Search Results (462)

Hydrogels are hydrophilic, soft polymer networks with high water content and mechanical properties that are tunable; they are also biocompatible. Therefore, as biomaterials, they are of interest to modern medicine. In this review, the main applications of hydrogels in essential clinical applications are discussed. Chemical, physical, or hybrid crosslinking of either synthetic or natural polymers allow for the precise control of hydrogels’ physicochemical properties and their specific characteristics for certain applications, such as stimuli-responsiveness, drug retention and release, and biodegradability. Hydrogels are employed in gynecology to regenerate the endometrium, treat infections, and prevent pregnancy. They show promise in cardiology in myocardial infarction therapy through injectable scaffolds, patches in the heart, and medication delivery. In rheumatoid arthritis, hydrogels act as drug delivery systems, lubricants, scaffolds, and immunomodulators, ensuring effective local treatment. They are being developed, among other applications, as antimicrobial coatings for stents and radiotherapy barriers for urology. Ophthalmology benefits from the use of hydrogels in contact lenses, corneal bandages, and vitreous implants. They are used as materials for chemoembolization, tumor models, and drug delivery devices in cancer therapy, with wafers of Gliadel presently used in clinics. Applications in abdominal surgery include hydrogel-coated meshes for hernia repair or Janus-type hydrogels to prevent adhesions and aid tissue repair. Results from clinical and preclinical studies illustrate hydrogels’ diversity, though problems remain with mechanical stability, long-term safety, and mass production. Hydrogels are, in general, next-generation biomaterials for regenerative medicine, individualized treatment, and new treatment protocols. Full article

The enhancement effect and mechanism of porous frameworks on hydrogel thermal control performance are key factors in evaluating their engineering applications and performance improvements. This study investigates the enhancement mechanism of porous framework composite phase-change materials (CPCM) on hydrogel thermal control performance through multi-scale visualization comparison experiments. Results indicate that pure hydrogels, due to their dense internal structure, hinder water vapor escape, thereby impeding overall fluidity and mass transfer rates. The introduction of a porous framework significantly improves internal heat transfer and moisture transport pathways within the hydrogel, enabling smooth water vapor release during heating and preventing localized heat accumulation. Under 100 °C heating conditions, CPCM exhibited a 65% reduction in mass-specific dehydration rate compared to pure hydrogel, with a 25% lower temperature drop. Energy efficiency increased by 13.5% over hydrogel, while the coefficient of variation decreased by 34.1%, demonstrating superior thermal stability and temperature control capabilities. This study elucidates from a mechanistic perspective how porous frameworks regulate the thermal and mass transfer behaviors of hydrogels, providing a theoretical basis and experimental support for their advanced application and optimization in the thermal control systems of electronic devices. Full article

Research into oral mucosa-targeted drug delivery systems (DDS) is rapidly evolving, with growing emphasis on enhancing bioavailability and precision targeting while overcoming the unique anatomical and physiological barriers of the oral environment. Despite considerable progress, challenges such as enzymatic degradation, limited mucosal penetration, and solubility issues continue to hinder therapeutic success. Recent advancements have focused on innovative formulation strategies—including nanoparticulate and biomimetic systems—to improve delivery efficiency and systemic absorption. Simultaneously, smart and stimuli-responsive materials are emerging, offering dynamic, environment-sensitive drug release profiles. One particularly promising area involves the application of glycosaminoglycans, a class of naturally derived polysaccharides with excellent biocompatibility, mucoadhesive properties, and hydrogel-forming capacity. These materials not only enhance drug residence time at the mucosal site but also enable controlled release kinetics, thereby improving therapeutic outcomes. However, critical research gaps remain: standardized, clinically meaningful mucoadhesion/permeation assays and robust in vitro–in vivo correlations are still lacking; long-term stability, batch consistency of GAGs, and clear regulatory classification (drug, device, or combination) continue to impede scale-up and translation. Patient-centric performance—palatability, mouthfeel, discreet wearability—and head-to-head trials versus standard care also require systematic evaluation to guide adoption. Overall, converging advances in GAG-based films, hydrogels, and nanoengineered carriers position oral mucosal delivery as a realistic near-term option for precision local and selected systemic therapies—provided the field resolves standardization, stability, regulatory, and usability hurdles. Full article

Background/Objectives: Inhalable Microparticles (IMPs) are part of a currently invading field of medicine. In fact, the anatomical district of Rhinopharynx represents a bed for many different pathologies and infections, where the dimension of drug aerosol Microparticles (MPs) represents a discriminating factor to success therapy. The aims of the present work are to demonstrate the efficacy of a new device and its aerosol reproducibility in the nebulization of suspensions to be deposited in the retropharynx. Materials and Methods: The Low-Angle Laser Light Scattering (LALLS) method was used to evaluate both the dimension and distribution of MPs. Six different APIs, used usually in Rhinopharynx pathology, were compared in order to investigate the dimension of MP emissions using four different devices. The results of a retrospective study including 74 subjects treated with standard therapy (ST) and the inhalation of nebulized Sobrerol (NS) were performed. Data regarding the persistence of clinical symptoms (i.e., cough and nasal constipation) were acquired. Results: No significant statistical differences among all the products tested (p > 0.05) were found. One device, Rinubes, demonstrated efficacy and robustness in the fine nebulization of all the pharmaceutical products analyzed. Rinubes delivered an aerosol cloud with significantly lower MMD (66.3 µm) than Mad Nasal and Spray-sol (142.1 and 116.0 µm, respectively), which would allow a higher fraction of drugs to be deposited in the retropharynx. The retrospective clinical study revealed that NS treatment showed higher odds of cough resolution (OR 9.18; p < 0.001) with respect to control ST and showed higher odds of nasal symptom resolution (OR 6.7; p = 0.043). Conclusions: Improved techniques for the administration of inhalable MPs (INPAD) represent significant progress in overcoming the biological and the anatomical barriers in controlling drug release at a specific site. The challenges of nasopharyngeal pathologies offer promising opportunities for the development of non-invasive drug delivery. Full article

Background/Objectives: We report the development of a novel intraocular sustained-release implantable pharmaceutical formulation, designed to be placed in the anterior chamber of the eye after cataract surgery. The device is intended to reduce postoperative inflammation, and to prevent opportunistic bacterial infections that may lead to endophthalmitis. Methods: The implants were produced via hot-melt extrusion, using a twin-screw extruder to process a homogeneous mixture of polylactide-co-glycolic acid, moxifloxacin hydrochloride (MOX HCl) and dexamethasone (DEX). Quality control tests included drug content determination, release rate profile evaluation, and several instrumental characterization techniques (scanning electron microscopy (SEM), confocal Raman microscopy, differential scanning calorimetry, and X-ray diffraction). Long-term and accelerated stability tests were also performed, following ICH guidelines. Sterilization was achieved by exposing samples to gamma radiation. In vivo exploratory studies were carried out in healthy rabbits to evaluate the safety and overall performance of the implantable formulation. Results: In terms of quality control, drug content was found to be homogeneously distributed throughout the implants, and it also met the label claim. In vitro release rate was constant for MOX HCl, but non-linear for DEX, increasing over time. In vivo preliminary tests showed that the inserts completely biodegraded within approximately 20 days. No clinical signs of anterior segment toxic syndrome or statistically significant intraocular pressure differences were found between treatment and control groups. Conclusions: The implants developed in this study can act as sustained-release depots for the delivery of both DEX and MOX HCl, and are biocompatible with ocular structures. Full article

Mg alloys hold promise for biodegradable gastrointestinal implants, but most evaluations rely on simplified media like Hank’s solution, which lacks organic components and fails to replicate the acidic-to-alkaline transition of intestinal fluid, risking underestimation of biodegradation rates and clinical relevance. This work investigated a trace-Cu-modified Mg alloy (Mg-0.05Cu) in simulated intestinal fluid (SIF) versus Hank’s solution. Microstructural analysis confirmed Mg₂Cu intermetallic phases as Cu reservoirs. Electrochemical and immersion tests revealed significantly accelerated biodegradation in SIF, due to its disruption of protective layer formation, sustaining loose biodegradation products. The biodegradation rate of the trace-Cu-modified Mg alloy in SIF was consistent with reported values for Mg alloys in similar media, as was that in Hank’s solution. Remarkably, Mg-0.05Cu exhibited potent antibacterial activity against E. coli, achieving 99.3% eradication within 12 h and 100% elimination by 24–48 h, alongside excellent cytocompatibility with L929 cells (>95% viability). This efficacy arose from the synergistic Cu²⁺ release and high-pH microenvironment. These findings demonstrate that trace Cu alloying in high-purity Mg balances rapid antibacterial action with controlled biodegradation in a physiologically relevant SIF. This positions Mg-0.05Cu as a highly promising candidate for practical applications, such as biodegradable intestinal stents, anti-adhesion barriers, anastomosis rings, and anti-obesity devices, where rapid infection control and predictable degradation are critical for clinical success. This work underscores the importance of using biomimetic media for evaluating gastrointestinal implants and establishes Mg-0.05Cu as a promising strategy for developing infection-resistant biodegradable devices. Full article

This study compared the effectiveness of gallium nitride (GaN) with a single carbon-doped (C-doped) buffer layer and a composite carbon/iron-doped (C/Fe-doped) buffer layer within an AlGaN/GaN high-electron-mobility transistor (HEMT). In traditional power devices, Fe-doping has a large memory effect, causing Fe ions to diffuse outwards, which is undesirable in high-power-device applications. In the present study, a C-doped GaN layer was added above the Fe-doped GaN layer to form a composite buffer against Fe ion diffusion. Direct current (DC) characteristics, pulse measurement, low-frequency noise, and variable temperature analysis were performed on both devices. The single C-doped buffer layer in the AlGaN/GaN HEMT had fewer defects in capturing and releasing carriers, and better dynamic characteristics, whereas the composite C/Fe-doped buffers, by suppressing Fe migration toward the channel, showed higher vertical breakdown voltage and lower sheet resistance, and still demonstrated potential for further performance tuning to achieve enhanced semi-insulating behavior. With optimized doping concentrations and layer thicknesses, the dual-layer configuration offers a promising path toward improved trade-offs between leakage suppression, trap control, and dynamic performance for next-generation GaN-based power devices. Full article

Background/Objectives: Chronic retinal diseases usually require repetitive local dosing. Depending on factors such as dosing frequency, mode of administration, and associated costs, this can result in poor patient compliance. A better alternative involves using controlled-release drug delivery systems to reduce the frequency of intravitreal dosing and extend drug release. However, reaching the market stage is a time-consuming process. Methods: In this study, we employed two computational approaches to model and estimate the parameters governing the diffusion-controlled drug release from bi-layered microspheres. The case study involved microspheres composed of a chitosan core and a polycaprolactone (PCL) shell. The model drugs were bovine serum albumin and bevacizumab (an agent that slows neovascularization due to retinal disorders). Drug release from the microspheres is described by a mathematical model that was solved numerically using the finite difference and the finite element approaches. The parameter estimation was performed by nonlinear least-squares regression. Results: We used the estimated parameters to simulate the cumulative release under various conditions and optimize the device design to guide future experimental efforts and improve the duration of release beyond a target daily therapeutic release rate from the microspheres. Conclusions: We investigated the effects of polymeric layer sizes on drug release and provided recommendations for optimal sizes. We provide straightforward computational tools for others to reuse in designing bi-layered microspheres for intravitreal drug delivery needs in the treatment of chronic ocular neovascularization. Full article

A natural deep eutectic solvent (NADES)-based electropolymerization strategy was developed to deposit polypyrrole (PPy) and Naproxen-doped PPy films onto a biomedical Ti–20Zr–5Ta–2Ag high-entropy alloy. Using cyclic voltammetry, chronoamperometry, and chronopotentiometry, coatings were grown potentiostatically (1.2–1.6 V) or galvanostatically (0.5–1 mA) to fixed charge values (1.6–2.2 C). Surface morphology and composition were assessed by optical microscopy, SEM and FTIR, while wettability was quantified via static contact-angle measurements in simulated body fluid (SBF). Electrochemical performance in SBF was evaluated through open-circuit potential monitoring, potentiodynamic polarization, and electrochemical impedance spectroscopy. Drug-release kinetics were determined by UV–Vis spectrophotometry and analyzed using mathematical modelling. Compared to uncoated alloy, PPy and PPy–Naproxen coatings increased hydrophilicity (contact angles reduced from ~31° to <10°), and reduced corrosion current densities from 754 µA/cm² to below 5.5 µA/cm², with polarization resistances rising from 0.06 to up to 37.8 kΩ·cm². Naproxen incorporation further enhanced barrier integrity (R_coat up to 1.4 × 10¹¹ Ω·cm²) and enabled sustained drug release (>90% over 8 days), with diffusion exponents indicating Fickian (n ≈ 0.51) and anomalous (n ≈ 0.67) transport for potentiostatic and galvanostatic coatings, respectively. These multifunctional PPy–Naproxen films combine robust corrosion protection with controlled therapeutic delivery, supporting their potential biomimetic role as smart coatings for next-generation implantable devices. Full article

Endotoxins, lipopolysaccharides released from the outer membrane of Gram-negative bacteria, pose a significant risk in healthcare environments, particularly in Central Sterile Supply Departments (CSSDs), where the delivery of sterile pyrogen-free medical devices is critical for patient safety. Traditional methods for controlling endotoxins in water systems, such as ultraviolet (UV) disinfection, have proven ineffective at reducing endotoxin concentrations to comply with regulatory standards (<0.25 EU/mL). This limitation presents a significant challenge, especially in the context of reverse osmosis (RO) permeate used in CSSDs, where water typically has very low conductivity. Despite the established importance of endotoxin removal, a gap in the literature exists regarding effective chemical-free methods that can meet the stringent endotoxin limits in such low-conductivity environments. This study addresses this gap by evaluating the effectiveness of the eBooster™ electrochemical technology—featuring proprietary electrode materials and a reactor design optimized for potable water—for endotoxin removal from water, specifically under the low-conductivity conditions typical of RO permeate. Laboratory experiments using the B250 reactor achieved >90% endotoxin reduction (from 1.2 EU/mL to <0.1 EU/mL) at flow rates ≤5 L/min and current densities of 0.45–2.7 mA/cm². Additional real-world testing at three hospitals showed that the eBooster™ unit, when installed in the RO tank recirculation loop, consistently reduced endotoxin levels from 0.76 EU/mL (with UV) to <0.05 EU/mL over 24 months of operation, while heterotrophic plate counts dropped from 190 to <1 CFU/100 mL. Statistical analysis confirmed the reproducibility and flow-rate dependence of the removal efficiency. Limitations observed included reduced efficacy at higher flow rates, the need for sufficient residence time, and a temporary performance decline after two years due to a power fault, which was promptly corrected. Compared to earlier approaches, eBooster™ demonstrated superior performance in low-conductivity environments without added chemicals or significant maintenance. These findings highlight the strength and novelty of eBooster™ as a reliable, chemical-free, and maintenance-friendly alternative to traditional UV disinfection systems, offering a promising solution for critical water treatment applications in healthcare environments. Full article

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

Polymeric composite thin films have emerged as promising antimicrobial materials, particularly in response to rising antibiotic resistance. This review highlights the development and application of such films produced by laser-based deposition techniques, notably pulsed laser deposition and matrix-assisted pulsed laser evaporation. These methods offer precise control over film composition, structure, and thickness, making them ideal for embedding antimicrobial agents such as metal nanoparticles, antibiotics, and natural compounds into polymeric matrices. The resulting composite coatings exhibit enhanced antimicrobial properties against a wide range of pathogens, including antibiotic-resistant strains, by leveraging mechanisms such as ion release, reactive oxygen species generation, and membrane disruption. The review also discusses critical parameters influencing antimicrobial efficacy, including film morphology, composition, and substrate interactions. Applications include biomedical devices, implants, wound dressings, and surfaces in the healthcare and food industries. Full article

We present a buffer-pH-modulated electrokinetic concentration strategy in MEMS microchannels that harnesses simple pH shifts to neutralize and charge proteins, reversibly “pausing” them at a planar electric-gate electrode by tuning to their isoelectric point (pI) and mobilizing them with slight pH offsets under an applied field. This synergistic coupling of dynamic pH control and electrode-gated focusing, which requires only buffer composition changes, enables rapid and tunable protein capture and release across diverse channel geometries for lab-on-chip, preparative, and point-of-care diagnostics. Moreover, it dovetails with established MEMS biomedical platforms ranging from diagnostics to drug delivery and microsurgery to gene and cell-manipulation devices. Future work on tailored electrode coatings and optimized channel profiles will further boost selectivity, speed, and integration in sub-100 µm MEMS devices. Full article

Phase change materials (PCMs) have significant potential for utilization due to their high energy storage density and excellent safety in energy storage. In this research, a flexible heat storage device using the stable supercooling of sodium acetate trihydrate composite is developed, enabling on-demand heat release through controlled solidification initiation. The solidification and heat release characteristics are investigated in experiments. The results indicate that the heat release characteristics of this heat storage device are closely linked to the crystallization process of the PCM. During the experiment, based on whether external intervention was needed for the solidification process, the PCM manifested two separate solidification modes—specifically, spontaneous self-solidification and triggered-solidification. Meanwhile, the heat release rates, temperature changes, and crystal morphologies were observed in the two solidification modes. Compared with spontaneous self-solidification, triggered-solidification achieved a higher peak surface temperature (53.6 °C vs. 46.2 °C) and reached 45 °C significantly faster (5 min vs. 15 min). Spontaneous self-solidification exhibited slower, uncontrollable heat release with dendritic crystals, while triggered-solidification provided rapid, controllable heat release with dense filamentous crystals. This controllable switching between modes offers key practical advantages, allowing the device to provide either rapid, high-power heat discharge or slower, sustained release as required by the application. According to the crystal solidification theory, the different supercooling degrees are the main reasons for the two solidification modes exhibiting different solidification characteristics. During solidification, the growth rate of SAT crystals exhibits substantial disparities across diverse experiments. In this research, the maximum axial growth rate is 2564 μm/s, and the maximum radial growth rate is 167 μm/s. Full article

Background/Objectives: Personalized 3D-printed (3DP) metallic implants delivery systems are being explored to repair bone fractures, allowing the customization of medical implants that respond to individual patient needs, making it potentially more effective and of greater quality than mass-produced devices. However, challenges associated with postsurgical infections caused by bacterial adhesion remain a clinical issue. To address this, local antibiotic therapies are receiving extensive attention to minimize the risk of implant-related infections. This study investigated the use of amikacin (AMK), a broad-spectrum aminoglycoside antibiotic, incorporated onto 3D-printed 316L stainless steel implants using biodegradable polymer coatings of chitosan and poly lactic-co-glycolic acid (PLGA). Methods: This research examined different approaches to coat 3DP implants with amikacin. Various polymer-based coatings were studied to determine the optimal formulation based on the characteristics and release profile. The optimal formulation was performed on the antibacterial activity studies. Results: AMK-chitosan with PLGA coating implants controlled the rate of drug release for up to one month. The 3DP drug-loaded substrates demonstrated effective, concentration-dependent antibacterial activity against common infective pathogens. AMK-loaded substrates showed antimicrobial effectiveness for one week and inhibited bacteria significantly compared to the uncoated controls. Conclusions: This study demonstrated that 3DP metal surfaces coated with amikacin can provide customizable drug release profiles while effectively inhibiting bacterial growth. These findings highlight the potential of combining 3D printing with localized delivery strategies to prevent implant-associated infections and advance the development of personalized therapies. Full article