Micro Magnetic Field Produced by Fe3O4 Nanoparticles in Bone Scaffold for Enhancing Cellular Activity

Enhancing bone regeneration: Unleashing the potential of magnetic nanoparticles in a microtissue model

Bone tissue engineering addresses the limitations of autologous resources and the risk of allograft disease transmission in bone diseases. In this regard, engineered three-dimensional (3D) models emerge as biomimetic alternatives to natural tissues, replicating intracellular communication. Moreover, the unique properties of super-paramagnetic iron oxide nanoparticles (SPIONs) were shown to promote bone regeneration via enhanced osteogenesis and angiogenesis in bone models. This study aimed to investigate the effects of SPION on both osteogenesis and angiogenesis and characterized a co-culture of Human umbilical vein endothelial cells (HUVEC) and MG-63 cells as a model of bone microtissue. HUVECs: MG-63s with a ratio of 4:1 demonstrated the best results among other cell ratios, and 50 μg/mL of SPION was the optimum concentration for maximum survival, cell migration and mineralization. In addition, the data from gene expression illustrated that the expression of osteogenesis-related genes, including osteopontin, osteocalcin, alkaline phosphatase, and collagen-I, as well as the expression of the angiogenesis-related marker, CD-31, and the tube formation, is significantly elevated when the 50 μg/mL concentration of SPION is applied to the microtissue samples. SPION application in a designed 3D bone microtissue model involving a co-culture of osteoblast and endothelial cells resulted in increased expression of specific markers related to angiogenesis and osteogenesis. This includes the design of a novel biomimetic model to boost blood compatibility and biocompatibility of primary materials while promoting osteogenic activity in microtissue bone models. Moreover, this can improve interaction with surrounding tissues and broaden the knowledge to promote superior-performance implants, preventing device failure.

Fatigue Performance of 3D-Printed Poly-Lactic-Acid Bone Scaffolds with Triply Periodic Minimal Surface and Voronoi Pore Structures

Bone scaffolds serve a crucial role in tissue engineering, particularly in facilitating bone regeneration where natural repair is insufficient. Despite advancements in the fabrication of polymeric bone scaffolds, the challenge remains to optimize their mechanical resilience. Specifically, research on the fatigue behaviour of polymeric bone scaffolds is scarce. This study investigates the influence of pore architecture on the mechanical performance of poly-lactic-acid (PLA) scaffolds under quasi-static and cyclic compression. PLA scaffolds with a 60% porosity were fabricated using extrusion-based 3D printing in various designs: Gyroid, Lidinoid, Fischer-Koch, IWP, and Voronoi. Results demonstrated that Gyroid scaffolds had the highest compressive strength (6.6 MPa), followed by Lidinoid, Fischer-Koch, IWP, and Voronoi designs. Increased strut thickness was linked to higher compressive strength. However, normalized fatigue resistance showed a different pattern. While scaffolds resisted fatigue cycles at low strain amplitudes, fatigue damage was observed at higher strains. Voronoi structures exhibited the highest normalized fatigue performance, enduring around 58,000 cycles at 85% strain amplitude, followed by Gyroid, Fischer-Koch, Lidinoid, and IWP structures. Enhanced fatigue performance in different topologies correlated with the minimum cross-sectional area of scaffolds. Given the importance of both static and fatigue strength, the Gyroid topology emerges as the superior choice overall.

IKVAV functionalized oriented PCL/Fe3O4 scaffolds for magnetically modulating DRG growth behavior

The re-bridging of the deficient nerve is the main problem to be solved after the functional impairment of the peripheral nerve. In this study, a directionally aligned polycaprolactone/triiron tetraoxide (PCL/Fe3O4) fiber scaffolds were firstly prepared by electrospinning technique, and further then grafted with IKVAV peptide for regulating DRG growth and axon extension in peripheral nerve regeneration. The results showed that oriented aligned magnetic PCL/Fe3O4 composite scaffolds were successfully prepared by electrospinning technique and possessed good mechanical properties and magnetic responsiveness. The PCL/Fe3O4 scaffolds containing different Fe3O4 concentrations were free of cytotoxicity, indicating the good biocompatibility and low cytotoxicity of the scaffolds. The IKVAV-functionalized PCL/Fe3O4 scaffolds were able to guide and promote the directional extension of axons, the application of external magnetic field and the grafting of IKVAV peptides significantly further promoted the growth of DRGs and axons. The ELISA test results showed that the AP-10 F group scaffolds promoted the secretion of nerve growth factor (NGF) from DRG under a static magnetic field (SMF), thus promoting the growth and extension of axons. Importantly, the IKVAV-functionalized PCL/Fe3O4 scaffolds could significantly up-regulate the expression of Cntn2, PCNA, Sox10 and Isca1 genes related to adhesion, proliferation and magnetic receptor function under the stimulation of SMF. Therefore, IKVAV-functionalized PCL/Fe3O4 composite oriented scaffolds have potential applications in neural tissue engineering.

Current approaches in tissue engineering-based nanotherapeutics for osteosarcoma treatment

Osteosarcoma (OS) is a malignant bone neoplasm plagued by poor prognosis. Major treatment strategies include chemotherapy, radiotherapy, and surgery. Chemotherapy to treat OS has severe adverse effects due to systemic toxicity to healthy cells. A possible way to overcome the limitation is to utilize nanotechnology. Nanotherapeutics is an emerging approach in treating OS using nanoparticulate drug delivery systems. Surgical resection of OS leaves a critical bone defect requiring medical intervention. Recently, tissue engineered scaffolds have been reported to provide physical support to bone defects and aid multimodal treatment of OS. These scaffolds loaded with nanoparticulate delivery systems could also actively repress tumor growth and aid new bone formation. The rapid developments in nanotherapeutics and bone tissue engineering have paved the way for improved treatment efficacy for OS-related bone defects. This review focuses on current bifunctional nanomaterials-based tissue engineered (NTE) scaffolds that use novel approaches such as magnetic hyperthermia, photodynamic therapy, photothermal therapy, bioceramic and polymeric nanotherapeutics against OS. With further optimization and screening, NTE scaffolds could meet clinical applications for treating OS patients.

Investigation of background, novelty and recent advance of iron (II,III) oxide- loaded on 3D polymer based scaffolds as regenerative implant for bone tissue engineering: A review

Bone tissue engineering had crucial role in the bone defects regeneration, particularly when allograft and autograft procedures have limitations. In this regard, different types of scaffolds are used in tissue regeneration as fundamental tools. In recent years, magnetic scaffolds show promising applications in different biomedical applications (in vitro and in vivo). As superparamagnetic materials are widely considered to be among the most attractive biomaterials in tissue engineering, due to long-range stability and superior bioactivity, therefore, magnetic implants shows angiogenesis, osteoconduction, and osteoinduction features when they are combined with biomaterials. Furthermore, these scaffolds can be coupled with a magnetic field to enhance their regenerative potential. In addition, magnetic scaffolds can be composed of various combinations of magnetic biomaterials and polymers using different methods to improve the magnetic, biocompatibility, thermal, and mechanical properties of the scaffolds. This review article aims to explain the use of magnetic biomaterials such as iron (II,III) oxide (Fe2O3 and Fe3O4) in detail. So it will cover the research background of magnetic scaffolds, the novelty of using these magnetic implants in tissue engineering, and provides a future perspective on regenerative implants.

Efficient biodechlorination at the Fe3O4-based silicone powder modified chlorobenzene-affinity anode

The treatment of chlorinated volatile organic compounds faces challenges of secondary pollution and less-efficiency due to the substitution of chlorine. Microbial fuel cells (MFCs) provide a promising opportunity for its abatement. In this study, a novel Fe3O4 nanoparticles and silicone-based powder (SP) were integrated and immobilized on carbon felt (CF+Fe3O4@SP), which was further used as anode in the chlorobenzene (CB) powered MFC. Owing to the cooperation between SP and Fe3O4, the anode exhibited excellent performance for both biodechlorination and power generation. The results indicated that the CF+Fe3O4@SP anode loaded MFC achieved 98.5% removal of 200 mg/L CB within 28 h, and the maximum power density was 675.9 mW/m3, which was a 45.6% increase compared to that of the bare CF anode. Microbial community analysis indicated that the genera Comamonadaceae, Pandoraea, Obscuribacteraceae, and Truepera were dominated, especially, the Comamonadaceae and Obscuribacteraceae showed outstanding affinity for Fe3O4 and SP, respectively. Moreover, the proportion of live bacteria, secretion of extracellular polymer substances, and protein content in the extracellular polymer substances were significantly increased by modifying Fe3O4@SP onto the carbon-based anode. Thus, this study provides new insights into the development of MFCs for refractory and hydrophobic volatile organic compounds removal.

Alkaline earth metals for osteogenic scaffolds: From mechanisms to applications

Regeneration of bone defects is a significant challenge today. As alternative approaches to the autologous bone, scaffold materials have remarkable features in treating bone defects; however, the various properties of current scaffold materials still fall short of expectations. Due to the osteogenic capability of alkaline earth metals, their application in scaffold materials has become an effective approach to improving their properties. Furthermore, numerous studies have shown that combining alkaline earth metals leads to better osteogenic properties than applying them alone. In this review, the physicochemical and physiological characteristics of alkaline earth metals are introduced, mainly focusing on their mechanisms and applications in osteogenesis, especially magnesium (Mg), calcium (Ca), strontium (Sr), and barium (Ba). Furthermore, this review highlights the possible cross-talk between pathways when alkaline earth metals are combined. Finally, some of the current drawbacks of scaffold materials are enumerated, such as the high corrosion rate of Mg scaffolds and defects in the mechanical properties of Ca scaffolds. Moreover, a brief perspective is also provided regarding future directions in this field. It is worth exploring that whether the levels of alkaline earth metals in newly regenerated bone differs from those in normal bone. The ideal ratio of each element in the bone tissue engineering scaffolds or the optimal concentration of each elemental ion in the created osteogenic environment still needs further exploration. The review not only summarizes the research developments in osteogenesis but also offers a direction for developing new scaffold materials.

A Review of Biomimetic and Biodegradable Magnetic Scaffolds for Bone Tissue Engineering and Oncology

Bone defects characterized by limited regenerative properties are considered a priority in surgical practice, as they are associated with reduced quality of life and high costs. In bone tissue engineering, different types of scaffolds are used. These implants represent structures with well-established properties that play an important role as delivery vectors or cellular systems for cells, growth factors, bioactive molecules, chemical compounds, and drugs. The scaffold must provide a microenvironment with increased regenerative potential at the damage site. Magnetic nanoparticles are linked to an intrinsic magnetic field, and when they are incorporated into biomimetic scaffold structures, they can sustain osteoconduction, osteoinduction, and angiogenesis. Some studies have shown that combining ferromagnetic or superparamagnetic nanoparticles and external stimuli such as an electromagnetic field or laser light can enhance osteogenesis and angiogenesis and even lead to cancer cell death. These therapies are based on in vitro and in vivo studies and could be included in clinical trials for large bone defect regeneration and cancer treatments in the near future. We highlight the scaffolds' main attributes and focus on natural and synthetic polymeric biomaterials combined with magnetic nanoparticles and their production methods. Then, we underline the structural and morphological aspects of the magnetic scaffolds and their mechanical, thermal, and magnetic properties. Great attention is devoted to the magnetic field effects on bone cells, biocompatibility, and osteogenic impact of the polymeric scaffolds reinforced with magnetic nanoparticles. We explain the biological processes activated due to magnetic particles' presence and underline their possible toxic effects. We present some studies regarding animal tests and potential clinical applications of magnetic polymeric scaffolds.

Advanced 3D Magnetic Scaffolds for Tumor-Related Bone Defects

The need for bone substitutes is a major challenge as the incidence of serious bone disorders is massively increasing, mainly attributed to modern world problems, such as obesity, aging of the global population, and cancer incidence. Bone cancer represents one of the most significant causes of bone defects, with reserved prognosis regarding the effectiveness of treatments and survival rate. Modern therapies, such as hyperthermia, immunotherapy, targeted therapy, and magnetic therapy, seem to bring hope for cancer treatment in general, and bone cancer in particular. Mimicking the composition of bone to create advanced scaffolds, such as bone substitutes, proved to be insufficient for successful bone regeneration, and a special attention should be given to control the changes in the bone tissue micro-environment. The magnetic manipulation by an external field can be a promising technique to control this micro-environment, and to sustain the proliferation and differentiation of osteoblasts, promoting the expression of some growth factors, and, finally, accelerating new bone formation. By incorporating stimuli responsive nanocarriers in the scaffold's architecture, such as magnetic nanoparticles functionalized with bioactive molecules, their behavior can be rigorously controlled under external magnetic driving, and stimulates the bone tissue formation.

Nanozyme-Based Lateral Flow Immunoassay (LFIA) for Extracellular Vesicle Detection

Extracellular vesicles (EVs) are biological nanoparticles of great interest as novel sources of biomarkers and as drug delivery systems for personalized therapies. The research in the field and clinical applications require rapid quantification. In this study, we have developed a novel lateral flow immunoassay (LFIA) system based on Fe₃O₄ nanozymes for extracellular vesicle (EV) detection. Iron oxide superparamagnetic nanoparticles (Fe₃O₄ MNPs) have been reported as peroxidase-like mimetic systems and competent colorimetric labels. The peroxidase-like capabilities of MNPs coated with fatty acids of different chain lengths (oleic acid, myristic acid, and lauric acid) were evaluated in solution with H₂O₂ and 3,3,5,5-tetramethylbenzidine (TMB) as well as on strips by biotin–neutravidin affinity assay. As a result, MNPs coated with oleic acid were applied as colorimetric labels and applied to detect plasma-derived EVs in LFIAs via their nanozyme effects. The visual signals of test lines were significantly enhanced, and the limit of detection (LOD) was reduced from 5.73 × 10⁷ EVs/μL to 2.49 × 10⁷ EVs/μL. Our work demonstrated the potential of these MNPs as reporter labels and as nanozyme probes for the development of a simple tool to detect EVs, which have proven to be useful biomarkers in a wide variety of diseases.

Inorganic Nanoparticles in Bone Healing Applications

Modern biomedicine aims to develop integrated solutions that use medical, biotechnological, materials science, and engineering concepts to create functional alternatives for the specific, selective, and accurate management of medical conditions. In the particular case of tissue engineering, designing a model that simulates all tissue qualities and fulfills all tissue requirements is a continuous challenge in the field of bone regeneration. The therapeutic protocols used for bone healing applications are limited by the hierarchical nature and extensive vascularization of osseous tissue, especially in large bone lesions. In this regard, nanotechnology paves the way for a new era in bone treatment, repair and regeneration, by enabling the fabrication of complex nanostructures that are similar to those found in the natural bone and which exhibit multifunctional bioactivity. This review aims to lay out the tremendous outcomes of using inorganic nanoparticles in bone healing applications, including bone repair and regeneration, and modern therapeutic strategies for bone-related pathologies.

Engineered Magnetic Nanocomposites to Modulate Cellular Function

Magnetic nanoparticles (MNPs) have various applications in biomedicine, including imaging, drug delivery and release, genetic modification, cell guidance, and patterning. By combining MNPs with polymers, magnetic nanocomposites (MNCs) with diverse morphologies (core-shell particles, matrix-dispersed particles, microspheres, etc.) can be generated. These MNCs retain the ability of MNPs to be controlled remotely using external magnetic fields. While the effects of these biomaterials on the cell biology are still poorly understood, such information can help the biophysical modulation of various cellular functions, including proliferation, adhesion, and differentiation. After recalling the basic properties of MNPs and polymers, and describing their coassembly into nanocomposites, this review focuses on how polymeric MNCs can be used in several ways to affect cell behavior. A special emphasis is given to 3D cell culture models and transplantable grafts, which are used for regenerative medicine, underlining the impact of MNCs in regulating stem cell differentiation and engineering living tissues. Recent advances in the use of MNCs for tissue regeneration are critically discussed, particularly with regard to their prospective involvement in human therapy and in the construction of advanced functional materials such as magnetically operated biomedical robots.

The fabrication of halloysite nanotube-based multicomponent hydrogel scaffolds for bone healing

Bone tissue engineering, as an alternative for common available therapeutic approaches, has been developed to focus on reconstructing of the missing tissues and restoring their functionality. In this work, three-dimensional (3D) nanocomposite scaffolds of polycaprolactone-polyethylene glycol-polycaprolactone/gelatin (PCEC/Gel) were prepared by freeze-drying method. Biocompatible nanohydroxyapatite (nHA), iron oxide nanoparticle (Fe₃O₄) and halloysite nanotube (HNT) powders were added to the polymer matrix aiming to combine the osteogenic activity of nHA or Fe₃O₄ with high mechanical strength of HNT. The scanning electron microscope (SEM) methods was utilized to characterize the nanotube morphology of HNT as well as nanoparticles of Fe₃O₄ and nHA. Prepared scaffolds were characterized via Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction analysis (XRD), and SEM methods. In addition, the physical behavior of scaffolds was evaluated to explore the influence of HNT on the physicochemical properties of composites. Cell viability and attachment were investigated by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide) assay and SEM on human dental pulp-derived mesenchymal stem cells (h-DPSCs) in-vitro. Cell proliferation was observed without any cytotoxicity effect on h-DPSCs for all examined scaffolds. Alizarin red (ARS) and alkaline phosphatase (ALP) staining were carried out to determine the osteoconductivity of scaffolds. The data demonstrated that all PCEC/Gel/HNT hydrogel scaffolds supported osteoblast differentiation of hDPSCs with moderate effects on cell proliferation. Moreover, PCEC/Gel/HNT/nHA with proper mechanical strength showed better biological activity compared to PCEC/Gel/HNT/Fe₃O₄ and PCEC/Gel/HNT scaffolds. Therefore, this study suggested that with proper fillers content, PCEC/Gel/HNT nanocomposite hydrogels alone or in a complex with nHA, Fe₃O₄ could be a suitable candidate for hard tissue regeneration.

Biofunctional phosphorylated magnetic scaffold for bone tissue engineering

The development of highly bioactive engineered scaffolds is required to promote bone regeneration and the success of bone tissue engineering treatment approaches. This study attempts to fabricate a biofunctional magnetic scaffold based on new phosphorylated polycaprolactone combined with gelatin (MNPs-PCL-P/gelatin). Phosphorylated polymer and magnetic nanoparticles (MNPs) were synthesized and characterized by NMR, FT-IR, TEM, and DLS instruments. The synthetic polymer, MNPs, and biopolymer were mixed then freeze-dried to prepare a porous scaffold. Physiochemical assessments showed that a scaffold with well-developed porous morphology, and stable structure was obtained. MNPs-PCL-P/gelatin scaffold had no toxicity on human dental pulp stem cells (hDPSCs). The use of phosphorous-containing polymer resulted in improvement of the scaffold's osteoconductivity to support proper cell attachment and promote cell proliferation. Phosphate group by mimicking function of bone phosphate groups stimulate bone mineralization that reflected by alizarin red S staining assay. The presence of MNPs resulted in higher ALP activity and increased expression level of RUNX2, BMP2 osteogenic biomarkers. Also, phosphorylation enhanced osteoinductivity of scaffold and upregulate RUNX2, BMP2, COL1A1, and OCN genes in phosphors-containing scaffold test groups. It seems that biocompatible MNPs-PCL-P/gelatin scaffold possesses the potential of applications in bone tissue engineering.

Progress and prospects of magnetic iron oxide nanoparticles in biomedical applications: A review

Nanoscience has been considered as one of the most substantial research in modern science. The utilization of nanoparticle (NP) materials provides numerous advantages in biomedical applications due to their unique properties. Among various types of nanoparticles, the magnetic nanoparticles (MNPs) of iron oxide possess intrinsic features, which have been efficiently exploited for biomedical purposes including drug delivery, magnetic resonance imaging, Magnetic-activated cell sorting, nanobiosensors, hyperthermia, and tissue engineering and regenerative medicine. The size and shape of nanostructures are the main factors affecting the physicochemical features of superparamagnetic iron oxide nanoparticles, which play an important role in the improvement of MNP properties, and can be controlled by appropriate synthesis strategies. On the other hand, the proper modification and functionalization of the surface of iron oxide nanoparticles have significant effects on the improvement of physicochemical and mechanical features, biocompatibility, stability, and surface activity of MNPs. This review focuses on popular methods of fabrication, beneficial surface coatings with regard to the main required features for their biomedical use, as well as new applications.