. The nanoparticles had shown specific surface Plasmon resonance band with absorbance between 380 and 385 nm. The X-ray diffraction study revealed that the nanoparticles are composed of spherical cubic crystals with average size between 136 and 180 nm while Dynamic Laser scattering (DLS) studies revealed an effective diameter of 82 nm and polydispersity index of 0.005. Thermogravimetric analysis suggested that the particles are stable even at 600 °C. All the samples presented good antibacterial and antifungal efficacies against Staphylococcus aureus, Klebsiella pneumonia and Candida albicans and good catalytic activities for the degradation of fast green and Allura red dyes. Further, thin edible films of the nanoparticles were prepared using sodium alginate for food preservation. The films were coated on fruits and vegetables for extending their shelf life to cope with demand and supply gap.

Application of Metal–Organic Framework in Diagnosis and Treatment of Diabetes

Diabetes-related chronic wounds are often accompanied by a poor wound-healing environment such as high glucose, recurrent infections, and inflammation, and standard wound treatments are fairly limited in their ability to heal these wounds. Metal–organic frameworks (MOFs) have been developed to improve therapeutic outcomes due to their ease of engineering, surface functionalization, and therapeutic properties. In this review, we summarize the different synthesis methods of MOFs and conduct a comprehensive review of the latest research progress of MOFs in the treatment of diabetes and its wounds. State-of-the-art in vivo oral hypoglycemic strategies and the in vitro diagnosis of diabetes are enumerated and different antimicrobial strategies (including physical contact, oxidative stress, photothermal, and related ions or ligands) and provascular strategies for the treatment of diabetic wounds are compared. It focuses on the connections and differences between different applications of MOFs as well as possible directions for improvement. Finally, the potential toxicity of MOFs is also an issue that we cannot ignore.