Search Results (1,812)

Poly(glycerol sebacate) (PGS) is a biodegradable elastomer with high potential for tissue engineering. However, its limited structural stability and degradation control restrict broader biomedical applications. This study presents an integrated fabrication strategy for highly porous PGS-IPDI scaffolds reinforced with two types of hydroxyapatite of distinct origin (HAP_B and HAP_ICMB). By combining low-temperature urethane crosslinking with thermally induced phase separation and salt leaching, we obtained scaffolds with interconnected micro–macroporous architectures and exceptionally high porosity (up to 98%). The comparative incorporation of phase-pure nanometric HAP_B and biphasic HAP_ICMB enabled the identification of composition-dependent differences in water uptake, structural stability, and mineralization tendencies. Furthermore, degradation behavior was systematically evaluated in four physiologically relevant media (PBS, SBF, artificial saliva, Ringer’s solution), revealing distinct degradation pathways associated with each environment. The results provide new insight into how hydroxyapatite type and incubation medium collectively govern the long-term performance of chemically crosslinked PGS-based scaffolds. Full article

Pulsed electric fields (PEFs) are widely recognized as a non-thermal, selective physical therapy with wide clinical application in tumor ablation. The pulse width determines how electrical energy is distributed across plasma membrane to intracellular organelles. However, under an engineering-defined equal-dose condition (N·E²·tp), which serves as a practical control parameter rather than a measure of true cellular energy absorption, systematic and comparable experimental characterization of cellular and subcellular responses across pulse widths from the microsecond to nanosecond range remains limited. In this study, PEFs with pulse widths ranging from 100 μs to 50 ns were applied under equal-dose constraints, and cellular responses were evaluated using transmission electron microscopy (TEM), multi-organelle fluorescence imaging, and flow cytometry. The results indicate that pulse-width-dependent effects were observed under a fixed pulse-number, dose-equalized framework in which electric field strength varied across conditions. Structural and functional changes were observed in multiple organelles, including the nucleus, mitochondria, endoplasmic reticulum, and Golgi apparatus. Notably, nanosecond pulses were more effective in inducing mitochondrial membrane potential loss and increasing the proportion of apoptotic or non-viable cells. These findings demonstrate that, under equal-dose conditions, pulse width is a key temporal parameter governing PEF-induced biological effects, indicating that identical dose constraints do not necessarily result in equivalent biological responses. This work provides experimental foundation for parameter selection and optimization in PEF-based biomedical applications. Full article

This review provides a comprehensive overview of recent progress in chitin-based nanomaterials and their composite engineering. Particular focus is placed on techniques for constructing self-assembled chitin nanofibers (ChNFs) with tightly bundled fibrillar structures, as well as strategies for fabricating composites in which the ChNFs serve as reinforcing components, combined with natural polymeric matrices. In addition, high-crystalline scaled-down (SD-)ChNFs were fabricated through partial deacetylation of the ChNFs, followed by electrostatic repulsive disassembly of the abovementioned bundled fibrils in aqueous acetic acid, which were further used to reinforce composites comprising the other polysaccharides. Mixing the SD-ChNFs with low-crystalline chitin substrates further enabled the fabrication of all-chitin composites (AChCs) that exploit crystallinity contrast to achieve enhanced tensile strength. Moreover, the AChC films exhibited high cell-adhesive properties and promoted the formation of three-dimensional cell-networks, highlighting their potential for biomedical applications. Full article

Flow sensing is essential in biomedical engineering, industrial process control, and environmental monitoring. Conventional sensors, while accurate, are often constrained by high fabrication costs, complex processes, and limited design flexibility, restricting their use in disposable or rapidly customizable applications. This paper presents a novel ultra-low-cost airflow sensor fabricated entirely through fused deposition modeling 3D printing. The device employs a cantilever-based structure printed with PETg filament, followed by the deposition of a conductive ABS piezoresistive layer in a two-step process requiring no curing or post-processing. Experimental characterization reveals that the sensor operates in an ultra-low pressure range of 0.88–26.68 Pa, corresponding to flow velocities of 1.2–6.6 m/s. The sensor achieves a sensitivity of 967 Ω/Pa, a resolution of 9.27 Pa, and a detection limit of 83.27 Pa, with a total resistance change of approximately 51.5 kΩ. This kilo-ohm-scale response enables direct readout via a digital multimeter without requiring Wheatstone bridges or instrumentation amplifiers. The minimalist design, combined with sub-5 min fabrication time and material cost below $0.05, positions this sensor as an accessible platform for disposable, scalable, and resource-constrained flow monitoring applications in both biomedical and industrial contexts. Full article

Cryotherapy and radiofrequency (RF) treatments modulate tissue temperature to induce therapeutic effects; however, improper application can result in thermal injury. Traditional temperature-based monitoring methods rely on multiple thermal sensors whose accuracy strongly depends on their number and spatial positioning, often failing to detect early tissue crystallization. This study introduces a fractional order bioimpedance modelling framework for the early detection of tissue freezing during cryogenic and thermal medical treatments, with the feasibility and effectiveness of this approach having been reported in our prior publications. While bioimpedance spectroscopy itself is a well-est. The corresponablished technique in biomedical engineering, its novel application to predict and identify premature freezing events provides a new pathway for safe and efficient energy-based therapies. Fractional-order models derived from the Cole family accurately reproduce the complex electrical behavior of biological tissues using fewer parameters than classical integer-order models, thus reducing both hardware requirements and computational cost. Experimental impedance data from human abdominal, gluteal, and femoral regions were modelled to extract fractional parameters that serve as sensitive indicators of phase-transition onset. The results demonstrate that the proposed approach enables real-time identification of freezing-induced electrical transitions, offering a physiologically grounded alternative to conventional temperature-based monitoring. Furthermore, the fractional order bioimpedance method exhibits high reproducibility and selectivity, and its analytical figures of merit, including the limits of detection and quantification, support its use for reliable real-time tissue monitoring and early injury detection. Overall, the proposed fractional order bioimpedance framework enhances both safety and control precision in cryogenic and thermal medical applications. Full article

Ionic liquids (ILs) have emerged as multifunctional compounds with low volatility, high thermal stability, and tunable solvation capabilities, making them highly promising for biomedical applications. First explored in the late 1990s and early 2000s for enhancing the thermal stability of enzymes, antimicrobial agents, and controlled release systems, ILs have since gained significant attention in drug delivery, antimicrobial treatments, medical imaging, and biosensing. This review examines the diverse functions of ILs in contemporary therapeutics and diagnostics, highlighting their transformative capabilities in improving drug solubility, bioavailability, transdermal permeability, and pathogen inactivation. In drug delivery, ILs improve solubility of bioactive compounds, with several IL formulations achieving substantial solubility enhancements for poorly soluble drugs. Bio-ILs, in particular, show promise in enhancing drug delivery systems, such as improving transdermal permeability. ILs also exhibit significant antimicrobial and antiviral activity, offering new avenues for combating resistant pathogens. Despite their broad potential, challenges such as cytotoxicity, long-term metabolic effects, and the stability of ILs in physiological conditions persist. While much research has focused on their physicochemical properties, biological activity and in vivo studies are still underexplored. The future directions for ILs in biomedical applications include the development of bioengineered ILs and hybrid ILs, combining functional components like nanoparticles and polymers to create multifunctional materials. These ILs, derived from renewable resources, show great promise in personalized medicine and clinical applications. Further research is necessary to evaluate their pharmacokinetics, biodistribution, and long-term safety to fully realize their biomedical potential. This study emphasizes the potential of ILs to transform therapeutic and diagnostic technologies by highlighting present shortcomings and offering pathways for clinical translation, while also debating the need for continuous research to fully utilize their biomedical capabilities. Full article

Microbial biosurfactants (mBSs) are bioactive molecules with diverse applications, notably as antimicrobial agents against antibiotic-resistant pathogens. Produced by bacteria and yeasts, mBSs are classified as glycolipids, lipopeptides, polymeric, and particulate types. The global rise in multidrug-resistant organisms, such as Escherichia coli, Klebsiella pneumoniae, Salmonella typhimurium, Pseudomonas aeruginosa, and Acinetobacter baumannii, underscores the urgent need for new antimicrobial strategies. mBSs disrupt microbial growth by interacting with the lipid components of pathogens, offering promising alternatives to conventional antibiotics. This review highlights the sources, chemical structures, and properties of mBSs, their antimicrobial activities, synergistic effects with antibiotics, and structure–activity relationships. Special emphasis is placed on surfactant modification, where targeted changes—such as valine substitution in surfactin—significantly lower critical micelle concentrations (CMC) and enhance antimicrobial potency. Such rational engineering demonstrates how biosurfactants can be tailored for improved biomedical performance while minimizing cytotoxicity. In parallel, artificial intelligence (AI) algorithms, including artificial neural networks and genetic algorithms, optimize yields, predict substrate suitability from agricultural residues, and guide microbial strain engineering. AI models can predict interfacial behavior and synchronize fermentation with purification. Advancing the understanding of mBS interactions with microbial membranes, combined with modification strategies and AI-guided optimization, is essential for developing targeted therapies against resistant infections. Future research should integrate these approaches to engineer novel derivatives, reduce costs, and validate clinical potential through comprehensive in vivo studies. Full article

Conductive hydrogels have gained considerable interest in the biomedical field because they provide a soft, hydrated, and electrically active microenvironment that closely resembles native tissue. Their unique combination of electrical conductivity and biocompatibility enables monitoring and modulation of biological activities. With the rapid development of conductive hydrogel technologies in recent years, a comprehensive overview is needed to clarify their biological functions and the latest biomedical applications. This review first summarizes the fundamental design strategies, fabrication methods, and conductive mechanisms of conductive hydrogels. We then highlight their applications in wearable device, implanted bioelectronics, wound healing, neural regeneration and cell regulation, accompanied by discussions of the underlying biological and electroactive mechanisms. Potential challenges and future directions, including strategies to optimize fabrication methods, balance key material properties, and tailor conductive hydrogels for diverse biomedical applications, are also highlighted. Finally, we discuss the existing limitations and future perspectives of the biomedical applications of conductive hydrogels. We hope that this article may provide some useful insights to support their further development and potential biomedical applications. Full article

Microneedle (MN) technologies have emerged as a groundbreaking platform for transdermal and intradermal drug delivery, offering a minimally invasive alternative to oral and parenteral routes. Unlike passive transdermal systems, MNs allow the permeation of hydrophilic macromolecules, such as peptides, proteins, and vaccines, by penetrating the stratum corneum barrier without causing pain or tissue damage, unlike hypodermic needles. Recent advances in materials science, microfabrication, and biomedical engineering have enabled the development of various MN types, including solid, coated, dissolving, hollow, hydrogel-forming, and hybrid designs. Each type has unique mechanisms, fabrication techniques, and pharmacokinetic profiles, providing customized solutions for a range of therapeutic applications. The integration of 3D printing technologies and stimulus-responsive polymers into MN systems has enabled patches that combine drug delivery with real-time physiological sensing. Over the years, MN applications have grown beyond vaccines to include the delivery of insulin, anticancer agents, contraceptives, and various cosmeceutical ingredients, highlighting the versatility of this platform. Despite this progress, broader clinical and commercial adoption is still limited by issues such as scalable and reliable manufacturing, patient acceptance, and meeting regulatory expectations. Overcoming these barriers will require coordinated efforts across engineering, clinical research, and regulatory science. This review thoroughly summarizes MN technologies, beginning with their classification and drug-delivery mechanisms, and then explores innovations, therapeutic uses, and translational challenges. It concludes with a critical analysis of clinical case studies and a future outlook for global healthcare. By comparing technological progress with regulatory and commercial hurdles, this article highlights the opportunities and limitations of MN systems as a next-generation drug-delivery platform. Full article

Carbon nanotube (CNT) and graphene-reinforced nanocomposites have become exceptional multifunctional materials because of their exceptional mechanical, thermal, and electrical properties. Recent developments in synthesis methods, dispersion strategies, and interfacial engineering have effectively overcome agglomeration-related limitations by significantly improving filler distribution, matrix compatibility, and load-transfer efficiency. These nanocomposites have better wear durability, corrosion resistance, and surface properties like super-hydrophobicity. A comparative analysis of polymer, metal, and ceramic matrices finds benefits for applications in biomedical, construction, energy, defense, and aeronautics. Functionally graded architecture, energy-harvesting nanogenerators, and additive manufacturing are some of the new fabrication processes that enhance design flexibility and functional integration. In recent years, scalability, life-cycle evaluation, and environmentally friendly processing have all gained increased attention. The development of next-generation, high-performance graphene and carbon nanotube (CNT)-based nanocomposites is critically reviewed in this work, along with significant obstacles and potential next steps. Full article

Recent advances in deep learning have had a significant impact on biomedical applications, driving precise actions in automated diagnostic processes. However, integrating neural networks into medical devices requires meeting strict requirements regarding computing power, energy efficiency, reconfigurability, and latency, essential conditions for real-time inference. Field-Programmable Gate Array (FPGA) architectures provide a high level of flexibility, performance, and parallel execution, thus making them a suitable option for the real-world implementation of machine learning (ML) and deep learning (DL) models in systems dedicated to the analysis of physiological signals. This paper presents a review of intelligent algorithms for electrocardiogram (ECG) signal classification, including Support Vector Machines (SVMs), Artificial Neural Networks (ANNs), Recurrent Neural Networks (RNNs), Long Short-Term Memory Networks (LSTMs), and Convolutional Neural Networks (CNNs), which have been implemented on FPGA platforms. A comparative evaluation of the performances of these hardware-accelerated solutions is provided, focusing on their classification accuracy. At the same time, the FPGA families used are analyzed, along with the reported performances in terms of operating frequency, power consumption, and latency, as well as the optimization strategies applied in the design of deep learning hardware accelerators. The conclusions emphasize the popularity and efficiency of CNN architectures in the context of ECG signal classification. The study aims to offer a current overview and to support specialists in the field of FPGA design and biomedical engineering in the development of accelerators dedicated to physiological signals analysis. Full article

This paper explores the potential of amorphous and nanocrystalline glass-coated microwires as highly versatile, miniaturized sensing elements, leveraging their intrinsic nonlinear magnetization dynamics. In magnetic systems, this approach is particularly advantageous because the degree of nonlinearity can be externally tuned using stimuli such as applied magnetic fields, mechanical stress, or temperature variations. From this context, we summarize key properties of microwires—including bistability, a specific easy magnetization direction, internal stress distributions, and magnetostriction—that can be tailored through composition and annealing. In this review, we compare for the first time two key contactless readout methodologies: (i) time-domain detection of the switching field and (ii) frequency-domain harmonic analysis of the induced voltage. These principles have been successfully applied to a broad range of practical sensors, including devices for monitoring mechanical stress in structural materials, measuring temperature in biomedical settings, and detecting magnetic particles. Together, these advances highlight the potential of microwires for embedded, wireless sensing in both engineering and medical applications. Full article

Polyhydroxyalkanoates (PHAs), a family of biodegradable polyesters produced through microbial fermentation of carbon-rich residues, are emerging as attractive alternatives to petroleum-based plastics. Their appeal lies in their exceptional biocompatibility, inherent biodegradability, and tunable physicochemical properties across diverse applications. These materials are environmentally friendly not just at the end of their life, but throughout their entire production–use–disposal cycle. This mini-review presents an update on the expanding biomedical relevance of PHAs, with emphasis on their utility in tissue engineering and drug delivery platforms. In addition, current clinical evaluations and regulatory frameworks are briefly discussed, underscoring the translational potential of PHAs in meeting unmet medical needs. As the healthcare sector advances toward environmentally responsible and patient-focused innovations, PHAs exemplify the convergence of waste valorization and biomedical progress, transforming discarded resources into functional materials for repair, regeneration, and healing. Full article

Protein-based hydrogels are increasingly recognized as promising biomaterials for advanced drug delivery, owing to their biocompatibility, biodegradability, and ability to recreate extracellular matrix-like environments. By tailoring the protein source, crosslinking strategy, molecular architecture, and functionalization, these hydrogels can be engineered to mimic the mechanical and biological features of native tissues. Protein-derived hydrogels are currently explored across biomedical and pharmaceutical fields, including drug delivery systems, wound healing, tissue engineering, and, notably, cancer therapy. In recent years, growing attention has been directed toward natural protein hydrogels because of their inherent bioactivity and versatile physicochemical properties. This review provides an updated overview of protein-based hydrogel classification, properties, and fabrication methods. It highlights several widely studied natural proteins, such as gelatin, collagen, silk fibroin, soy protein, casein, and whey protein, that can form hydrogels through physical, chemical, or enzymatic crosslinking. These materials offer tunable mechanical behavior, controllable degradation rates, and abundant functional groups that support efficient drug loading and the development of stimuli-responsive platforms. Furthermore, we examine current advances in their application as drug delivery systems, with particular emphasis on cancer treatment. Protein-based hydrogels have demonstrated the ability to protect therapeutic molecules, provide sustained or targeted release, and enhance therapeutic effectiveness. Although critical challenges, such as batch-to-batch variability, sterilization-induced denaturation, and the requirement for comprehensive long-term immunogenicity assessment, must still be addressed to enable successful translation from preclinical studies to clinical application, ongoing advances in the design and functionalization of natural protein hydrogels highlight their promise as next-generation platforms for precision drug delivery. Full article

Controlling cell attachment to substrates with spatiotemporal precision is a key technological foundation in fields such as tissue engineering, cell sorting, and cell–cell interaction analysis. Among existing approaches, azobenzene-based photocontrollable systems offer a promising strategy for the reversible regulation of cell adhesion. However, most conventional systems rely on the intrinsic adhesion capacity of adherent cells. Consequently, although the importance of non-adherent cell types has grown in biomedical research, their dynamic manipulation remains insufficiently explored. In this study, we developed a versatile system to control cell adhesion based on host–guest interactions between an azobenzene–lipid conjugate and a cyclodextrin-functionalized substrate. Using human chronic myelogenous leukemia (K562) cells, we successfully demonstrated photocontrolled adhesion and detachment, confirming the applicability of this system to non-adherent cells. Furthermore, we quantitatively measured the adhesion force and observed an inverse correlation between adhesion efficiency and adhesion force for different PEG linker lengths (2k, 4k, and 8k). This finding demonstrates the critical role of the linker length in effective cell surface modification. In conclusion, the proposed system establishes a photocontrollable adhesion method applicable to non-adherent cells, demonstrating its potential as a versatile technology for broad applications. Full article