Search Results (652)

Background: Precision medicine refers to the formulation of personalized drug regimens according to the individual characteristics of patients to achieve optimal efficacy and minimize adverse reactions. Additive manufacturing (AM), also known as three-dimensional (3D) printing, has emerged as an optimal solution for precision drug delivery, enabling customizable and the fabrication of multifunctional structures with precise control over morphology and release behavior in pharmaceutics. However, the influence of 3D printing parameters on the printed tablets, especially regarding in vitro and in vivo performance, remains poorly understood, limiting the optimization of manufacturing processes for controlled-release profiles. Objective: To establish the fabrication process of 3D-printed controlled-release tablets via comprehensively understanding the printing parameters using fused deposition modeling (FDM) combined with hot-melt extrusion (HME) technologies. HPMC-AS/HPC-EF was used as the drug delivery matrix and carbamazepine (CBZ) was used as a model drug to investigate the in vitro drug delivery performance of the printed tablets. Methodology: Thermogravimetric analysis (TGA) was employed to assess the thermal compatibility of CBZ with HPMC-AS/HPC-EF excipients up to 230 °C, surpassing typical processing temperatures (160–200 °C). The formation of stable amorphous solid dispersions (ASDs) was validated using differential scanning calorimetry (DSC), hot-stage polarized light microscopy (PLM), and powder X-ray diffraction (PXRD). A 15-group full factorial design was then used to evaluate the effects of the fan speed (20–100%), platform temperature (40–80 °C), and printing speed (20–100 mm/s) on the tablet properties. Response surface modeling (RSM) with inverse square-root transformation was applied to analyze the dissolution kinetics, specifically t_50% (time for 50% drug release) and Q_4h (drug released at 4 h). Results: TGA confirmed the thermal compatibility of CBZ with HPMC-AS/HPC-EF, enabling stable ASD formation validated by DSC, PLM, and PXRD. The full factorial design revealed that printing speed was the dominant parameter governing dissolution behavior, with high speeds accelerating release and low speeds prolonging release through porosity-modulated diffusion control. RSM quadratic models showed optimal fits for t_50% (R² = 0.9936) and Q_4h (R² = 0.9019), highlighting the predictability of release kinetics via process parameter tuning. This work demonstrates the adaptability of polymer composite AM for tailoring drug release profiles, balancing mechanical integrity, release kinetics, and manufacturing scalability to advance multifunctional 3D-printed drug delivery devices in pharmaceutics. Full article

Gene therapy is a groundbreaking strategy in regenerative medicine, enabling precise cellular behavior modulation for tissue repair. In situ nucleic acid delivery systems aim to directly deliver nucleic acids to target cells or tissues to realize localized genetic reprogramming and avoid issues like donor cell dependency and immune rejection. The key to success relies on biomaterial-engineered delivery platforms that ensure tissue-specific targeting and efficient intracellular transport. Viral vectors and non-viral carriers are strategically modified to enhance nucleic acid stability and cellular uptake, and integrate them into injectable or 3D-printed scaffolds. These scaffolds not only control nucleic acid release but also mimic native extracellular microenvironments to support stem cell recruitment and tissue regeneration. This review explores three key aspects: the mechanisms of gene editing in tissue repair; advancements in viral and non-viral vector engineering; and innovations in biomaterial scaffolds, including stimuli-responsive hydrogels and 3D-printed matrices. We evaluate scaffold fabrication methodologies, nucleic acid loading–release kinetics, and their biological impacts. Despite progress in spatiotemporal gene delivery control, challenges remain in balancing vector biocompatibility, manufacturing scalability, and long-term safety. Future research should focus on multifunctional “smart” scaffolds with CRISPR-based editing tools, multi-stimuli responsiveness, and patient-specific designs. This work systematically integrates the latest methodological advances, outlines actionable strategies for future investigations and advances clinical translation perspectives beyond the existing literature. Full article

Recent advancements in polymer science have catalyzed a transformative shift in biomedical engineering, particularly through the development of biodegradable and smart polymers. This review explores the evolution, functionality, and application of these materials in areas such as tissue scaffolding, cardiovascular occluders, and controlled drug delivery systems. Emphasis is placed on shape-memory polymers (SMPs), conductive polymers, and polymer-based composites that combine tunable degradation, mechanical strength, and bioactivity. The synergy between natural and synthetic polymers—augmented by nanotechnology and additive manufacturing—enables the creation of intelligent scaffolds and implantable devices tailored for specific clinical needs. Key fabrication methods, including electrospinning, freeze-drying, and emulsion-based techniques, are discussed in relation to pore structure and functionalization strategies. Finally, the review highlights emerging trends, including ionic doping, 3D printing, and multifunctional nanocarriers, outlining their roles in the future of regenerative medicine and personalized therapeutics. Full article

Background/Objectives: Recent breakthroughs in three-dimensional (3D) printing and high-resolution imaging have opened up new possibilities in personalized medicine, surgical planning, and forensic reconstruction. This study breaks new ground by evaluating the integration of high-resolution peripheral quantitative computed tomography (HR-pQCT) with multimodal imaging and additive manufacturing to assess a chronic, infected gunshot injury in the knee joint of a red deer. This unique approach serves as a translational model for complex skeletal trauma. Methods: Multimodal imaging—including clinical CT, MRI, and HR-pQCT—was used to characterise the extent of osseous and soft tissue damage. Histopathological and molecular analyses were performed to confirm the infectious agent. HR-pQCT datasets were segmented and processed for 3D printing using PolyJet, stereolithography (SLA), and fused deposition modelling (FDM). Printed models were quantitatively benchmarked through 3D surface deviation analysis. Results: Imaging revealed comminuted fractures, cortical and trabecular degradation, and soft tissue involvement, consistent with chronic osteomyelitis. Sphingomonas sp., a bacterium that forms biofilms, was identified as the pathogen. Among the printing methods, PolyJet and SLA demonstrated the highest anatomical accuracy, whereas FDM exhibited greater geometric deviation. Conclusions: HR-pQCT-guided 3D printing provides a powerful tool for the anatomical visualisation and quantitative assessment of complex bone pathology. This approach not only enhances diagnostic precision but also supports applications in surgical rehearsal and forensic analysis. It illustrates the potential of digital imaging and additive manufacturing to advance orthopaedic and trauma care, inspiring future research and applications in the field. Full article

Background/Objectives: Although technology has progressed and novel dosage forms have been developed, tablets are still the most used form of medication. However, the present manufacturing methods of these oral solid dosage forms offer limited capacity for personalized treatment and adaptable dosing. Personalized therapy, with a few exceptions, is not yet a part of routine clinical practice. Drug printing could be a possible approach to increase the use of personalized therapy. The aim of this work was to investigate the role of surface tension and the viscosity of inks in the formation of the printing pattern and to investigate how the porosity of substrate tablets influences the behavior of inks on the surface. Methods: Spray-dried mannitol served as a binder and filler, while magnesium stearate functioned as a lubricant in the preparation of substrate tablets. Brilliant Blue dye was a model “drug”. The ink formulation was applied to the substrates in three varying quantities. Results: Increasing the viscosity enhanced the drug content, potentially improving printing speed and pattern accuracy. However, it negatively impacted the dosing accuracy due to nozzle clogging and prolonged drying time. Viscosity had a significantly higher impact on the ink behavior than surface tension. Lowering the surface tension improved the dosing accuracy and reduced the drying time but resulted in smaller drop sizes and decreases in pattern accuracy. Reducing the substrate porosity led to longer drying times and diminished pattern accuracy. Conclusions: A target surface tension of around 30 mN/m is suggested for inkjet printing. It is necessary to further investigate the applicability of the technology with solutions of inks with high viscosity and low surface tension, including the API. Full article

Multi-layer cell constructs produced in vitro are an innovative treatment option to support the growing demand for therapy in regenerative medicine. Our research introduces a novel construct integrating organ-derived decellularised extracellular matrix (dECM) hydrogels and 3D-printed biodegradable polymer meshes composed of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) and poly(3-hydroxybutyrate-co-4-hydroxybutyrate) (P34HB) to support and maintain multiple layers of different cell types. We achieved that by integrating the mechanical stability of PHBV+P34HB, commonly used in the food storage industry, with a dECM hydrogel, which replicates organ stiffness and supports cellular survival and function. The construct was customised by adjusting the fibre arrangement and pore sizes, making it a suitable candidate for a personalised design. We showed that the polymer is degradable after precoating it with PHB depolymerase (PhaZ), with complete degradation achieved in 3–5 days and delayed by adding the hydrogel to 10 days, enabling tuneable degradation for regenerative medicine applications. Finally, as a proof of concept, we composed a three-layered tissue in vitro; each layer represented a different tissue type: epidermal, vascular, and subcutaneous layers. Possible future applications include wound healing and diabetic ulcer paths, personalised drug delivery systems, and personalised tissue implants. Full article

Three-dimensional (3D) bioprinting has emerged as a highly promising technology within the realms of tissue engineering and regenerative medicine. The assessment of printability is essential for ensuring the quality of bio-printed constructs and the functionality of the resultant tissues. Polymer materials, extensively utilized as bioink materials in extrusion-based bioprinting, have garnered significant attention from researchers due to the critical need for evaluating and optimizing their printability. Machine learning, a powerful data-driven technology, has attracted increasing attention in the evaluation and optimization of 3D bioprinting printability in recent years. This review provides an overview of the application of machine learning in the printability research of polymers for 3D bioprinting, encompassing the analysis of factors influencing printability (such as material and printing parameters), the development of predictive models, and the formulation of optimization strategies. Additionally, the review briefly explores the utilization of machine learning in predicting cell viability, evaluates the advanced nature and developmental potential of machine learning in 3D bioprinting, and examines the current challenges and future trends. Full article

Background: Automated semi-solid extrusion (SSE) material deposition is a promising new technology for preparing personalized medicines for different patient groups and veterinary applications. The technology enables the preparation of custom-made oral elastic gel tablets of active pharmaceutical ingredient (API) by using a semi-solid polymeric printing ink. Methods: An automated SSE material deposition method was used for generating chewable gel tablets loaded with propranolol hydrochloride (-HCl) at three different API content levels (3.0 mg, 4.0 mg, 5.0 mg). The physical appearance, surface morphology, dimensions, mass and mass variation, process-derived solid-state changes, mechanical properties, and in-vitro drug release of the gel tablets were studied. Results: The inclusion of API (1% w/w) in the semi-solid CuraBlend^TM printing mixture decreased viscosity and increased fluidity, thus promoting the spreading of the mixture on the printed (material deposition) bed and the printing performance of the gel tablets. The printed gel tablets were elastic, soft, jelly-like, chewable preparations. The mechanical properties of the gel tablets were dependent on the printing ink composition (i.e., with or without propranolol HCl). The maximum load for the final deformation of the CuraBlend™-API (3.0 mg) gel tablets was very uniform, ranging from 73 N to 80 N. The in-vitro dissolution test showed that more than 85% of the drug load was released within 15–20 min, thus verifying the immediate-release behavior of these drug preparations. Conclusions: Automated SSE material deposition as a modified 3D printing method is a feasible technology for preparing customized oral chewable gel tablets of propranolol HCl. Full article

Background/Objectives. Flavonoids are a vast class of phenolic substances. To date, approximately 6000 plant-origin flavonoids have been discovered, with many of them being used in drug therapy. Therapeutic flavonoids are commonly formulated to conventional “one-size-fits-all” dosage forms, such as conventional tablets or hard capsules. However, the current trends in pharmacy and medicine are centred on personalised drug therapy and drug delivery systems (DDSs). Therefore, 3D printing is an interesting technique for designing and preparing novel personalised pharmaceuticals for flavonoids. The aim of the present study was to develop aqueous polyethylene oxide (PEO) gel inks loaded with rutin for semisolid extrusion (SSE) 3D printing. Methods. Rutin (a model substance for therapeutic flavonoids), Tween 80, PEO (MW approx. 900,000), ethanol, and purified water were used in PEO gels at different proportions. The viscosity and homogeneity of the gels were determined. The rutin–PEO gels were printed with a bench-top Hyrel 3D printer into lattices and discs, and their weight and effective surface area were investigated. Results. The key SSE 3D-printing process parameters were established and verified. The results showed the compatibility of rutin as a model flavonoid and PEO as a carrier polymer. The rutin content (%) and content uniformity of the 3D-printed preparations were assayed by UV spectrophotometry and high-performance liquid chromatography (HPLC). Conclusions. The most feasible aqueous PEO gel ink formulation for SSE 3D printing contained rutin 100 mg/mL and Tween 80 50 mg/mL in a 12% aqueous PEO gel. The 3D-printed dosage forms are intended for the oral administration of flavonoids. Full article

This article describes the use of 3D printing as a tool for the design of a dosing device for intramuscular injections by nursing professionals. A device that is safer against accidental punctures, easy to use, and functional. After the analysis of the problem by a multidisciplinary team, which included nurses and engineers, a first basic prototype has been built for testing. In the process, software for solid modeling has been used; functional prototypes have been developed from the virtual models by rapid prototyping using fused deposition modeling technology (FDM), in Polylactic Acid (PLA) material, and have been tested to verify their mechanical properties and suitability for function. The project has developed a functional design that has been patented, and is in the clinical trials phase. This study demonstrates the efficacy of three-dimensional (3D) printing technologies to expedite the design process and build low-cost functional prototypes. The dosing and needle-protection mechanisms are driven by compression springs; the forces needed for both mechanisms were initially estimated through theoretical calculations and verified through empirical testing. Full article

Electrically conductive hydrogels are gaining attention owing to their applications in biosensing, cellular interfaces, and tissue engineering. However, conventional hydrogels often lack adequate electrical conductivities. Here, we present two novel conductive alginate-based hydrogels designed for extrusion-based 3D bioprinting: (i) covalently synthesized alginate–polypyrrole (alginate–PPy) via EDC/NHS-mediated conjugation with 3-aminopropyl pyrrole, and (ii) nanoparticle-reinforced alginate blended with polypyrrole nanoparticles (alginate@PPy-NP). Both systems exhibited shear-thinning behavior, tunable viscoelasticity, and excellent printability. Alginate@PPy-NP demonstrated superior compressive strength and shape fidelity, whereas alginate–PPy showed enhanced elastic moduli (G′/G″), reflecting a more uniform gel network. Electrical conductivity increased with increasing pyrrole content in both formulations. Optimization of the composition and printing conditions enabled the fabrication of fibroblast-laden constructs with high structural integrity. This work highlights the potential of alginate–polypyrrole hydrogels as customizable, conductive bioinks for 3D bioprinting in regenerative medicine. Full article

Effective bone tissue regeneration remains pivotal in implant dentistry, particularly for edentulous patients with compromised alveolar bone due to atrophy and sinus pneumatization. Biomaterials are essential for promoting regenerative processes by supporting cellular recruitment, vascularization, and osteogenesis. This study presents the development and characterization of a novel lithography-printed ceramic β-TCP scaffold, with a macro/micro-porous lattice, engineered to optimize osteoconduction and mechanical stability. Morphological, structural, and biomechanical assessments confirmed a reproducible microarchitecture with suitable porosity and load-bearing capacity. The scaffold was also employed for maxillary sinus augmentation, with postoperative evaluation using micro computed tomography, synchrotron imaging, histology, and Fourier Transform Infrared Imaging analysis, demonstrating active bone regeneration, scaffold resorption, and formation of mineralized tissue. Advanced imaging supported by deep learning tools revealed a well-organized osteocyte network and high-quality bone, underscoring the scaffold’s biocompatibility and osteoconductive efficacy. These findings support the application of these 3D-printed β-TCP scaffolds in regenerative dental medicine, facilitating tissue regeneration in complex jawbone deficiencies. Full article

The recent advancement of 3D-printed drugs is an emerging technology that has the potential for effective and safe oral delivery of personalized treatment regimens to patients, replacing the current “one size fits all” philosophy. The objective of this literature review is to highlight the importance of 3D-printing technology in the development of personalized treatments, focusing on Levetiracetam, the first FDA-approved 3D-printed drug, for the treatment of epilepsy. Levetiracetam serves as an ideal paradigm for exploring how precision medicine and 3D printing can be applied to improve treatment outcomes for other complex diseases such as diabetes, cardiovascular diseases, and cancer. 3D printing enables precise dosage and time-release profiles by modifying factors such as shape and size, and the combination of active pharmaceutical ingredients (APIs) and excipients, ensuring consistent therapeutic levels over the treatment period. Design of oral tablets with multiple compartments allows for simultaneous treatment with multiple APIs, each one with a different release profile, minimizing drug–drug interactions and side effects. This technology also supports on-demand production, making it particularly beneficial in resource-limited or urgent situations, and offers the flexibility to customize dosage forms. Additive manufacturing could be an important tool for developing personalized treatments to address the diverse medical needs of patients with complex diseases. Therefore, there is a need for more 3D-printed FDA-approved drugs in the biopharmaceutical industry to enable personalized treatment, improved patient compliance, and precise drug release control. Full article

Spinal cord injuries (SCIs) present a major clinical challenge, often resulting in permanent loss of function and limited treatment options. Traditional approaches, including surgery, drugs, and rehabilitation, have had modest success in restoring neural connectivity due to the complex pathophysiology of SCI. In recent years, bioactive hydrogels have gained attention as a versatile platform for neural repair. Their ability to mimic the extracellular matrix, deliver therapeutic agents, and support cell survival makes them promising tools in regenerative medicine. This narrative review highlights the latest advances in hydrogel-based therapies for SCI, with a focus on innovations such as self-healing, conductive, and anti-inflammatory hydrogels. We also explore hybrid approaches that integrate nanomaterials, stem cells, and bioelectronics to address both primary and secondary injury mechanisms. While various hydrogel systems have been investigated, we place particular emphasis on gelatin-based hydrogels, especially gelatin methacryloyl (GelMA), due to their emerging clinical relevance. GelMA stands out for its bioactivity, tunable mechanics, and compatibility with 3D printing, making it a strong candidate for personalized therapies and scalable production. Unlike previous reviews that broadly summarize hydrogel use, this work specifically contextualizes gelatin-based platforms within the wider landscape of SCI repair, underscoring their translational potential. We also address current challenges, such as immune response, long-term integration, and clinical validation, and suggest future directions for bridging the gap from bench to bedside. Full article

In the last years, considerable innovation has been made regarding bioprinting, particularly in the development of cell-loaded hydrogels. The specific properties of the bioinks are crucial for printing an adequate cell-laden hydrogel structure. In this research, we aimed to develop a 3D-printable hydrogel using a natural biocompatible polymer. The process is based on the use of sodium alginate subjected to calcium ion cross-linking for immediate stiffness after printing. Using the Cellink INKREDIBLE+ printer (Cellink Inc., Goteborg, Sweden), 3D structures were successfully produced. The developed bioink exhibited a viscosity suitable for extrusion printing while ensuring its structural integrity at the same time. Next, 3D spheroids developed by using bioinks were morphologically characterized by using light, a fluorescent microscope, and field emission scanning electron microscopy (FESEM). In conclusion, the properties of the construct obtained using the lab-formulated biocompatible polymer hydrogel suggest its potential use as a framework for three-dimensional cell culture, with possible applications in both fields of research and regenerative medicine. Full article