This study presents a comprehensive experimental investigation into the impact resistance of stacked composite structures fabricated by hybridizing 3D-printed carbon fiber-reinforced polyether ether ketone (CF-PEEK) with perforated aluminum (Al 3004) foil layers. Both perforated and unperforated Al foil, strategically interleaved within CF-PEEK layers and bonded using epoxy resin. Two critical fabrication parameters fiber orientation (0°, 45°, and 90°) and layer height (0.2 mm, 0.3 mm, and 0.4 mm) were systematically varied using a full factorial design to assess their influence on impact performance. Charpy impact tests were conducted in accordance with ASTM D6110 on both hybrid CF-PEEK/Al foil laminates and CF-PEEK-only specimens. Results indicated a substantial improvement in impact energy absorption and impact strength for the hybrid configurations, with peak values reaching up to 30 J and 402.2 J/m2, respectively at a fiber orientation of 90° and a layer height of 0.2 mm. In contrast, corresponding CF-PEEK-only specimens exhibited significantly lower energy absorption, with maximum values of 17 J and 227.9 J/m2 under the same conditions. Among all parameter combinations, the hybrid specimens with a fiber orientation of 45° and a layer height of 0.3 mm demonstrated the most consistent and enhanced performance. These findings highlight the synergistic effect of metallic reinforcement and optimized printing parameters improves mechanical robustness of additively manufactured composite laminates. This work emphasizes the potential of hybrid additive manufacturing (HAM) approaches in developing lightweight, high-strength materials for aerospace, defense, and impact-critical applications, offering a promising pathway for tailoring structural performance through designable interfacial architectures and controlled fabrication parameters.
- Keywords
- 3D printing, Additive manufacturing, Aluminum foil, CF-PEEK composites, FFF, Fiber orientation, Hybrid laminates, Impact resistance, Layer height, Perforated aluminum foil,
- Publication type
- Journal Article MeSH
In the field of orthopedic surgery, large bone defects resulting from trauma, surgical resection, or congenital anomalies present significant challenges. In many cases, treatment necessitates scaffold structures that not only support bone regeneration but also address potential bacterial infections that can impede healing. In this study, we developed 3D bioprinted scaffolds using hydrogel-based biomaterial ink comprising a blend of chitosan (CS) and agarose (AG), each separately fortified with ZnO, MgO, and CaO nanoparticles (NPs). We performed a comprehensive assessment of the inks' printability and wettability, and ascertained their rheological properties. The in vitro degradation of 3D bioprinted scaffolds was analyzed, their antibacterial capabilities against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) were explored, and the differentiation of bone marrow mesenchymal stem cells (BMSCs) was evaluated. The findings indicated that the hydrogel, CS-AG (CA), composed of 3.5% (w/v) CS and 1.5% (w/v) AG, demonstrated superior printing characteristics. Among the nanoparticles, ZnO proved to be a notable booster of antibacterial activity and facilitated osteogenic differentiation and proliferation of bone marrow stem cells. Conversely, MgO showed similar antibacterial efficacy but was less successful in promoting cell proliferation compared to ZnO and CaO, whereas CaO displayed the weakest antibacterial efficacy. The results identify the ZnO NP-loaded CA biomaterial ink as a viable option for addressing bone abnormalities, enhancing bone repair, and preventing bacterial infection.
Chronic wounds remain one of the significant burdens to health across the world, mainly in view of diabetes and its natural consequences. This category of lesions includes pressure ulcers, vascular diseases, and surgery-related wounds, which affect millions and pose a major challenge to the healthcare industry. The paper reviews the various physiological mechanisms of wound healing, factors that impede it, and some new treatments emerging at this moment. In contrast, current developments include surgical and non-surgical alternatives like topical dressings, medicated formulations, and skin substitutes. Advanced wound care today covers tissue-engineered skin substitutes, 3D-printed wound dressings, topical medicated formulations, and growth factor-based therapies. These are non-invasive, biocompatible methods that are cost-effective, userfriendly, and more conducive to natural healing than traditional therapies. Hydrogel dressings have high water content to create a moist environment that encourages healing. They also reflect excellent physicochemical and biological properties, which enhance autolytic debridement and reduction of pain due to the moisture retention, biocompatibility, and non-toxicity conferred. Tissue-engineered skin substitutes, comprising allogeneic or autologous cells, wound-healing enhancement bioengineered allogeneic cellular therapies are like the natural skin and encourage regeneration. 3D printing allows the production of customized dressings to aid in better treatment. Newer therapies, including bioengineered allogeneic cellular therapies and fish skin grafting, require more clinical trials to confirm safety and efficacy. With such innovations in wound healing technologies and therapies, the future looks quite promising in managing chronic wounds, enhancing healing, reducing healthcare expenditure, and promoting a better quality of life for patients.
- Keywords
- 3D printing, Wound healing, chronic wounds., emerging therapies, fish skin grafting, tissue regeneration,
- MeSH
- Printing, Three-Dimensional MeSH
- Chronic Disease MeSH
- Wound Healing * drug effects MeSH
- Humans MeSH
- Bandages MeSH
- Wounds and Injuries * therapy MeSH
- Tissue Engineering MeSH
- Skin, Artificial MeSH
- Animals MeSH
- Check Tag
- Humans MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Review MeSH
This paper presents development and application of a Fiber Bragg Grating (FBG) array embedded in a 3D-printed insole for ground reaction force (GRF) estimation. In this case, a 3D-printed insole is fabricated from a scanned commercial insole in which a 5-FBGs array is integrated. The FBGs are characterized as a function of the applied transverse force, where a mean sensitivity of 0.11 ± 0.10 pm/N was obtained considering all FBGs. A portable FBG signal acquisition system was connected to the FBG array embedded in the insole and tested for the GRF analysis in a healthy volunteer. The gait tests results indicate stance and swing phases of 41.0 ± 6.5% and 59 ± 6.5%, respectively, which are within reference values of the literature. Furthermore, a 0.904 R2 was found in the correlation analysis of the measured GRF response and the conventional M-shaped curve for the GRF in which all subdivisions of the stance phase were detected.
- Keywords
- fiber bragg gratings, ground reaction forces, instrumented insoles, wearable sensing,
- MeSH
- Printing, Three-Dimensional * MeSH
- Biosensing Techniques * MeSH
- Gait MeSH
- Humans MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
Among the many applications of additive technologies, their use in drug formulation holds a particularly important place. Numerous studies have been conducted on using various 3D printing techniques to produce both immediate- and modified-release dosage forms. However, the drug release mechanism may vary depending on the manufacturing method and formulation composition. This work aimed to analyze the influence of the 3D printing method used on the mechanism of fluconazole release from prolonged-release tablets. We conducted an analysis of tablets containing 50 mg of fluconazole, produced using two 3D printing techniques: Fused Deposition Modeling (FDM) and Liquid Crystal Display (LCD, classified as one of the Vat Photopolymerization (VPP) methods). Because FDM and VPP techniques build objects in fundamentally different ways, a unique set of excipients was used for each of these methods. For the FDM-printed tablets, poly(vinyl alcohol) was used to control drug release and as the filament-forming polymer. The tablet matrix produced using the VPP method was based on the cross-linked polyethylene glycol diacrylate. Both formulations were characterized by prolonged release of API. Employing surface dissolution imaging and kinetic models, we demonstrated that in the case of FDM-printed tablets, the API release is mainly regulated by the relaxation and gradual decay of the water-soluble polymer. In contrast, the relaxation of the water-insoluble matrix of VPP tablets was negligible. Although the diameter of the VPP tablets increased slightly during the dissolution study, the API release was primarily controlled by the diffusion of fluconazole through the cross-linked polymer.
- Keywords
- Drug release, Fluconazole, Fused deposition modeling, Intrinsic dissolution rate, Kinetic Models, Liquid crystal display, Surface dissolution imaging,
- Publication type
- Journal Article MeSH
In this study, the potential use of low methylated amidated pectin for the preparation of hydrogel bioinks was investigated. The pectins used were derived from various fruits and were characterized by differences in molecular weight, monosaccharide composition, degree of esterification, degree of amidation and the type of sugar additive (sucrose or glucose). The focus was on analyzing the influence of polymer structure and sugar type on the 3D printability and thermal properties of the developed formulations. The results showed that the type and amount of sugar seem to be the most crucial factors. It was observed that in the presence of sucrose, pectin crosslinking occurs not only through ionic and hydrogen interactions (sugar-pectin-metal ion), but also through chemical crosslinking, most likely as a result of the Millard reaction between amidated pectin and fructose formed via sucrose hydrolysis. This phenomenon is not observed in the presence of glucose in the system, where the polymer forms reversible gels. Printability tests indicated that using biopolymer standardized with glucose and optimizing its amount in the system is beneficial to obtain inks based on amidated pectin with a low degree of esterification.
- Keywords
- 3D printing, Amidation, Hydrogel analysis, Low methylated pectin, Polymer structure, Sugar,
- Publication type
- Journal Article MeSH
This study presents a rapid, environmentally friendly, and scalable activation method for 3D-printed poly-(lactic acid)/carbon black (PLA/CB) electrodes using atmospheric air plasma under ambient conditions. The goal was to optimize the plasma activation time and compare its efficiency with conventional activation techniques using N,N-dimethylformamide (DMF) and sodium hydroxide (NaOH). Surface morphology, chemical composition, wettability, and electrochemical performance were systematically evaluated through scanning electron microscopy (SEM), Raman spectroscopy, XPS, contact angle measurements, cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). Plasma treatment, as short as 5 s, effectively removed the PLA matrix from the electrode surface, enhanced surface roughness, hydrophilicity, and exposure of conductive carbon black particles, leading to increased electrochemical performance. Compared to chemical activation, 40 s of plasma activation yielded comparable performance with significantly shorter processing times (vs NaOH) and without hazardous solvents (such as DMF). Finally, the activated electrodes were successfully applied in the development, optimization, and validation of a novel electrochemical protocol for the determination of the antihypertensive drug amlodipine, revealing high sensitivity, a low limit of detection of 0.09 μM, precision (RSD of 6.6%), and recovery (97.1 and 105.4%) in pharmaceutical formulations. The findings demonstrate the promising potential of air plasma activation as a sustainable and efficient approach for preparing 3D-printed electrodes for analytical and sensing applications.
- Publication type
- Journal Article MeSH
Extensive peripheral nerve injuries often lead to the loss of neurological function due to slow regeneration and limited recovery over large gaps. Current clinical interventions, such as nerve guidance conduits (NGCs), face challenges in creating biomimetic microenvironments that effectively support nerve repair. The developed GrooveNeuroTube is composed of hyaluronic acid methacrylate and gelatin methacrylate hydrogel, incorporating active agents (growth factors and antibacterial agents) encapsulated within an NGC conduit made of 3D-printed PCL grid fibers. In vitro studies showed that GrooveNeuroTube significantly promoted migration of dorsal root ganglion (DRG) neuronal cells, 3D bioprinted at the far ends of the conduit to imitate a proximal nerve injury as a novel ex vivo model. A long-term culture of up to 60 days was employed to better mimic in vivo conditions. This model tested the effects of pulsed electromagnetic field (PEMF) stimulation on neural tissue development. After 60 days, GrooveNeuroTube showed a 32% cell migration increase compared to the growth-factor-group and 105% compared to the no-growth-factor condition. These results confirm that the GrooveNeuroTube system can effectively support sustained neural cell migration and maturation over extended periods, proving a new technology for testing peripheral nerve injury ex vivo. .
- Keywords
- 3D bioprinting, biofabrication, gelatin methacrylate, hyaluronic acid, nerve guidance conduits, neural migration, neurite outgrowth,
- Publication type
- Journal Article MeSH
The complexity and spatial relationships between vascular and cardiac structures, as well as anatomical diversity, pose a challenge for planning and performing cardiac interventions. Medical imaging, especially precise three-dimensional imaging techniques, plays a key role in the decision-making process. While traditional imaging methods like angiography, echocardiography, computed tomography, and magnetic resonance imaging remain gold standards, they have limitations in representing spatial relationships effectively. To overcome these limitations, advanced techniques such as three-dimensional printing, three-dimensional modelling, and Extended Realities are needed. Focusing on Extended Realities, their main advantages are direct spatial visualization based on medical data, interaction with objects, and immersion in cardiac anatomy. These benefits impact procedural planning and intra-procedural navigation. The following publication presents current applications, benefits, drawbacks, and limitations of Virtual, Augmented, and Mixed Reality technologies in cardiac interventions. The aim of this review is to improve understanding and utilization of the entire spectrum of these innovative tools in clinical practice.
- Keywords
- 3D imaging, Augmented reality, Cardiac imaging, Extended Realities, Intra-procedural navigation, Mixed reality, Pre-procedural planning, Virtual reality,
- Publication type
- Journal Article MeSH
Materials based on polylactic acid (PLA) are now extensively utilized across various fields, including biomedical engineering, where they are increasingly favored for the development of implantable devices and tissue replacements. Due to its ease of melting, PLA is also among the most commonly used materials in 3D printing. This makes PLA-based materials highly attractive for the production of customized implants and personalized medical devices. To support the design of such components, the computer simulations involved must rely on reliable constitutive models. The current approaches for PLA-based 3D printed material models include linear elasticity, linear viscoelasticity or elastoplasticity, hyperelasticity, and advanced nonlinear theories dealing with irreversible processes. While linear theories are undoubtedly simplistic, nonlinear models frequently result in complex descriptions which are dependent on too many material parameters. In this context, our study aims to show the ability of the Quasi-Linear Theory of Viscoelasticity to accurately reproduce the tensile test results for PLA-based materials produced using Fused Deposition Modeling. We will demonstrate this with tensile test results performed on PLA-PHB strips with TAC added as a plasticizer. The nonlinear stress-strain curves obtained from the experiments were successfully fitted by using a model compatible with finite strain theory, comprising only three material parameters. One of these parameters relates to equilibrium elasticity, while the other two correspond to the Maxwell element, which describes dissipative behavior. These results highlight the potential of this modeling approach to capture the essential aspects of the mechanical response using a minimal parameter set, which offers a promising balance between simplicity and predictive power for applications in simulation-based design.
- Keywords
- Additive manufacturing, Constitutive model, Polyhydroxybutyrate, Polylactic acid, QLV, Tensile test,
- MeSH
- Printing, Three-Dimensional * MeSH
- Biocompatible Materials * chemistry MeSH
- Stress, Mechanical MeSH
- Tensile Strength MeSH
- Polyesters * chemistry MeSH
- Elasticity MeSH
- Materials Testing MeSH
- Viscosity MeSH
- Publication type
- Journal Article MeSH
- Names of Substances
- Biocompatible Materials * MeSH
- poly(lactide) MeSH Browser
- Polyesters * MeSH