Collagen-based materials, renowned for their biocompatibility and minimal immunogenicity, serve as exemplary substrates in a myriad of biomedical applications. Collagen-based micro/nanogels, in particular, are valued for their increased surface area, tunable degradation rates, and ability to facilitate targeted drug delivery, making them instrumental in advanced therapeutics and tissue engineering endeavors. Although extensive reviews on micro/nanogels exist, they tend to cover a wide range of biomaterials and lack a specific focus on collagen-based materials. The current review offers an in-depth look into the manufacturing technologies, drug release mechanisms, and biomedical applications of collagen-based micro/nanogels to address this gap. First, we provide an overview of the synthetic strategies that allow the precise control of the size, shape, and mechanical strength of these collagen-based micro/nanogels by controlling the degree of cross-linking of the materials. These properties are crucial for their performance in biomedical applications. We then highlight the environmental responsiveness of these collagen-based micro/nanogels, particularly their sensitivity to enzymes and pH, which enables controlled drug release under various pathological conditions. The discussion then expands to include their applications in cancer therapy, antimicrobial treatments, bone tissue repair, and imaging diagnosis, emphasizing their versatility and potential in these critical areas. The challenges and future perspectives of collagen-based micro/nanogels in the field are discussed at the end of the review, with an emphasis on the translation to clinical practice. This comprehensive review serves as a valuable resource for researchers, clinicians, and scientists alike, providing insights into the current state and future directions of collagen-based micro/nanogel research and development.
Collagen/chemistry* ; Drug Delivery Systems/methods* ; Humans ; Tissue Engineering/methods* ; Animals ; Biocompatible Materials/chemistry*

The evaluation of blood compatibility of biomaterials is crucial for ensuring the clinical safety of implantable medical devices. To address the limitations of traditional testing methods in real-time monitoring and electrical property analysis, this study developed a portable electrical impedance tomography (EIT) system. The system uses a 16-electrode design, operates within a frequency range of 1 to 500 kHz, achieves a signal to noise ratio (SNR) of 69.54 dB at 50 kHz, and has a data collection speed of 20 frames per second. Experimental results show that the EIT system developed in this study is highly consistent with a microplate reader ( R ²=0.97) in detecting the hemolytic behavior of industrial-grade titanium (TA3) and titanium alloy-titanium 6 aluminum 4 vanadium (TC4) in anticoagulated bovine blood. Additionally, with the support of a multimodal image fusion Gauss-Newton one-step iterative algorithm, the system can accurately locate and monitor in real-time the dynamic changes in blood permeation and coagulation caused by TC4 in vivo. In conclusion, the EIT system developed in this study provides a new and effective method for evaluating the blood compatibility of biomaterials.
Electric Impedance ; Animals ; Tomography/instrumentation* ; Biocompatible Materials ; Materials Testing/instrumentation* ; Cattle ; Titanium ; Alloys ; Prostheses and Implants

This review article summarizes the current modification methods employed to enhance the osseointegration properties of polyetheretherketone (PEEK), a novel biomaterial. Our analysis highlights that strategies such as surface treatment, surface modification, and the incorporation of bioactive composites can markedly improve the bioactivity of PEEK surfaces, thus facilitating their effective integration with bone tissue. However, to ensure widespread application of PEEK in the medical field, particularly in oral implantology, additional experiments and long-term clinical evaluations are required. Looking ahead, future research should concentrate on developing innovative modification techniques and assessment methodologies to further optimize the performance of PEEK implant materials. The ultimate goal is to provide the clinical setting with even more reliable solutions.
Benzophenones ; Ketones/chemistry* ; Polyethylene Glycols/chemistry* ; Osseointegration ; Humans ; Polymers ; Biocompatible Materials/chemistry* ; Surface Properties ; Prostheses and Implants ; Dental Implants

Adoptive cell transfer (ACT) shows significant efficacy against hema-tological malignancies but is limited in solid tumors due to poor homing, immunosuppre-ssion, and potential toxicity. Biomaterials spanning from nano- to macroscales-including nanoparticles, microspheres/micropatches, and hydrogels-offer unique advantages for ex vivo cell engineering, in vivo delivery, and modulation of the tumor microenvironment. Specifically, nanoparticles enable gene delivery, artificial antigen-presenting cell engi-neering, and immune microenvironment remodeling. Microspheres/micropatches improve immune cell expansion, targeted activation, and localized retention. Hydrogels enhance ACT via in situ genetic engineering, 3D culture support, and cytokine co-delivery. This review summarizes advances in biomaterial-enhanced ACT, highlighting their potential to improve delivery efficiency, amplify antitumor responses, and reduce toxicity. These insights may accelerate the clinical translation of ACT for solid tumors.
Humans ; Neoplasms/therapy* ; Biocompatible Materials/chemistry* ; Immunotherapy, Adoptive/methods* ; Nanoparticles ; Hydrogels ; Adoptive Transfer/methods* ; Animals

Myocardial infarction is a cardiovascular disease with high morbidity and mortality rates. Hydrogel biomaterials mimicking the extracellular matrix have recently been shown to demonstrate excellent biocompatibility, low immunogenicity, favorable biodegradability, and multifunctionality, showcasing significant potential for treatment of myocardial infarction. Hydrogels can provide mechanical support to the damaged myo-cardium, alleviating pathological remodeling. Moreover, their porous structure makes them ideal carriers for localized and sustained drug delivery. Hydrogels derived from various matrices-including polysaccharides, polypeptides, proteins, decellularized extracellular matrix, and synthetic polymers-exhibit distinct properties in terms of biocompatibility, mechanical performance, and drug delivery capacity. These hydrogels support tissue regeneration and enable targeted release of diverse therapeutics, meeting the various therapeutic demands for myocardial repair. In the infarcted myocardial microenvironment, endogenous signals such as low pH, specific enzyme expression, and elevated levels of reactive oxygen species can trigger responsive drug release from hydrogels, while external physical stimuli-such as ultrasound, light, and magnetic fields-can also be employed to precisely control the release process, thereby enhancing therapeutic efficacy and reducing systemic side effects. This review summarizes recent advances in hydrogel-based drug delivery systems for treatment of myocardial infarction, focusing particularly on the characteristics and advantages of different hydrogel materials for myocardial repair. Furthermore, the responsive drug release behavior of hydrogels is analyzed in the context of the cardiac injury microenvironment, providing a reference for future research.
Hydrogels/chemistry* ; Myocardial Infarction/drug therapy* ; Humans ; Drug Delivery Systems/methods* ; Biocompatible Materials ; Drug Carriers

OBJECTIVE: To investigate the biocompatibility of porous WE43 magnesium alloy scaffolds manufactured by 3D printing technology and to observe its effect in treating femoral defects in New Zealand white rabbits. METHODS: In vitro cytotoxicity test was performed using bone marrow mesenchymal stem cells from Sprague Dawley (S-D) rats. According to the different culture media, the cells were divided into 100% extract group, 50% extract group, 10% extract group and control group. After culturing for 1, 3 and 7 days, the cell activity of each group was determined by cell counting kit-8 (CCK-8). In the in vivo experiment, 3.0-3.5 kg New Zealand white rabbits were randomly divided into three groups: Experimental group, bone cement group and blank group, with 9 rabbits in each group. Each rabbit underwent surgery on the left lateral femoral condyle, and a bone defect with a diameter of 5 mm and a depth of 6 mm was created using a bone drill. The experimental group was implanted with WE43 magnesium alloy scaffolds, the bone cement group was implanted with calcium sulfate bone cement, and the blank group was not implanted. Then 4, 8 and 12 weeks after surgery, 3 rabbits in each group were euthanized by carbon dioxide anesthesia, and the femur and important internal organs were sampled. Micro-computed tomography (Micro-CT) scanning was performed on the left lateral femoral condyle. Sections of important internal organs were prepared and stained with hematoxylin-eosin (HE). Hard tissue sections were made from the left lateral femoral condyle and stained with methylene blue acid fuchsin and observed under a microscope. RESULTS: In the cytotoxicity test, the cell survival rate in the 100% extract group was higher than that in the control group (140.56% vs. 100.00%, P < 0.05) on 1 day of culture; there was no statistically significant difference (P>0.05) in cell survival rate among the groups on 3 days of culture; the cell survival rate in the 100% extract group was lower than that in the control group (68.64% vs. 100.00%, P < 0.05) on 7 days of culture. Micro-CT scanning in the in vivo experiment found that most of the scaffolds in the experimental group had been degraded in 4 weeks, with very few high-density scaffolds remaining. In 12 weeks, there was no obvious stent outline. In 4 weeks, a certain amount of gas was generated around the WE43 magnesium alloy scaffold, and the gas was significantly reduced from 8 to 12 weeks. Hard tissue sections showed that a certain amount of extracellular matrix and osteoid were generated around the scaffolds in the experimental group in 4 weeks. In the bone cement group, most of the calcium sulfate bone cement had been degraded. In 8 weeks, the osteoid around the scaffold and its degradation products in the experimental group increased significantly. In 12 weeks, new bone was in contact with the scaffold around the scaffold in the experimental group. There was less new bone in the bone cement group and the blank group. CONCLUSION The porous WE43 magnesium alloy scaffold fabricated by 3D printing process has good biocompatibility and good osteogenic properties, and has the potential to become a new material for repairing bone defects.
Animals ; Rabbits ; Printing, Three-Dimensional ; Alloys/chemistry* ; Tissue Scaffolds/chemistry* ; Magnesium/chemistry* ; Rats, Sprague-Dawley ; Biocompatible Materials ; Mesenchymal Stem Cells/cytology* ; Femur/surgery* ; Rats ; Absorbable Implants ; Male ; Bone Regeneration ; Tissue Engineering/methods* ; Cells, Cultured

As representatives of the third generation of biomedical materials, hydrogels exhibit revolutionary potential in tissue engineering, precision drug delivery, and smart medical devices due to their ability to construct bionic microenvironments. However, the clinical translation of hydrogels is still limited by multidimensional challenges, including biocompatibility, scalable production, and regulatory complexity. This paper systematically reviews the design innovations, functionalization strategies, and translational bottlenecks of hydrogel materials, integrates the latest technological trends, such as 4D printing and AI-driven design, and proposes a collaborative optimization pathway encompassing materials, technology, clinical applications, and policy. By introducing local Chinese innovation cases and monitoring scientific advancements, this study offers solutions that possess both academic significance and practical guidance for the clinical translation of hydrogels.
Hydrogels ; Tissue Engineering ; Translational Research, Biomedical ; Biocompatible Materials ; Humans ; Drug Delivery Systems

Collagen membrane has attracted much attention from researchers due to its excellent properties such as wide source, degradable absorption, and low immunogenicity. However, they are limited by poor mechanical stability and rapid degradation. To enhance their physicochemical properties and biological functions, researchers have developed various strategies, including cross-linking, incorporation of growth factors or drugs, combination with other biomaterials, optimization of composition and structure, and substitution with marine-derived collagen. These advances aim to expand the clinical applications of collagen membranes in oral medicine. With the urgent demand for high-performance biomaterials in oral medicine, summarizing recent progress on collagen membranes provides valuable insights into their mechanisms, clinical efficacy, and limitations, offering reference for optimized design and broader clinical use. Furthermore, further trends may include integrating advanced manufacturing technologies to develop personalized collagen membranes, which could significantly improve therapeutic outcomes in oral diseases.
Collagen/therapeutic use* ; Humans ; Biocompatible Materials/chemistry* ; Membranes, Artificial ; Oral Medicine/methods* ; Tissue Engineering/methods*

Large bone defects in load-bearing bone can result from tumor resection, osteomyelitis, trauma, and other factors. Although bone has the intrinsic potential to self-repair and regenerate, the repair of large bone defects which exceed a certain critical size remains a substantial clinical challenge. Traditionally, repair methods involve using autologous or allogeneic bone tissue to replace the lost bone tissue at defect sites, and autogenous bone grafting remains the "gold standard" treatment. However, the application of traditional bone grafts is limited by drawbacks such as the quantity of extractable bone, donor-site morbidities, and the risk of rejection. In recent years, the clinical demand for alternatives to traditional bone grafts has promoted the development of novel bone-grafting substitutes. In addition to osteoconductivity and osteoinductivity, optimal mechanical properties have recently been the focus of efforts to improve the treatment success of novel bone-grafting alternatives in load-bearing bone defects, but most biomaterial synthetic scaffolds cannot provide sufficient mechanical strength. A fundamental challenge is to find an appropriate balance between mechanical and tissue-regeneration requirements. In this review, the use of traditional bone grafts in load-bearing bone defects, as well as their advantages and disadvantages, is summarized and reviewed. Furthermore, we highlight recent development strategies for novel bone grafts appropriate for load-bearing bone defects based on substance, structural, and functional bionics to provide ideas and directions for future research.
Humans ; Bone Transplantation/methods* ; Weight-Bearing ; Bone Regeneration ; Bone Substitutes ; Bone and Bones ; Animals ; Tissue Scaffolds

Due to their good properties of elastic modulus, degradability and ability to promote bone repair, magnesium alloys have become a research hotspot in research of orthopedic implants. Nevertheless, most of the biomedical magnesium alloys currently available fail to meet the requirements in orthopedics because of their rapid degradation after implantation. Rare earth-magnesium alloys possess excellent corrosion resistance and are expected to become important materials as clinical orthopedic implants. This review summarizes the recent progress in studies of the physiological functions of rare earth elements, the effects of supplementation of rare earth elements on biomechanical properties and the in vitro and in vivo biocompatibility of magnesium alloys, and their contribution to tendon-bone healing, addressing also the current clinical orthopedic applications of different rare earth-magnesium alloys, challenges, and future strategies for improving these alloys.
Alloys/chemistry* ; Magnesium/chemistry* ; Metals, Rare Earth/chemistry* ; Humans ; Biocompatible Materials ; Prostheses and Implants