Search Results (51)

Flexible microscale neural interfaces are advancing current strategies for recording and modulating electrical activity in the brain and spinal cord. The aim of this review is to colligate recent progress in thin-film micro-electrocorticography (μECoG) systems and establish a framework for their translation toward spinal bioelectronic implants. We first outline substrate and electrode material design, ranging from polymeric and hydrogel-based materials to nanostructured conductive materials that enable high-fidelity recording on mechanically compliant platforms. We then summarize structural design rules for μECoG arrays, including electrode size, pitch, and channel scaling, and relate these to data-driven μECoG applications in brain–computer interfaces and closed-loop neuromodulation. Bidirectional μECoG architectures for simultaneous stimulation and recording are examined, with emphasis on safe charge injection, electrochemical and thermal limits, and state-of-the-art hardware and algorithmic strategies for stimulation-artifact suppression. Building upon these cortical technologies, we briefly describe adaptation to spinal interfaces, where anatomical constraints demand optimized mechanical properties. Finally, we discuss the convergence of flexible bioelectronics, wireless power and telemetry, and embedded AI decoding as a path toward autonomous, clinically translatable μECoG and spinal neuroprosthetic systems. Ultimately, by synthesizing these multidisciplinary advances, this review provides a strategic roadmap for overcoming current translational barriers and realizing the full clinical potential of soft bioelectronics. Full article

Hydrogel films have emerged as versatile platforms in biomedical engineering due to their unique physicochemical properties, biocompatibility, and adaptability to diverse therapeutic needs. This review provides a comprehensive overview of hydrogel film materials, including natural biopolymers, synthetic polymers, and multifunctional composites, highlighting their structural and functional diversity. We examine key fabrication techniques—ranging from solvent casting and photopolymerization to advanced methods like microfluidics and 3D printing—and discuss how these influence film architecture and performance. The biomedical applications of hydrogel films span wound healing, drug delivery, tissue engineering, ophthalmology, and implantable biosensors, with recent innovations enabling stimuli-responsive behavior, multi-drug loading, and integration with wearable electronics. Despite their promise, hydrogel films face persistent challenges in mechanical durability, sterilization, storage stability, regulatory approval, and scalable manufacturing. We conclude by identifying critical research gaps and outlining future directions, including AI-guided design, sustainable material development, and the establishment of standardized, regulatory-aligned, and industrially scalable fabrication strategies to accelerate clinical translation. Full article

Silk fibroin (SF) has evolved from a traditional biopolymer to a leading regenerative medicine material. Its combination of mechanical strength, biocompatibility, tunable degradation, and molecular adaptability makes SF a unique matrix that is both bioactive and intelligent. Advances in hydrogel engineering have transformed SF from a passive scaffold into a smart, living hydrogel. These systems can instruct cell fate, sense microenvironmental signals, and deliver therapeutic signals as needed. By incorporating stem cells, progenitors, or engineered immune and microbial populations, SF hydrogels now serve as synthetic niches for organoid maturation and as adaptive implants for tissue regeneration. These platforms replicate extracellular matrix complexity and evolve with tissue, showing self-healing, shape-memory, and stimuli-responsive properties. Such features are redefining biomaterial–cell interactions. SF hydrogels are used for wound healing, musculoskeletal repair, neural and cardiac patches, and developing scalable organoid models for disease and drug research. Challenges remain in maintaining long-term cell viability, achieving clinical scalability, and meeting regulatory standards. This review explores how advances in SF engineering, synthetic biology, and organoid science are enabling SF-based smart living hydrogels in bridging the gap between research and clinical use. Full article

Scaffolds are widely used in bioengineering, both as 3D native tissue-mimicking models for investigating mechanisms under physiological and pathological conditions and also as implantable agents in regenerative medicine. Histological approaches, mainly formalin-fixed paraffin-embedded (FFPE) and frozen sample sectioning, are commonly applied to evaluate cell distribution and tissue-like properties of scaffolds. However, standard histological processing is not always compatible with the materials that scaffolds are made of. Thus, some adaptations to protocols are required to obtain intact sections. In this review we discuss challenges related to the histological processing of scaffolds and solutions to overcome them. We sequentially cover processing steps of the three main histological techniques for sample preparation—cryomicrotomy, FFPE samples microtomy and vibrating microtomy. Furthermore, we highlight the critical considerations in choosing the most appropriate method based on scaffold composition, mechanical properties and the specific research question. The goal of this review is to provide practical guidance on choosing reliable histological evaluation of complex scaffold-based systems in tissue engineering research. Full article

This study investigates the tribo-corrosion behavior of Ti6Al4V biomedical alloy, when sliding against fused filament fabrication (FFF) 3D-printed polyether ether ketone (PEEK) pins in a phosphate-buffered saline (PBS) solution. This research aims to evaluate wear mechanisms and electrochemical responses under simulated physiological conditions, providing critical insights for enhancing the durability and performance of biomedical implants. Potentiodynamic polarization tests demonstrate that the Ti6Al4V alloy possesses excellent corrosion resistance, which is further enhanced under sliding conditions compared to the test without sliding. When tested against 3D-printed PEEK, the alloy exhibits a mixed wear mechanism characterized by both abrasive and adhesive wear. Open-circuit potential (OCP) measurement of Ti6Al4V demonstrates the alloy’s superior electrochemical stability, indicating high corrosion resistance and a favorable coefficient of friction. These findings highlight the potential of 3D-printed PEEK as a viable alternative for biomedical applications, offering rapid patient-specific prototyping, tunable mechanical properties, and improved surface adaptability compared to conventional materials. Full article

The development of functional biosensors is rapidly advancing in response to the growing demand for personalized and continuous healthcare monitoring. Two-dimensional (2D) nanostructured materials have attracted significant attention for next-generation biosensors due to their exceptional physicochemical properties, including a high surface-to-volume ratio, excellent electrical conductivity, and mechanical flexibility. The integration of 2D materials with biological recognition elements offers synergistic improvements in sensitivity, stability, and overall sensor performance. These unique properties make 2D materials particularly well-suited for constructing wearable and implantable biosensors, which require conformal contact with soft tissues, mechanical adaptability to body movement, and reliable operation under physiological conditions. This review highlights recent advances in functionalized and composite 2D materials for wearable and implantable biosensing applications. We focus on key strategies in surface modification and hybrid nanostructure engineering aimed at optimizing performance in dynamic, body-integrated environments. Finally, we discuss current challenges and future directions for clinical translation, emphasizing the potential of 2D-material-based biosensors to drive progress in personalized and precision medicine. Full article

The success of orthopedic implants critically depends on achieving mechanical and biological compatibility with bone tissue. Traditional titanium implants often suffer from high stiffness, which induces stress shielding, a phenomenon that compromises implant integration and accelerates prosthetic loosening. This study introduces an innovative approach to mitigate these limitations by engineering a porous titanium substrate with a controlled microstructure. Utilizing sodium chloride as a spacer holder, an elution and sintering process was applied at 1250 °C under high vacuum conditions to reduce the material’s elastic modulus. By manipulating NaCl volume fractions (20%, 25%, 30%, and 35%), porous titanium samples were created with elastic moduli between 16.37 and 22.56 GPa, closely matching cortical bone properties (4 to 20 GPa). A hydroxyapatite coating applied via plasma thermal spraying further enhanced osseointegration of the material. Comprehensive characterization through X-ray diffraction, scanning electron microscopy, and compression testing validated the material’s structural integrity. In vitro cytotoxicity assessments using osteoblast cells demonstrated exceptional cell viability exceeding 70%, confirming the material’s biocompatibility. These findings represent a significant advancement in biomaterial design, offering a promising strategy for developing next-generation joint prostheses with superior mechanical and biological adaptation to bone tissue. Full article

In the context of an ageing society, advancements in medicine and biomedical technology are becoming increasingly important. A major goal is to minimise the number of surgical operations. Magnesium alloys are gaining attention due to their degradable properties, good biocompatibility, and osteoconductivity. However, for implants made from this material to be usable, a precise understanding of the degradation rate and a correspondingly adapted design must be available. This work focuses on constructing a suitable experimental chamber for degradation analysis, as well as investigating the impact of sample positioning on degradation using two different geometries of WE43 alloy for potential use as osteosynthesis implants. Optical and mechanical tests were carried out on these geometries. The tests revealed that the sample positioning in the experimental chamber affects degradation, with the central position yielding the most suitable results for future applications. In addition, mechanical tests demonstrated reduced mechanical properties in the degradation layer. This work provides an initial basis for further investigations into the use of the WE43 alloy as an osteosynthesis implant and supports the numerical calculation of degradation. Full article

Hydrogels and microgels are emerging as pivotal platforms in biomedicine, with significant potential in targeted drug delivery, enhanced infection management, and tissue repair and regeneration. These gels, characterized by their high water content, unique structures, and adaptable mechanical properties, interact seamlessly with biological systems, making them invaluable for controlled and targeted drug release. In the realm of infection management, hydrogels and microgels can incorporate antimicrobial agents, offering robust defenses against bacterial infections. This capability is increasingly important in the fight against antibiotic resistance, providing innovative solutions for infection prevention in wound dressings, surgical implants, and medical devices. Additionally, the biocompatibility and customizable mechanical properties of these gels make them ideal scaffolds for tissue engineering, supporting the growth and repair of damaged tissues. Despite their promising applications, challenges such as ensuring long-term stability, enhancing therapeutic agent loading capacities, and scaling production must be addressed for widespread adoption. This review explores the current advancements, opportunities, and limitations of hydrogels and microgels, highlighting research and technological directions poised to revolutionize treatment strategies through personalized and regenerative approaches. Full article

This research paper explores the development of AI-optimized lattice structures for biomechanics scaffold design, aiming to enhance bone implant functionality by utilizing advanced human–AI systems. The primary objective is to create scaffold structures that mimic the mechanical properties of natural bone and improve bioactivity and biocompatibility, adapting to patient-specific needs. We employed polylactic acid (PLA), calcium hydroxyapatite (cHAP), and reduced graphene oxide (rGO) as base materials, leveraging their synergistic properties. The scaffolds were intricately designed using nTopology software (nTop 5.12) and fabricated via 3D printing techniques, optimizing for biomechanical load-bearing and cellular integration. The study’s findings highlight a notable enhancement in the mechanical properties of the scaffolds, with the Gyroid lattice design demonstrating a 20% higher energy-absorption capacity than traditional designs. Thermal and chemical analysis revealed a 15% increase in the thermal stability of the composites, enhancing their resilience under physiological conditions. However, the research identified minor inconsistencies in filament diameter during 3D printing, which could affect scaffold uniformity. These findings underscore the potential of integrating AI-driven design with advanced material composites in revolutionizing orthopedic implant technologies. Full article

The human amniotic membrane (hAM) has been used as an implant to enhance the regenerative process and control inflammation in different diseases, given their structure, biocompatibility, presence of stem cells and multiple growth factors. The objective of this study was to generate a standardized protocol for obtaining, processing, and storing hAMs that guarantee the conservation of their structural and cellular characteristics as well as their mechanical properties, ensuring their ease of handling, sterility, and quality that allows their implementation for therapeutic purposes in the field of regenerative medicine. The hAMs were obtained from mothers with healthy, full-term, controlled pregnancies and by cesarean section. The hAMs were processed under sterile conditions, manually separated from the placenta and, subsequently, they were frozen in a solution of culture medium plus 50% v/v glycerol. The protocol allows obtaining sterile hAMs composed of both epithelium and stroma with adequate preservation of the amniotic cells. The glycerol’s impact on the mechanical properties may enhance the membrane’s adaptability and conformability to diverse wound surfaces, potentially improving the healing process. It is necessary to repeat microbiological, cell viability and mechanical studies at 6 and 12 months to ensure that long-term frozen conditions do not affect the quality of the hAMs. Full article

The convergence of 3D printing and auxetic materials is paving the way for a new era of adaptive structures. Auxetic materials, known for their unique mechanical properties, such as a negative Poisson’s ratio, can be integrated into 3D-printed objects to enable them to morph or deform in a controlled manner, leading to the creation of 4D-printed structures. Since the first introduction of 4D printing, scientific interest has spiked in exploring its potential implementation in a wide range of applications, from deployable structures for space exploration to shape-adaptive biomechanical implants. In this context, the current paper aimed to develop 4D-printed arterial stents utilizing bioinspired architected auxetic materials made from biocompatible and biodegradable polymeric material. Specifically, three different auxetic materials were experimentally examined at different relative densities, under tensile and compression testing, to determine their mechanical behavior. Based on the extracted experimental data, non-linear hyperelastic finite element material models were developed in order to simulate the insertion of the stent into a catheter and its deployment in the aorta. The results demonstrated that among the three examined structures, the ‘square mode 3’ structure revealed the best performance in terms of strength, at the same time offering the necessary compressibility (diameter reduction) to allow insertion into a typical catheter for stent procedures. Full article

Titanium alloys are widely used in the aerospace, automotive, chemical, and biomedical industries due to their excellent corrosion resistance, mechanical properties, and biocompatibility. However, the surface properties of titanium alloys are often insufficient to meet the increasingly complex requirements of certain applications. Therefore, enhancing the surface performance of titanium alloys in physiological environments has become a key focus of research. In this study, a porous oxide layer was generated on the surface of a titanium substrate through micro-arc oxidation (MAO). This layer served as an intermediate layer for a subsequently deposited polyurethane (PU) coating, providing a strong foundation for adhesion. The high porosity of the MAO layer not only facilitated the adhesion of the PU coating but also protected the titanium alloy, further enhancing its corrosion resistance. The surface microstructure after MAO treatment and the morphological changes after application of the PU coating were characterized using scanning electron microscopy. The PU layer uniformly covered the surface of the MAO layer, significantly improving the smoothness and uniformity of the surface. The increase in surface smoothness due to the PU coating on top of the MAO layer was verified through white light interferometry. Additionally, surface hydrophobicity was assessed through water contact angle measurements. The PU layer over the MAO coating significantly enhanced the hydrophobicity of the titanium alloy’s surface, which is crucial for reducing biofouling and improving the effectiveness of biomedical implants. Finally, electrochemical analysis was conducted to study the corrosion resistance of the titanium alloy after MAO and PU treatment. The titanium alloy with an MAO–PU composite coating exhibited the highest corrosion resistance. The findings revealed that the combination of the MAO layer and PU coating provides an excellent multifunctional protective layer for titanium alloys, not only enhancing their durability but also their ability to adapt to physiological and harsh environments. Full article

Polyetheretherketone (PEEK) has emerged as a revolutionary material in modern dentistry because of its unique combination of mechanical strength, biocompatibility, and versatility. This literature review examines the current applications and future potential of PEEK in various dental disciplines. PEEK’s favorable properties, including its low specific weight, high strength-to-weight ratio, and ability to be easily machined, have led to its adoption in prosthetics, implantology, and dental esthetic restorations. This material has shown promise for fabricating crowns, bridges, removable partial denture frameworks, and implant components. PEEK’s radiolucency and bone-like elastic modulus make it particularly suitable for dental implants and abutments. Additionally, its resistance to degradation and compatibility with various surface treatments enhances its long-term performance in the oral environment. While challenges such as bonding to other dental materials and aesthetic limitations exist, ongoing research is addressing these issues through surface modifications and composite formulations. As the dental field continues to evolve, PEEK’s adaptability and biocompatibility position it a key player in the development of next-generation dental materials and techniques, potentially transforming patient care and treatment outcomes in dentistry. Full article

Bone tissue engineering is a technique that simulates the bone tissue microenvironment by utilizing cells, tissue scaffolds, and growth factors. The collagen hydrogel is a three-dimensional network bionic material that has properties and structures comparable to those of the extracellular matrix (ECM), making it an ideal scaffold and drug delivery system for tissue engineering. The clinical applications of this material are restricted due to its low mechanical strength. In this investigation, a collagen-based gel (atelocollagen/glycerol/pullulan [Col/Gly/Pul] gel) that is moldable and injectable with high adhesive qualities was created by employing a straightforward technique that involved the introduction of Gly and Pul. This study aimed to characterize the internal morphology and chemical composition of the Col/Gly/Pul gel, as well as to verify its osteogenic properties through in vivo and in vitro experiments. When compared to a standard pure Col hydrogel, this material is more adaptable to the complexity of the local environment of bone defects and the apposition of irregularly shaped flaws due to its greater mechanical strength, injectability, and moldability. Overall, the Col/Gly/Pul gel is an implant that shows great potential for the treatment of complex bone defects and the enhancement of bone regeneration. Full article