Medical Device Applications Research Articles

Thread-Filler: A Standardized Combination Therapy

Advanced technology and increasing knowledge about aging faces have combined to create the illusion of thread lifting to replace surgical interventions. However, results that came far beyond expectations led to a heavy suspicion of these tools. However, combined treatments with fillers would have better outcomes with a synergetic effect. In this study, 52 patients were treated with a specific thread, whereas soft tissue support was added to supervene the lifting effect of the threads. With a mean age of 48 years, these patients were treated with 3 pairs of mid and lower facial areas, and one for eyebrows. With a median amount of 5 mL fillers were added simultaneously at the same treatment plan. The follow-up period was 32 months. Assessment with a Likert Scale questionnaire revealed most of the patients (n = 42) were delighted, whereas only one patient was unsatisfied. The only unsatisfied patient experienced the most frustrating complication, which was thread removal due to infection. The literature shows unauthorized, unspecialized applications of such medical devices cause failure and loss of reliability. Therefore, the most important point of this technique is the sterile setting. Other issues that are discussed in this paper also aim to direct the reader to achieve the most benefit of these 2 techniques.

Advancing optical transparency in 3D‐printed PLA parts using chemical post‐processing

AbstractFused filament fabrication (FFF) is an increasingly popular three‐dimensional (3D) printing technology known for its ability to produce complex 3D models at a low‐cost using polymer materials. Despite its advantages, the poor surface finish and high layer resolution in FFF‐printed parts have hindered its wider adoption, particularly for applications requiring high transparency. Thus, the current study investigates the transparency evaluation of chemically post‐processed 3D‐printed transparent polylactic acid (PLA) parts, focusing on enhancing optical transparency. Fused Filament Fabrication was employed to produce transparent parts made from PLA filament, which were subsequently treated at various time settings using various solvents, including tetrahydrofuran (THF), chloroform or trichloromethane (TCM), and ethyl acetate (EA). This study examines the impact of chemical post‐processing on the surface roughness, transparency, mechanical properties, and dimensional accuracy of solvent treated parts. It has been found that the THF solvent with 40 s of immersion time resulted in a maximum transmittance of 74.66% and minimum surface roughness of 1.777 μm. Based on this finding a case study was also conducted to apply the findings of the current investigation to a practical application. The findings highlight the potential of chemical‐based post‐processing techniques to improve the optical properties of 3D printed PLA, offering a promising approach for applications in optics, medical devices, and consumer goods requiring transparent components.Highlights Effect of chemical post‐processing on 3D‐printed PLA parts was investigated. Tetrahydrofuran, chloroform, and ethyl acetate were used as solvents. Surface roughness, transparency, hardness, and dimensional accuracy were analyzed. Reported a maximum transmittance of 74.66% and minimum surface roughness of 1.777 μm.

Medical Devices Applying for Outpatient Medicare Supplemental Payments.

Medicare transitional pass-through payments (TPTPs) provide supplemental reimbursement that is intended to facilitate adoption of new devices in the outpatient setting. The US Centers for Medicare & Medicaid Services (CMS) have historically evaluated manufacturer applications for TPTPs based on newness, cost, and evidence of substantial clinical improvement, ie, the traditional pathway. In 2020, CMS introduced an alternative pathway to allow US Food and Drug Administration (FDA)-designated breakthrough devices to qualify for supplemental reimbursement without demonstrating substantial clinical improvement. To characterize CMS TPTP approval rates and the premarket evidence used by FDA to support authorization of new outpatient medical devices considered for CMS TPTP. This was a cross-sectional study of TPTP applications for new outpatient medical devices from 2017 to 2023. Using the Federal Register, CMS Outpatient Prospective Payment System final rules for fiscal years 2017 through 2023 were obtained, from which all manufacturer applications for TPTPs were identified. For each application, the CMS TPTP review pathway (traditional/alternative), CMS final decision (award/deny), and FDA authorization pathway were assessed. Characteristics of devices considered for CMS TPTPs and design, effectiveness end points, and patient demographic characteristics of premarket clinical studies used to support FDA authorization. CMS approved 17 of 43 (40%) applications for TPTPs, including all 8 (100%) alternative pathway applications for breakthrough devices and 9 of 35 applications (26%) using the traditional pathway. Devices approved for TPTPs were more likely to have been assessed in premarket clinical studies than devices denied TPTPs (12/17 [71%] vs 2/26 [8%]). Among the 14 premarket studies of TPTP-approved devices, 8 (57%) used surrogate markers as primary effectiveness end points and 5 (42%) did not meet all primary end points. The median (IQR) percentage of female, Black, and Hispanic patients among the trials that reported demographic data was 26% (17%-36%), 6% (2%-17%), and 4% (3%-5%), respectively. The findings of this cross-sectional analysis indicated that CMS more commonly awarded supplemental outpatient payment through TPTPs for devices assessed in premarket clinical studies to support FDA authorization. However, these studies often lacked generalizability to Medicare beneficiaries, used surrogate markers of effectiveness, or did not meet all primary end points. As more breakthrough devices receive FDA authorization and effectively qualify for automatic supplemental payments, strengthening premarket clinical evidence requirements for CMS TPTP approvals would provide better information to guide clinical decision-making and ensure that supplemental reimbursement enhances care for Medicare beneficiaries.

Miniaturized circularly polarized wearable array antenna for medical device applications

Antenna miniaturization is essential for healthcare applications, and numerous studies have tackled the challenge of presenting miniaturized, reliable designs while maintaining performance. This paper presents a small circularly polarized (CP) sequential wearable array antenna with overall dimensions of only 110 mm × 95 mm × 1.8 mm. It comprises four novel designs of circular-shaped elements arranged sequentially in an array configuration measured only 24 mm×24 mm×1 mm. It is fed by a separate cascade feeding network incorporating a single rat-race and two branch-line couplers. The antenna is designed for medical device applications within the 2.4 GHz Industrial Scientific Medical (ISM) frequency band. The proposed design is fabricated and experimentally tested, demonstrating wide impedance bandwidths of 21.24% (2.2–2.72 GHz) and an Axial Ratio (AR) bandwidth (AR < 3 dB) covering the entire 2.4 GHz ISM frequency band. At 2.43 GHz, the antenna achieves a gain of -14.9 dBi. Both simulation and experimental results confirm excellent performance in impedance matching, gain pattern, and circular polarization, making it promising for wearable wireless communication in medical applications. The link margin was calculated, and the specific absorption rate of the antenna was analyzed, the result revealing that it aligns with the safety limits of IEEE C95.1-1999 standards.

Stability‐Enhanced Variable Stiffness Metamaterial with Controllable Force‐Transferring Path

AbstractSelf‐contact variable stiffness (SVS) metamaterial offers specific patterns of elastic strain energy storage by changing its force‐transferring path. The change of the elastic strain energy storage patterns further influences the stiffness variation of the SVS metamaterials. However, challenges still arise because typically fabricated SVS metamaterials inevitably contain structural irregularities, eccentricities, and defects. These microstructural imperfections impede the stable generation of designed strain energy storage patterns in the metamaterial, implying that the SVS metamaterials cannot achieve expected stiffness variations. To address this burning question, an SVS metamaterial/meta‐structure design paradigm with eccentric unit designs is proposed, which can realize both stable stiffness variations and high load‐bearing. The theoretical, simulation, and experimental results demonstrate that the SVS chain meta‐structure achieves ≈110 times stiffness variation between the low and high loading conditions. Its load‐bearing can reach more than 1500 N when the meta‐structure falls into the high stiffness stage. Furthermore, some typical functions are demonstrated using the stability‐enhanced SVS metamaterial, including customized mechanical protections for human joints and information transformation regulated by remote mechanical input signals. The results can provide a useful solution for generating a more feasible stability‐enhanced SVS metamaterial/meta‐structure and promote their potential applications in aerospace, medical devices, and robotics.

Development of a P(L-D,L)LA Foam as a Dura Substitute and Its In Vitro Evaluation

Dura substitutes are used to reduce the risk of postoperative complications following neurosurgical interventions, and to facilitate the healing of dura damages or defects caused by injuries. Traditional tissue transplants have limitations like limited tissue availability, potential risk of immune rejection and disease transmission. The use of biomaterials composed of synthetic polymers as dura substitutes offers a promising approach to overcome these limitations to replace and treat damaged dura mater. Potential biocompatible porous scaffolds still need to be developed to minimize the risks of immune response and disease transmission, while also ensuring effective cell migration and cell ingrowth in three dimension. The aim of the present study was to develop a poly(L-lactide-co-D,L-lactide) (P(L-D,L)LA) foam with an optimal pore size for dura mater substitution, investigate its morphological characteristics, and evaluate its potential for dura mater regeneration by assessing the spreading and growth of meningeal cells within it through in vitro studies. Foams were produced by lyophilization using different concentrations of P(L-D,L)LA solution. A GMP-grade P(L-D,L)LA, suitable for medical device applications, was used in this study. Morphological analysis was performed using scanning electron microscopy, and porosity of the foams was studied with mercury porosimetry. In in vitro studies, meningeal cells were seeded onto the polymeric foams, and their behavior and proliferation in these scaffolds were investigated with cytoskeleton and nucleus staining, and colorimetric cell proliferation assay, respectively. Scanning electron microscopy results showed that the foams prepared with 2.5% and 3% polymer solutions displayed good structural integrity and convenient interconnectivity, with pore sizes ranging from 80 to 150 µm. However, the foams prepared with 2% and 4% polymer solution demonstrated poor structural integrity and low interconnectivity, respectively. In vitro studies showed that the foams prepared with 2.5% and 3% polymer solutions served effectively as scaffolds for meningeal cells, and the cells attached, spread and homogeneously distributed. In addition, the cells proliferated and increased in number over time within these polymeric scaffolds. These findings suggest that the foams produced with 2.5% and especially 3% P(L-D,L)LA polymer solutions could effectively serve as a suitable substitute for the dura mater, providing an appropriate environment for cell ingrowth and tissue integration. This indicates that the developed foam could be a promising treatment for dura mater damage or defects, with the potential approach to promote regeneration in future in vivo and clinical studies.

Adaptive bioinspired morphing surface using temperature-responsive elastomer-SMA composites

The pursuit of "smart" materials, drawing inspiration from biological organisms, has been a significant focal point in the realm of material science and engineering. Shape memory materials, notably Shape Memory Alloys (SMAs), have emerged as promising platforms for the development of adaptive and responsive materials that undergo transformations in response to environmental stimuli. This article explores the creation of a bioinspired morphing surface that capitalizes on the innovative amalgamation of Ecoflex and Nitinol (NiTi) wires. Inspired by biological mechanisms, this morphing surface exemplifies remarkable adaptability, seamlessly transitioning from 2D to 3D shapes with precision. A detailed mechanical characterization underscores pivotal changes in material properties, showcasing a significant reaction force increase from 0.4 N to 1 N in NiTi wires at 20 °C and 50 °C. Concurrently, the embedded NiTi wire within the Ecoflex matrix exhibits a similar force increment from 0.6 N to 1.2 N, reflecting the microstructural alterations dependent on temperature. The study also elucidates the versatility and scalability of this technology, highlighting its potential for diverse applications in aerospace, robotics, medical devices, and adaptive materials. This bioinspired morphing surface offers a versatile foundation for customizable shapes and programmable transformations, paving the way for impactful advancements in a multitude of fields.

UV-A Flexible LEDs Based on Core-Shell GaN/AlGaN Quantum Well Microwires.

Nanostructured ultraviolet (UV) light sources represent a growing research field in view of their potential applications in wearable optoelectronics or medical treatment devices. In this work, we report the demonstration of the first flexible UV-A light emitting diode (LED) based on AlGaN/GaN core-shell microwires. The device is based on a composite microwire/poly(dimethylsiloxane) (PDMS) membrane with flexible transparent electrodes. The electrode transparency in the UV range is optimized: namely, we demonstrate that single-walled carbon nanotube electrodes provide a stable electrical contact to the membrane with high transparency (70% at 350 nm). The flexible UV-A membrane demonstrating electroluminescence around 345 nm is further applied to excite Zn-Ir-BipyPDMS luminophores: the UV-A LED is combined with the elastic luminophore-containing membrane to produce a visible amber emission from 520 to 650 nm. The obtained results pave the way for flexible inorganic light-emitting diodes to be employed in sensing, detection of fluorescent labels, or light therapy.

4D printing of magneto-responsive shape memory nano-composite for stents

Abstract This study focuses on the 4D printing simulation technique of magneto-responsive shape memory nanocomposite stents. A nanocomposite material was created by incorporating polycaprolactone, a shape memory material, with Fe3O4 to enhance magnetic responsiveness and stiffness. Tensile tests were conducted, and the material properties were applied to finite element analysis. Shape memory experiments were also performed to measure the temperature at which shape memory progression occurs due to magnetic response. In the 4D printing simulation, different coefficients of thermal expansion and the measured temperatures were reflected in the sections where shape memory is activated to implement shape memory behavior. The specimen simulation confirmed shape memory behavior progressing from 145 degrees to 3 degrees, while the stent simulation demonstrated satisfactory expansion to a radius of 3 mm. This study proposes a controllable method for implementing shape memory considering temperatures induced by magnetic response, showing potential for various medical device applications.

Current Application of the Medical Device Single Audit Program (MDSAP) as a Global Regulatory Reliance Framework for the Inspection of Medical Devices.

The globalization and rapid advancements in medical technologies necessitate the harmonization of international regulatory frameworks to ensure the efficient and timely clinical application of medical products, including pharmaceuticals and medical devices. Regulatory reliance, a critical component of this harmonization process, is a powerful tool that provides efficient access for economic entities and regulatory authorities, promoting predictable decision-making and accelerating approvals. The Medical Device Single Audit Program (MDSAP) serves as a regulatory reliance framework for medical device inspections. Implemented by countries including Japan, the United States, Canada, Australia, and Brazil, MDSAP allows third-party certification bodies, recognized by these regulatory authorities, to conduct audits on medical device manufacturers. The outcomes of these audits are shared with the regulatory authorities, who use them for regulatory assessments and decision-making. Since transitioning to its implementation phase in 2017, MDSAP has been widely utilized in various countries. This review provides an overview of the adoption and utilization of MDSAP in major countries, exploring the program's impact on regulatory processes and its potential as a method of regulatory reliance to facilitate timely access to effective and safe medical devices.

Assessing the Correlation Between the Physico-Mechanical Characteristics and Microstructure of Reclaimed Carbon Dust Reinforced ABS Polymer Composite in the Extrusion Process

ABS polymer has limited stiffness and will fracture upon reaching this limit. Reinforcing ABS with reclaimed carbon dust (rCD) from CFRP waste, which has superior stiffness in both compression and tension, can prevent this failure. This study evaluates the impact of varying rCD filler content and screw extruder speeds on the physico-mechanical properties of the composite. rCD content ranges from 0 wt.% to 40 wt.% and screw speeds of 20 rpm and 40 rpm are used. The rCD was sieved and its quality was verified using particle size analysis (PSA), field emission scanning electron microscopy with energy dispersive X-ray (FESEM-EDX), and X-ray diffraction (XRD) before composite fabrication in a single screw extruder. The physico-mechanical properties, including tensile strength, Young’s modulus, and density, were tested using a universal testing machine (UTM) and Archimedes technique. All samples appeared undistorted prior to UTM evaluation. Results indicated that composites processed at 40 rpm with 40 wt.% rCD exhibited superior physico-mechanical properties compared to those processed at 20 rpm. Fractography of tensile fracture samples showed well-dispersed rCD within the ABS matrix, with minimal large pores at 40 rpm. Additionally, the highest tensile strength (31.48 MPa) and Young’s modulus (1.603 GPa) indicated good dispersion of rCD and strong interfacial bonding between the matrix and fiber. Thus, a 40 rpm screw speed is more effective for mixing ABS/rCD composites. In conclusion, rCD was successfully reclaimed and integrated into ABS, resulting in a composite with enhanced strength properties suitable for assistive medical device application.

Water-mediated chelation dynamics of dicarboxylic acid functionalized TiO2 nanoparticles for β-nucleation enhancement in isotactic polypropylene composites

ABSTRACT Isotactic polypropylene (iPP) is the most prominent form of polypropylene, and β-phase is the most resistant to impact compared to the crystalline forms. However, β-phase is the least frequently obtained under conventional operating conditions. TiO2 nanoparticles were functionalized with dicarboxylic acids as nucleating agents to promote β-crystal formation in iPP. The effects of three dicarboxylic acids – glutaric, pimelic, and azelaic – were characterized on TiO2-modified surfaces. Additionally, the interactions between TiO2 and water molecules, crucial for the formation of chelating or bridging linkages, were analyzed using Fourier Transform Infrared spectroscopy. For pimelic and azelaic acids at the polymer processing temperature, the carboxyl group band disappeared, suggesting a transition of the acid-calcium union from a bridging to a chelating linkage due to the presence of water molecules. These molecules help maintain the stability of the chains during processing. X-ray diffraction (XRD) analysis confirmed a higher content of β-crystalline structures in iPP when modified with pimelic and azelaic acids. The research indicates that water molecules, desorbed during manufacturing, facilitate the chelating form, thereby enhancing β-nucleation and improving the surface properties of iPP composites. These β-nucleated PP composites represent a promising material solution for medical device applications, offering a compelling combination of enhanced properties and cost-effectiveness.

Extraction of basil seed gum: Optimization and functional properties

Basil seed gum (BSG), a natural vegetable gum, was extracted by ethanol precipitation method using basil seeds as raw material. Based on the single factor experiments, Box-Behnken response surface test was performed to optimize the extraction conditions, and the physicochemical and functional properties of the extracted basil seed gum, as well as its microstructure, were analyzed in detail. The results showed that the optimal extraction conditions of basil seed gum were as follows: liquid-to-feed ratio of 62:1, temperature of 50 °C, extraction time of 29.50 min, and pH = 8.1, with yield of 11.28 %. BSG was mainly composed of total sugars (93.09 %), uronic acid (18.83 %), proteins (2.77 %), and ash (4.35 %), and its monosaccharides included D-(+)-anhydrous glucose (58.26 %), D-galactose (21.40 %), D-mannose (11.96 %), D-(+)-galacturonic acid (7.82 %), D-arabinose (0.28 %), D-(+)-xylose (0.28 %), and L-rhamnose (0.002 %). Comparative analysis of the functional properties of basil seed gum and three commercial vegetable gums (linseed gum, caraway seed gum, guar gum) showed that basil seed gum had excellent water retention properties, and its water absorption and water holding properties were much better than those of three commercial gums. Rheological characterization showed that BSG was a pseudoplastic fluid with high zero-shear viscosity. In addition, the basil seed gum powder showed an irregular flaky fibrous structure under microscope and was a semi-crystalline polymer. In view of the high aqueous absorption and retention properties of basil seed gum, it has promising applications in food, cosmetic and medical devices.

Integrated 3D printing of reconfigurable soft machines with magnetically actuated crease-assisted pixelated structures

Reconfigurable magnetic soft machines have a wide range of applications in soft robotics, aerospace, medical devices and flexible electronics. However, the high-precision reconfiguration of magnetically actuated soft machines is hindered by the absence of rational structural design and integrated manufacturing techniques. Here, we report an innovative design and manufacturing approach to realize magnetically actuated high-precision reconfigurability. We present a crease-assisted pixelated design using a mixture of magnetic particles and phase-change medium as the pixel points, with an elastomer as the crease to connect the pixel points, simulating origami. The design of elastomer creases improves pixel stiffness without loss of reconfigurable accuracy, thereby significantly improves the magnetic particle concentration in the pixel. An effective multi-material 3D printing technique is used to achieve the integrated printing of the designed structure. The resulting magnetically actuated soft machines exhibit remarkable capabilities, achieving small curvature bending and precise reconfiguration with weaker actuating magnetic fields (100mT). The superior performance of this design has been confirmed through demonstrations of crawling and rolling machines, magnetically controlled switches, and logic circuits. The work enhances the reconfiguration accuracy of magnetically actuated soft machines, increasing their potential for soft robotics and flexible electronics applications.

Synergistic Strategies of Biomolecular Transport Technologies in Transdermal Healthcare Systems.

Transdermal healthcare systems have gained significant attention for their painless and convenient drug administration, as well as their ability to detect biomarkers promptly. However, the skin barrier limits the candidates of biomolecules that can be transported, and reliance on simple diffusion poses a bottleneck for personalized diagnosis and treatment. Consequently, recent advancements in transdermal transport technologies have evolved toward active methods based on external energy sources. Multiple combinations of these technologies have also shown promise for increasing therapeutic effectiveness and diagnostic accuracy as delivery efficiency is maximized. Furthermore, wearable healthcare platforms are being developed in diverse aspects for patient convenience, safety, and on-demand treatment. Herein, a comprehensive overview of active transdermal delivery technologies is provided, highlighting the combination-based diagnostics, therapeutics, and theragnostics, along with the latest trends in platform advancements. This offers insights into the potential applications of next-generation wearable transdermal medical devices for personalized autonomous healthcare.

Monitoring System of Medical Device Adverse Events in the US and Application of MAUDE Database in Medical Device Registration

In order to achieve precise risk control of medical devices, it is necessary to establish a scientific evaluation system throughout the entire life cycle of medical devices that focuses on risk identification and risk control. This study summarizes the medical device adverse event monitoring system of the US on regulatory agencies and regulatory law, adverse events reporting forms and time limits, adverse event database, adverse event report analysis and evaluation, as well as adverse event feedback and control. Furthermore, some examples are provided to illustrate the application of the MAUDE database in risk analysis, physical and mechanical performance research, and clinical evaluation of medical device registration and application materials.

Stability Enhancement by Hydrophobic Anchoring and a Cross-Linked Structure of a Phospholipid Copolymer Film for Medical Devices.

Surface modification using zwitterionic 2-methacryloyloxyethylphosphorylcholine (MPC) polymers is one of the most reasonable ways to prepare medical devices that can suppress undesired biological reactions such as blood coagulation. Usable MPC polymers are hydrophilic and water soluble, and their surface modification strategy involves exploiting the copolymer structures by adding physical or chemical bonding moieties. In this study, we developed copolymers composed of MPC, hydrophobic anchoring moiety, and chemical cross-linking unit to clarify the role of hydrophobic interactions in achieving biocompatible and long-term stable coatings. The four kinds of MPC copolymers with cross-linking units, such as 3-methacryloxypropyl trimethoxysilane (MPTMSi), and four different hydrophobic anchoring moieties, such as 3-(methacryloyloxy)propyltris(trimethylsiloxy)silane (MPTSSi) named as PMMMSi, n-butyl methacrylate (BMA) as PMBSi, 2-ethylhexyl methacrylate (EHMA) as PMESi, and lauryl methacrylate as PMLSi, were synthesized and coated on polydimethylsiloxane, polypropylene (PP), and polymethyl pentene. These copolymers were uniformly coated on the substrate materials PP and poly(methyl pentene) (PMP), to achieve hydrophilic and electrically neutral coatings. The results of the antibiofouling test showed that PMBSi repelled the adsorption of fluorescence-labeled bovine serum albumin the most, whereas PMLSi repelled it the least. Notably, all four copolymers suppressed platelet adhesion similarly. The variations in protein adsorption quantities among the four copolymer coatings were attributed to their distinct swelling behaviors in aqueous environments. Further investigations, including 3D scanning force microscopy and neutron reflectivity measurements, revealed that the PMLSi coating exhibited a higher water intake under aqueous conditions in comparison to the other coatings. Consequently, all copolymer coatings effectively prevented the invasion of platelets but the proteins penetrated the PMLSi network. Subsequently, the dynamic stability required to induce shear stress was evaluated using a circulation system. The results demonstrated that the PMMMSi and PMLSi coatings on PMP and PP exhibited exceptional platelet repellency and maintained high stability during circulation. This study highlights the potential of hydrophobic moieties to improve hemocompatibility and stability, offering potential applications in medical devices.

The Horizons of Medical Mineralogy: Structure-Bioactivity Relationship and Biomedical Applications of Halloysite Nanoclay.

Medical mineralogy explores the interactions between natural minerals and living organisms such as cells, tissues, and organs and develops therapeutic and diagnostic applications in drug delivery, medical devices, and healthcare materials. Many minerals (especially clays) have been recognized for pharmacological activities and therapeutic potential. Halloysite clay (Chinese medicine name: Chishizhi), manifested as one-dimensional aluminum silicate nanotubes (halloysite nanotubes, HNTs), has gained applications in hemostasis, wound repair, gastrointestinal diseases, tissue engineering, detection and sensing, cosmetics, and daily chemicals formulations. Various biomedical applications of HNTs are derived from hollow tubular structures, high mechanical strength, good biocompatibility, bioactivity, and unique surface characteristics. This natural nanomaterial is safe, abundantly available, and may be processed with environmentally safe green chemistry methods. This review describes the structure and physicochemical properties of HNTs relative to bioactivity. We discuss surface area, porosity and surface defects, hydrophilicity, heterogeneity and charge of external and internal surfaces, as well as biosafety. The paper provides comprehensive guidance for the development of this tubule nanoclay and its advanced biomedical applications for clinical diagnosis and therapy.

Review of Microwave Near-Field Sensing and Imaging Devices in Medical Applications.

Microwaves can safely and non-destructively illuminate and penetrate dielectric materials, making them an attractive solution for various medical tasks, including detection, diagnosis, classification, and monitoring. Their inherent electromagnetic properties, portability, cost-effectiveness, and the growth in computing capabilities have encouraged the development of numerous microwave sensing and imaging systems in the medical field, with the potential to complement or even replace current gold-standard methods. This review aims to provide a comprehensive update on the latest advances in medical applications of microwaves, particularly focusing on the near-field ones working within the 1-15 GHz frequency range. It specifically examines significant strides in the development of clinical devices for brain stroke diagnosis and classification, breast cancer screening, and continuous blood glucose monitoring. The technical implementation and algorithmic aspects of prototypes and devices are discussed in detail, including the transceiver systems, radiating elements (such as antennas and sensors), and the imaging algorithms. Additionally, it provides an overview of other promising cutting-edge microwave medical applications, such as knee injuries and colon polyps detection, torso scanning and image-based monitoring of thermal therapy intervention. Finally, the review discusses the challenges of achieving clinical engagement with microwave-based technologies and explores future perspectives.

Multiaxial filament winding of biopolymer microfibers with a collagen resin binder for orthobiologic medical device biomanufacturing

Multiaxial filament winding is an additive manufacturing technique used extensively in large industrial and military manufacturing yet unexplored for biomedical uses. This study adapts filament winding to biomanufacture scalable, strong, three-dimensional microfiber (3DMF) medical device implants for potential orthopedic applications. Polylactide microfiber filaments were wound through a collagen ‘resin’ bath to create organized, stable orthobiologic implants, which are sized for common ligament (e.g. anterior cruciate ligament) and tendon (e.g. rotator cuff) injuries and can be manufactured at industrial scale using a small footprint, economical, high-output benchtop system. Ethylene oxide or electron beam sterilized 3DMF samples were analyzed by scanning electron microscopy (SEM), underwent ASTM1635-based degradation testing, tensile testing, ISO 10993-based cytocompatibility, and biocompatibility testing, quantified for human platelet-rich plasma (PRP) absorption kinetics, and examined for adhesion of bioceramics and lyophilized collagen after coating. 3DMF implants had consistent fiber size and high alignment by SEM. Negligible mass and strength loss were noted over 4 months in culture. 3DMF implants initially exceeded 1000 N hydrated tensile strength and retained over 70% strength through 4 months in culture, significantly stronger than conventionally produced implants made by fused fiber deposition 3D printing. 3DMF implants absorbed over 3x their weight in PRP within 5 min, were cytocompatible and biocompatible in vivo in rabbits, and could readily bind tricalcium phosphate and calcium carbonate coatings discretely on implant ends for further orthobiologic material functionalization. The additive manufacturing process further enabled engineering implants with suture-shuttling passages for facile arthroscopic surgical delivery. This accessible, facile, economical, and rapid microfiber manufacturing platform presents a new method to engineer high-strength, flexible, low-cost, bio-based implants for orthopedic and extended medical device applications.