Biomedical Materials

Compared with traditional soft tissue wound closure methods such as sutures and staplers, bioadhesives have significant advantages in terms of tissue compatibility, ease of use, and wound adaptability, making them a hot topic among current wound repair materials. This study aimed to select polyurethane materials with good biocompatibility and high mechanical strength, optimize the prepolymer formula, develop new curing agents, and obtain a new dual-component polyurethane bioadhesive. Furthermore, key research will be conducted on its mechanical properties and tissue adhesion performance. The results show that through the optimization of prepolymer formulations and the development of novel curing agents, a dual-component polyurethane bioadhesive with good biocompatibility, flexibility, and high adhesive strength was obtained. This adhesive can quickly and effectively bond common soft tissue (skin, muscle) traumatic wounds, with an adhesive strength of up to 72 kPa. This adhesive matches well with the mechanical properties of soft tissues and safely and tightly adheres to the surface of soft tissues. Additionally, this dual-component polyurethane adhesive holds promise for repairing other soft tissues, such as the lungs and intestines, with broad application prospects.

Osteoarthritis (OA) has become a common degenerative joint disease, lacking clinical means to alleviate this disease. Melittin, taken from natural honeybee venom, possesses outstanding anti-inflammatory properties and has great potential to treat OA. However, its high toxicity and hemolytic properties limit its application. In this work, a biocompatible hydrogel was prepared from extracellular matrix (ECM) of rib cartilage, possessing fibrous mesh structure characteristics, which was beneficial for melittin loading. It was found that the use of ECM hydrogel loaded with melittin can reduce the intrinsic toxicity of melittin and prolong the release behavior, simultaneously. The in vitro study demonstrated that melittin-hydrogel could effectively inhibit phosphorylation-ERK/JNK, prevent the exacerbation of TNF-α-induced apoptosis in ATDC5 cells, and reduce their inflammatory markers, effectively alleviating OA and preventing cartilage degradation. Subsequently, in vivo studies have demonstrated that injecting melittin-hydrogel into the joint cavity of OA mice can effectively reduce cartilage degeneration. These findings suggest that melittin-hydrogel plays a critical role in the development of OA and may provide a therapeutic option for the treatment of OA disease.

Nanoparticle-mediated drug delivery has revolutionized nano-therapeutics. It ensures improved biodistribution, longer blood circulation, and improved bioavailability inside the body. The loading efficiency and stability of the drug within the carrier are the major challenges for ideal drug delivery. In this study, we have synthesized indocyanine green (ICG) loaded Poly-L-Lysine (PLL) nanoparticles by a two-step self-assembly process using a green chemistry approach, where water-based solvents were used for fabrication such as phosphate-buffered saline (PBS, pH 7.4), deionized water (DI), and Milli-Q water (MQ). The effect of these solvents on the morphology, stability and loading efficiency of ICG was investigated using UV-visible spectroscopy, fluorescence spectroscopy, scanning electron microscopy, and dynamic light scattering. The results demonstrated that nanoparticles can be fabricated using all the three solvents, however, there was a huge difference between their functional and morphological properties. These functional and morphological properties play important role in their biomedical applications. It was found that PBS-based NPs showed the maximum loading of ICG followed by DI water and MQ water respectively. The PBS suspended ICG-loaded PLL nanoparticles were highly monodispersed with the mean diameter of ∼200 nm and showed highest photothermal efficiency. The green synthesized biocompatible and biodegradable NPs were designed to treat solid tumors via local hyperthermia due to photothermal property of these NPs. The photothermal cytotoxicity assessment of PBS-based PLL-ICG NPs in both 2D and 3D in vitro cultures displayed notable efficacy. Therefore, we conclusively demonstrate that selection of right solvent is crucial to realize the full potential of green-synthesized polymeric nanoparticles.

Anterior foregut endoderms (AFEs) derived from induced pluripotent stem cells (iPSCs) are an important cell source in stem cell technology as they give rise to some important lineages like lung progenitors and thyroid cells. Coating substrates plays a critical role in AFE generation. Currently, conventional large molecule proteins like Matrigel are used in most differentiation protocols. However, the complex components and mechanisms of these coatings have limited both the exploration of cell–extracellular matrix (ECM) interaction and potential clinical applications. In this study, we identified eight pure synthetic integrin-binding short peptides as effective coatings for iPSC growth and AFE generation with an integrin-binding peptide array. Our results showed that integrin α5β1-, αVβ8-, and αIIbβ3-binding peptides supported the adhesion and expansion of iPSCs and AFE generation by guided differentiation via a definitive endoderm (DE) in a full-anchorage-dependent manner. AFE generation was also found on coatings based on integrin α3β1-, α6β1-, αVβ1-, αVβ6-, and αMβ2-binding peptides following a process with temporal suspension growth in the DE-inducing stage, with lower AFE generation efficiency compared to the full-anchorage-dependent peptide groups and Matrigel. According to the results, the integrin α5β1-binding peptide is the most promising defined substrate for inducing AFEs because of its equivalent efficiency with traditional Matrigel coating in supporting iPSC expansion and differentiation toward AFEs. Additionally, the other seven peptide-based coatings also exhibit potential and could be further investigated for developing synthetic-coating strategies in future studies involving AFEs. Our findings provide valuable insights into the role of integrin and ECM function and hold great potential for disease modeling as well as therapeutic exploration of AFE origin organs.

The erosion and drug release behavior of an injectable hydrogel composed of ethoxylated trimethylolpropane tri-3-mercaptopropionate (ETTMP) and poly(ethylene glycol) diacrylate were determined under physiological conditions. Water and polymer mass changes were monitored over time to characterize the swelling/deswelling and erosion of the hydrogel tablets. Experimental data were collected for hydrogels with varying polymer fractions. These data were used to develop an empirical model to predict the eroding mass change and equilibrium water content across different compositions. Three easily detectable model drugs (methylene blue (MB), sulforhodamine 101, and chloroquine) were loaded into 25, 35, and 50 wt% polymer hydrogels to understand their drug release behavior. The gelation time and time for total drug release were dependent on the weight fraction of the polymer in the hydrogel and varied with the pH of the drug solutions, with more acidic drugs increasing gelation time. Complete drug release was not observed for MB because of the reaction with ETTMP thiol groups, demonstrating the importance of understanding the potential interactions between the drug and polymer. Drug-loaded hydrogels were also monitored for erosion and were found to swell more than their neat counterparts for all drugs tested, suggesting an effect of drug loading on the extent of hydrogel crosslinking.

Bone injury presents a prevalent challenge in clinical settings, with traditional treatment modalities exhibiting inherent limitations. Recent advancements have highlighted the potential of combining physical exercise intervention and innovative materials to enhance bone repair and recovery. This review explores the synergistic effects of physical exercise and novel materials in promoting bone regeneration, with a particular focus on the role of neurovascular coupling (NVC) mechanisms. Physical exercise not only stimulates bone cell function and blood circulation but also enhances the bioactivity of novel materials, such as nanofiber membranes and smart materials, which provide supportive scaffolds for bone cell attachment, proliferation, and differentiation. NVC, involving the interaction between neural activity and blood flow, is integral to the bone repair process, ensuring the supply of nutrients and oxygen to the injured site. Studies demonstrate that the combination of physical exercise and novel materials can accelerate bone tissue regeneration, with exercise potentially enhancing the bioactivity of materials and materials improving the effectiveness of exercise. However, challenges remain in clinical applications, including patient variability, material biocompatibility, and long-term stability. Optimizing the integration of physical exercise and novel materials for optimal therapeutic outcomes is a key focus for future research. This review examines the collaborative mechanisms between physical exercise, novel materials, and NVC, emphasizing their potential and the ongoing challenges in clinical settings. Further exploration is needed to refine their application and improve bone repair strategies.

Intervention without implantation has become a requirement for developing percutaneous coronary intervention for coronary heart disease. In this paper, the recent advances of three representative types of bioresorbable metal coronary drug-eluting stents (DESs) are reviewed, and the material composition, structural design, mechanical properties and degradability of iron-based, magnesium-based and zinc-based bioresorbable metal coronary DES are analyzed. The methods of regulating the radial strength and degradation rate of the coronary stents are summarized, and the in vivo/in vitro performance evaluation methods and ideal testing systems of the bioresorbable metal coronary DES are analyzed. Advances made in bioresorbable metal coronary DES, the existing shortcomings and optimization methods are proposed, and the future development direction is prospected.

Temporary anchorage devices (TADs) have evolved as useful anchorage providers for orthodontic tooth movements. To improve the stability of TADs, a number of modifications on their surface have been developed and investigated. This review comprehensively summarizes recent findings of clinically applied surface modifications of TADs and compared the biological improvement of these modifications. We focused on sandblasting, large-grit, acid etching (SLA), anodic oxidation (AO) and ultraviolet photofunctionalization (UVP). In vitro, in vivo and clinical studies of these surface modifications on TADs with clear explanations, low possibility of bias and published in English were included. Studies demonstrated that SLA, AO and UVP enhance cell attachment, proliferation, and differentiation in vitro. The biocompatibility and osteoconductivity of TAD surface are improved in vivo. However, in clinical studies, the changes are generally not so impressive. Furthermore, this review highlights the promising potential in combinations of different modifications. In addition, some other surface modifications, for instance, the biomimetic calcium phosphate coating, deserve to be proposed as future strategies.

Bioprinting, an advanced additive manufacturing technology, enables the fabrication of complex, viable three-dimensional (3D) tissues using bioinks composed of biomaterials and cells. This technology has transformative applications in regenerative medicine, drug screening, disease modeling, and biohybrid robotics. In particular, in situ bioprinting has emerged as a promising approach for directly repairing damaged tissues or organs at the defect site. Unlike traditional 3D bioprinting, which is confined to flat surfaces and require complex equipment, in situ techniques accommodate irregular geometries, dynamic environments and simple apparatus, offering greater versatility for clinical applications. In situ bioprinting via hand-held devices prioritize flexibility, portability, and real-time adaptability while allowing clinicians to directly deposit bioinks in anatomically complex areas, making them cost-effective, accessible, and suitable for diverse environments, including field surgeries. This review explores the principles, advancements, and comparative advantages of robotic and hand-held in situ bioprinting, emphasizing their clinical relevance. While robotic systems excel in precision and scalability, hand-held bioprinters offer unparalleled flexibility, affordability, and ease of use, making them a valuable tool for personalized and minimally invasive tissue engineering. Future research should focus on improving biosafety, aseptic properties, and bioink formulations to optimize these technologies for widespread clinical adoption.

Natural polymer-based hydrogels, generally composed of hydrophilic polymers capable of absorbing large amounts of water, have garnered attention for biomedical applications because of their biocompatibility, biodegradability, and eco-friendliness. Natural polymer-based hydrogels derived from alginate, starch, cellulose, and chitosan are particularly valuable in fields such as drug delivery, wound dressing, and tissue engineering. However, compared with synthetic hydrogels, their poor mechanical properties limit their use in load-bearing applications. This review explores recent advancements in the enhancement of the mechanical strength of natural hydrogels while maintaining their biocompatibility for biomedical applications. Strategies such as chemical modification, blending with stronger materials, and optimized cross-linking are discussed. By improving their mechanical resilience, natural hydrogels can become more suitable for demanding biomedical applications, like tissue scaffolding and cartilage repair. Additionally, this review identifies the ongoing challenges and future directions for maximizing the potential of natural polymer-based hydrogels in advanced medical therapies.

Critical bone defects require repair materials for optimal treatment. The current range of available materials has limitations, including donor availability, rejection, disease transmission, and inadequate filling. Calcium phosphate bone cement (CPC) is a bone repair material, but most CPCs on the mar-ket have two drawbacks: difficulty degrading and prolonged solidification time. The purpose of this study was to develop a CPC that is rapidly moldable and biodegradable, improves the acid‒base mi-croenvironment, and is more suitable for clinical use. This CPC was prepared from β-tricalcium phosphate bioceramics (TCP) and calcium phosphate monohydrate and is designated a bioceramic calcium phosphate bone cement (BCPC). TCP was used as a control to determine the biocompatibil-ity of BCPC and its impact on osteogenesis-related protein activity. The BCPC and TCP implants were placed in the femurs of rabbits, and X-ray/micro-CT images were obtained at weeks 4, 8, and 12 postoperatively. Additionally, samples from the three time points were stained and analyzed for their osteogenic and degradation properties. BCPC submerged in phosphate buffer reached a neutral pH of 6.98 ± 0.02 on Day 3. In vitro tests revealed that BCPC increased alkaline phosphatase and osteo-pontin activities in MC3T3-E1 cells. The X-ray and micro-CT results revealed that BCPC degraded while the TCP volume remained stable. Micro-CT revealed that BCPC degraded by 26.93% and formed 12.89% new bone by week 12. The histological results showed that BCPC had good bio-compatibility and osteointegration ability. BCPC is characterized by rapid solidification and molding and good biocompatibility, and its degradation rate matches the rate of bone regeneration. BCPC could rapidly improve the surrounding pH, providing the foundation for its clinical application.

In this study the first-time introduction of Kollidon® 25 (K25) thermoplastic polymer, which was not earlier explored in PBF-based 3D printing technology along with the simultaneous usage of Kollidon® SR (KSR) to form a thermoplastic polymer composite for the development of tunable solid oral dosage form (SODFs). In addition to this, a novel laser-absorbing dye i.e., Pigment Green 7 (PG-7) was also introduced to facilitate the laser sintering process of the used thermoplastic polymer composites. Sintered tablets obtained from the used thermoplastic polymer bed composites were systematically characterized using various analytical tools and in vitro examinations as well. The physicochemical characterization of all sintered tablet batches (B1-B7) was within the acceptable limit. Thermal and chemical analyses revealed no detrimental physical or chemical interactions between the components, as well as after exposure of sintered tablet batches to laser and temperature. Powder X-ray diffraction diffractograms suggested a change in the native state of tinidazole (TNZ, used as an active pharmaceutical ingredient) to amorphous due to the exposure of sintering parameters. Scanning electron microscopy micrographs of all batches showed intense fusion of the particles in the polymer composite. The sintered tablet batches B1 to B7 exhibited a drug content ranging from 90.36 ± 4.32% to 99.36 ± 1.24%. TNZ released in an acidic medium for up to 2.0 h from different sintered tablets were around 100% to 12% from B1 to B7 batches, respectively following alkaline medium for up to 12.0 h. TNZ release pattern was fine tuned in accordance with the changes in the composition ratio of Kollidon® 25 and Kollidon® SR polymers in order to get quick release to sustained release. This prepared unique thermoplastic pharmaceutical grade polymer composite might broaden the range of materials accessible for PBF-mediated 3D printing in pharmaceutical industrial applications in near future.

Despite their impact on cancer therapy, limitations such as systemic toxicity and drug resistance are encountered with platinum-based drugs. This study explores the potential of combining PtIV-based NP with Carmofur (Car) to address these issues. In this study, platinum nanoparticles (PtNP) and Car-loaded PtNP (Car@PtNP) were synthesized and their cytotoxic and apoptotic effects on colorectal and breast cancer cells were evaluated. Following characterization of the synthesized NPs by DLS, UV-VIS spectroscopy, FTIR, and STEM, it was found that the average size of PtNPs was 55.42 nm and the size increased to approximately 186.06 nm upon synthesis of Car@PtNP. MTT assays demonstrated that Car@PtNP exhibited higher levels of cellular toxicity than carmofur alone. While it significantly decreased cell viability in both colon and breast cancer cells, its toxicity to HUVEC cells was minimal. Treatment of MCF-7 and HCT116 cells with 50 µg/mL of free Car resulted in cell viabilities of 65.2% and 76.93%, respectively, whereas the viability of cells treated with Car@PtNP decreased to 49.60% and 55.47%. Flow cytometric analysis confirmed that apoptosis was increased in healthy HCT116 cells treated with Car@PtNP, with a marked increase in both early and late apoptotic cell populations. Furthermore, these results were confirmed by Hoescht and Rhodamin123 immunofluorescence staining, and significant mitochondrial dysfunction and apoptotic morphological changes were observed in treated cells. The findings underscore the promise of Car@PtNP as a novel chemotherapeutic approach, integrating the benefits of PtIV complexes and Car to enhance antitumor efficacy while mitigating the drawbacks of conventional platinum-based therapies.

Pancreatic duct strictures, which can arise from trauma, inflammation, or malignancy, often result in complications such as duct obstruction, pancreatic parenchymal hypertension, and ischemia. Endoscopic stenting is an effective therapeutic approach for managing these strictures However, traditional plastic pancreatic duct stents fail to conform to the physiological curvature of the pancreas, while metal pancreatic duct stents with flared ends reduce migration but are associated with complications such as de novo strictures. Additionally, plastic and metal pancreatic duct stents require surgical removal. Whereas biodegradable pancreatic duct stents present a promising alternative due to their superior biocompatibility and ability to decompose into non-toxic materials, potentially eliminating the need for additional surgeries. Despite these advantages, biodegradable pancreatic duct stents remain in the experiment stage. This review assesses current materials of pancreatic duct stents, and emphasize recent advancements in biodegradable options and emerging trends in clinical applications.

Knot stability and security are crucial factors in surgical suture performance, ensuring optimal tension distribution and minimizing the risk of wound dehiscence. The mechanical behavior of surgical knots is influenced by suture material properties, knot configuration, and environmental factors such as localized pH deviations, which can accelerate material degradation. This study investigates the impact of pH-induced degradation on the mechanical and optomechanical performance of square and surgeon's knots tied with Maxon and Monocryl sutures under acidic (pH 5) and neutral (pH 7) conditions. Stress-strain analysis and Mach-Zehnder interferometry were employed to assess Young's modulus, mechanical loss percentages, tensile strength, toughness, phase maps, and 3D refractive index profiles over 20 days. Young's modulus results revealed significant reductions in acidic conditions. Maxon's surgeon knot decreased from 516 MPa to 228 MPa, while Monocryl's surgeon knot dropped from 434 MPa to 132 MPa over 20 days. Mechanical loss was notably higher in acidic conditions, with Maxon's surgeon knot exhibiting a 65.30% reduction and Monocryl's surgeon knot showing an 82.3% decrease. Toughness declined similarly, particularly in knotted configurations. Phase maps revealed substantial structural distortion, especially in Monocryl's perpendicular orientation at pH 5, indicating severe degradation. 3D refractive index profiles demonstrated that Maxon maintained greater internal uniformity, while Monocryl showed pronounced structural disruption under acidic conditions. Maxon's stability under different pH conditions makes it suitable for long-term applications, while Monocryl's rapid degradation suggests its suitability for scenarios requiring faster material breakdown. These findings provide valuable insights for suture selection in diverse wound conditions.

Osteoarthritis (OA) has become a common degenerative joint disease, lacking clinical means to alleviate this disease. Melittin, taken from natural honeybee venom, possesses outstanding anti-inflammatory properties and has great potential to treat OA. However, its high toxicity and hemolytic properties limit its application. In this work, a biocompatible hydrogel was prepared from extracellular matrix (ECM) of rib cartilage, possessing fibrous mesh structure characteristics, which was beneficial for melittin loading. It was found that the use of ECM hydrogel loaded with melittin can reduce the intrinsic toxicity of melittin and prolong the release behavior, simultaneously. The in vitro study demonstrated that melittin-hydrogel could effectively inhibit phosphorylation-ERK/JNK, prevent the exacerbation of TNF-α-induced apoptosis in ATDC5 cells, and reduce their inflammatory markers, effectively alleviating OA and preventing cartilage degradation. Subsequently, in vivo studies have demonstrated that injecting melittin-hydrogel into the joint cavity of OA mice can effectively reduce cartilage degeneration. These findings suggest that melittin-hydrogel plays a critical role in the development of OA and may provide a therapeutic option for the treatment of OA disease.

The erosion and drug release behavior of an injectable hydrogel composed of ethoxylated trimethylolpropane tri-3-mercaptopropionate (ETTMP) and poly(ethylene glycol) diacrylate were determined under physiological conditions. Water and polymer mass changes were monitored over time to characterize the swelling/deswelling and erosion of the hydrogel tablets. Experimental data were collected for hydrogels with varying polymer fractions. These data were used to develop an empirical model to predict the eroding mass change and equilibrium water content across different compositions. Three easily detectable model drugs (methylene blue (MB), sulforhodamine 101, and chloroquine) were loaded into 25, 35, and 50 wt% polymer hydrogels to understand their drug release behavior. The gelation time and time for total drug release were dependent on the weight fraction of the polymer in the hydrogel and varied with the pH of the drug solutions, with more acidic drugs increasing gelation time. Complete drug release was not observed for MB because of the reaction with ETTMP thiol groups, demonstrating the importance of understanding the potential interactions between the drug and polymer. Drug-loaded hydrogels were also monitored for erosion and were found to swell more than their neat counterparts for all drugs tested, suggesting an effect of drug loading on the extent of hydrogel crosslinking.

Periodontitis seriously affects people's daily health, and the development of a non-antibiotic bio-adhesive with antimicrobial and periodontitis regeneration for periodontal pockets will effectively promote the treatment of periodontitis. In this study, we constructed a hybrid hydrogel (GelMA-BC-PL) by introducing aldehyde bacterial cellulose (BC) short nanofibers into the photosensitive hydrogel gelatin methacryloyl (GelMA), which binds to periodontal tissues to play an adhesive role through the Schiff base reaction, and further introducing -polylysine (PL), which could achieve the adhesive, antibacterial, and regenerative effect. Pigskin adhesion experiments showed that the adhesion of GelMA hydrogel to pigskin was only 0.39 N, while that of GelMA-BC-PL reached 1.42 N. The adhesion performance of the hydrogel was significantly improved by adding aldehyde BC nanofibers. Due to the introduction of PL, the antimicrobial properties of the hybrid hydrogel against two typical periodontitis bacteria (porphyromanas gingivalis and fusobacterium nucleatum), were significantly improved. Experiments with human periodontal membrane fibroblasts showed that the hybrid hydrogel had excellent cell spreading and proliferation promotion properties. The hybrid hydrogel simultaneously achieves adhesion, antimicrobial properties and promotes periodontal regeneration, which has great potential for application in the treatment of periodontitis diseases.

The success of tumor prosthesis relies on the preclusion of deep infection and local recurrence in limb sparing surgery. The orthopedic implants enabling to simultaneously possess the antibacterial function and anticancer ability have become a desirable local therapy in the treatment of bone cancer. In this regard, we proposed a promising concept of the sequential release in a dual-drug system by combing titania nanotubes and chitosan as drug nanoreservoirs and sustained release films, respectively. An electrochemical anodization technique, controlled by anodization voltage, electrolyte composition, and processing time, was used to fabricate self-ordered titania nanotubes on the titanium surface, with their lengths simply tuned by the processing time, for drug loading. Two drugs of cisplatin and vancomycin as model anticancer and antibiotic, respectively, were sequentially loaded in nanotubes to investigate the release kinetics. The release profiles of cisplatin and vancomycin were found to be related to the spatial positioning of each drug on the nanotubes. Such a release sequence can be attributed to the anisotropic diffusion of drugs from the nanotubes, which can be further sustained for over four weeks through chitosan coverage. The drug release behavior was first evaluated in water using ultraviolet-visible spectroscopy for the quantitative analysis of release kinetics over time. The influence of dual-drug-loaded nanotubes on the growth of staphylococcus aureus and osteogenic sarcoma in vitro was systematically evaluated for the therapeutic efficacy of bone cancer treatment. A high correlation between the viabilities of bacteria and cells and dual-drug release profiles was observed, indicating the feasibility of our nanotube-based concept utilizing a sequential release pattern to combat initial bacterial infection and prevent local recurrence.

Curcumin is a natural polyphenol extracted from plants that can interact with various molecular targets, including antioxidant, antibacterial, anticancer, and anti-aging activities. Due to its variety of pharmacological activities and large margin pf safety, curcumin has been used in the prevention and treatment of various diseases, such as Alzheimer's, heart, and rheumatic immune diseases. To develop curcumin eye drops that can be used as antioxidant and antibacterial agents after phacoemulsification, we have designed a nano-based drug delivery system to improve curcumin bioavailability and duration of action. We successfully prepared zeolitic imidazolate framework-8 (ZIF-8) coated with chitosan–liposome (Cur@ZIF-8/CS-Lip) for curcumin delivery. It can release curcumin for over 20 h in vitro and exhibits excellent biosafety, antioxidant, and antibacterial activities. Therefore, we hypothesized that Cur@ZIF-8/CS-Lip could reduce the incidence of oxidative stress and infection after cataract surgery.

The development of magnesium-based intraocular drug delivery devices holds significant promise for biomedical applications, particularly in treating wet age-related macular degeneration (AMD) using vascular endothelial growth factor inhibitors such as bevacizumab. Magnesium's rapid degradation, which can be finely tuned to achieve the controlled release required for AMD treatment, along with its well-established biocompatibility and biodegradable properties, positioning it as an ideal material for these applications. The study aimed to evaluate magnesium's potential as a carrier for ocular drug delivery systems by demontrating the stability of monoclonal antibodies, specifically bevacizumab, in the presence of magnesium corrosion products and the biocompatibility of these products with various cell lines, including murine fibroblasts (3T3), rat retinal Müller cells, and human retinal pigment epithelial cells (ARPE19). The stability of bevacizumab with pure magnesium (Mg) was investigated through an indirect enzyme-linked immunosorbent assay protocol, developed and customized for this specific aim. The biocompatibility of Mg corrosion products was assessed by toxicological evaluations through MTT and Trypan Blue Viability assays, along with cell cycle analysis. Results demonstrated no significant impact of Mg corrosion products on bevacizumab stability, with changes in mean values consistently below or equal to 10%. Furthermore, Mg extracts showed minimal cytotoxicity, as metabolic activity exceeded 80% across all cell lines, classified as Grade 0/1 cytotoxicity under ISO 10993-5 standards. Cell viability, proliferation, and morphology remained unaffected for up to 72 h of exposure. This study provides the first in vitro evaluation of bevacizumab's stability in the presence of magnesium corrosion products and its biocompatibility with retinal cell lines, laying the foundation for future ophthalmic research and underscoring magnesium's potential as a material for intraocular drug delivery systems.

Osteoporosis poses a significant public health challenge, necessitating advanced bone regeneration solutions. While gelatin methacrylate (GelMA) hydrogels show promise, conventional fabrication methods using aqueous two-phase systems (ATPS) often result in inconsistent mechanical properties and structural irregularities. This study presents an approach synthesizing new methods and parameters for bR-GelMA, utilizing stop-flow lithography (SFL) to fabricate highly elastic micro-particles incorporating bioactive glass particles. SFL, in contrast to ATPS, offers precise control over micro-particle formation, enabling the production of uniform and stable structures ideal for biomedical applications. The resulting elastic micro-particles demonstrate rapid degradation, enhanced cell proliferation, and improved mechanical strength without compromising flexibility. This innovative approach using SFL to fabricate GelMA-based micro-particles holds significant promise for bone regeneration and other critical therapeutic applications.

Temporary anchorage devices (TADs) have evolved as useful anchorage providers for orthodontic tooth movements. To improve the stability of TADs, a number of modifications on their surface have been developed and investigated. This review comprehensively summarizes recent findings of clinically applied surface modifications of TADs and compared the biological improvement of these modifications. We focused on sandblasting, large-grit, acid etching (SLA), anodic oxidation (AO) and ultraviolet photofunctionalization (UVP). In vitro, in vivo and clinical studies of these surface modifications on TADs with clear explanations, low possibility of bias and published in English were included. Studies demonstrated that SLA, AO and UVP enhance cell attachment, proliferation, and differentiation in vitro. The biocompatibility and osteoconductivity of TAD surface are improved in vivo. However, in clinical studies, the changes are generally not so impressive. Furthermore, this review highlights the promising potential in combinations of different modifications. In addition, some other surface modifications, for instance, the biomimetic calcium phosphate coating, deserve to be proposed as future strategies.

Bioprinting, an advanced additive manufacturing technology, enables the fabrication of complex, viable three-dimensional (3D) tissues using bioinks composed of biomaterials and cells. This technology has transformative applications in regenerative medicine, drug screening, disease modeling, and biohybrid robotics. In particular, in situ bioprinting has emerged as a promising approach for directly repairing damaged tissues or organs at the defect site. Unlike traditional 3D bioprinting, which is confined to flat surfaces and require complex equipment, in situ techniques accommodate irregular geometries, dynamic environments and simple apparatus, offering greater versatility for clinical applications. In situ bioprinting via hand-held devices prioritize flexibility, portability, and real-time adaptability while allowing clinicians to directly deposit bioinks in anatomically complex areas, making them cost-effective, accessible, and suitable for diverse environments, including field surgeries. This review explores the principles, advancements, and comparative advantages of robotic and hand-held in situ bioprinting, emphasizing their clinical relevance. While robotic systems excel in precision and scalability, hand-held bioprinters offer unparalleled flexibility, affordability, and ease of use, making them a valuable tool for personalized and minimally invasive tissue engineering. Future research should focus on improving biosafety, aseptic properties, and bioink formulations to optimize these technologies for widespread clinical adoption.

NanoMIPs are nanoscale molecularly imprinted polymers (MIPs) ranging in size between 30 to 300 nm offering a high affinity binding reagent as an alternative to antibodies. They are being extensively researched for applications in biological extraction, disease diagnostics and biosensors. Various methodologies for nanoMIP production have been reported demonstrating variable timescales required, sustainability, ease of synthesis and final yields. We report herein a fast (<2 h) method for one pot aqueous phase synthesis of nanoMIPs using an acrylamide-based monomer and N,N'-methylenebisacrylamide crosslinker. NanoMIPs were produced for a model protein template namely haemoglobin from bovine species. We demonstrate that nanoMIPs can be produced within 15 min. We investigated reaction quenching times between 5 and 20 min. Dynamic light scattering results demonstrate a distribution of particle sizes (30–900 nm) depending on reaction termination time, with hydrodynamic particle diameter increasing with increasing reaction time. We attribute this to not only particle growth due to polymer chain growth but based on AFM analysis, also a tendency (after reaction termination) for particles to agglomerate at longer reaction times. Batches of nanoMIPs ranging 400–800 nm, 200–400 nm and 100–200 nm were isolated using membrane filtration. The batches were captured serially on decreasing pore size microporous polycarbonate membranes (800–100 nm) and then released with sonication to isolate nanoMIP batches in the aforementioned ranges. Rebinding affinities of each batch were determined using electrochemical impedance spectroscopy, by first trapping nanoMIP particles within an electropolymerized thin layer. Binding constants determined for NanoMIPs using the E-MIP sensor approach are in good agreement with surface plasmon resonance results. We offer a rapid (<2 h) and scalable method for the mass production (40–80 mg per batch) of high affinity nanoMIPs.