Background316L stainless steel (SS) is widely used in biomedical implant applications because of its excellent mechanical properties, corrosion resistance, biocompatibility, and cost-effectiveness. However, its long-term performance in physiological environments is limited by localized corrosion, ion release, and inadequate surface interactions with biological tissues. Surface modification using Ti-based physical vapor deposition (PVD) coatings has emerged as a promising strategy to enhance the corrosion resistance and durability of implant materials.ObjectiveThis study aimed to investigate the effect of Ti-based PVD coatings, namely TiCoCr, TiN, and TiO2, on the corrosion behavior of 316L SS under simulated physiological conditions.MethodsTiCoCr, TiN, and TiO2 coatings were deposited onto 316L SS substrates using the PVD technique. The corrosion performance of the coated and uncoated samples was evaluated in phosphate-buffered saline (PBS), Hanks' solution, and Ringer's solution at 37 °C. Electrochemical corrosion parameters, including corrosion potential and corrosion current density, were analyzed to assess the effectiveness of the coatings.ResultsAll Ti-based coatings improved the corrosion resistance of 316L SS compared with the uncoated substrate. Among the investigated coatings, the TiCoCr coating deposited for 90 min exhibited the best corrosion performance. In Ringer's solution, the coating showed a corrosion potential of -0.0504 V and a corrosion current density of 4.74 × 10-6 A/cm2. In Hanks' solution, the same coating demonstrated a corrosion potential of -0.1815 V and a corrosion current density of 5.0537 × 10-6 A/cm2. The enhanced corrosion resistance was attributed to the protective and stable nature of the Ti-based coating layer.ConclusionThe TiCoCr, TiN, and TiO2 PVD coatings significantly enhanced the corrosion resistance of 316L SS in simulated physiological environments. Among them, the TiCoCr coating demonstrated superior corrosion protection, indicating its strong potential for improving the long-term reliability and performance of biomedical implants.
BackgroundAllergic conjunctivitis is an inflammatory disorder of the conjunctiva triggered by allergens. Although topical eye drops are widely used, their efficacy is limited by rapid precorneal clearance and low ocular bioavailability. Hyaluronic acid (HA)-based nanoparticles may prolong ocular residence time and improve drug delivery.ObjectiveThis study aimed to develop and evaluate chitosan- and polyethylenimine (PEI)-cross-linked HA nanoparticles to improve drug encapsulation efficiency and achieve sustained release of diclofenac sodium for allergic conjunctivitis.MethodsHA nanoparticles were prepared by EDC/sulfo-NHS-mediated cross-linking with chitosan or PEI. Nanoparticle properties were characterized by FTIR, 1H-NMR, DLS, and HRTEM. Encapsulation efficiency, in vitro drug release, and cytocompatibility in SIRC cells were evaluated.ResultsFTIR and 1H-NMR analyses confirmed successful nanoparticle formation, cross-linking, and drug incorporation. H1P1-01DS exhibited a particle size of approximately 170 nm and a significantly higher encapsulation efficiency (82.0%) than the HA-chitosan formulations. Drug release followed a biphasic profile, with H1P1-01DS achieving approximately 90% cumulative release within 180 min, compared with 68-83% for HA-chitosan formulations. WST-1 assays demonstrated favorable cytocompatibility across all formulations, although cell viability decreased in a dose-dependent manner at higher concentrations.ConclusionThe HA-PEI nanoparticle formulation (H1P1-01DS) demonstrated sustained drug release, high encapsulation efficiency, and favorable biocompatibility, indicating its potential as a long-acting ocular drug delivery system for allergic conjunctivitis.
BackgroundHydroxyapatite (HA) coatings on titanium (Ti) implants are widely studied owing to their biocompatibility and osteoconductivity. However, the effect of substrate temperature during flame spraying on coating performance remains unclear.ObjectiveThis study investigated the influence of substrate temperature on the microstructure, mechanical properties, and electrochemical behavior of flame-sprayed HA coatings on Ti implants.MethodsHA coatings were deposited on commercially pure Ti Grade 2 substrates by flame spraying at room temperature (RT) and 300 °C. The coatings were characterized by XRD, FTIR, XPS, SEM, and EDS. Surface roughness, adhesion strength, abrasion resistance, potentiodynamic polarization, and electrochemical impedance spectroscopy were evaluated.ResultsSubstrate heating at 300 °C modified the crystalline phase composition and slightly increased the apparent HA crystallite size and crystalline peak index. The 300 °C coating exhibited a more compact surface morphology, higher adhesion strength, lower abrasion-induced mass loss, lower corrosion current density, and higher charge transfer resistance than the RT coating.ConclusionSubstrate heating at 300 °C improved the mechanical durability and corrosion resistance of flame-sprayed HA coatings, indicating its usefulness for enhancing Ti implant coating performance.
In this study, the efficacy of pinus sp. nanocellulose membranes, with and without silver nanoparticles, was evaluated in the treatment of experimental burns in rabbits. A total of twenty animals were used, each receiving three standardized dorsal burns of equal size, treated with either a simple dressing (negative control), a nanocellulose membrane without silver, or a nanocellulose membrane containing silver. Healing was monitored through macroscopic and microscopic analyses performed on days 3, 7, 14, and 30 after the induction of the burns. The findings demonstrated that nanocellulose membranes effectively promoted tissue repair and skin regeneration, with evidence of fibroblast activity, collagen deposition, and neovascularization throughout the healing process. The incorporation of silver nanoparticles showed potential to enhance early wound contraction, although all groups achieved complete re-epithelialization by the end of the experimental period. While the addition of silver may contribute to antimicrobial protection and early tissue response, further studies are required to confirm its role in accelerating the healing process and to better elucidate its mechanisms of action. Overall, pinus sp. nanocellulose membranes represent a safe and effective alternative for the treatment of burns, supporting their potential application in clinical practice.
BackgroundWith population aging and an increase in sports injuries, articular cartilage wear has become increasingly severe, significantly impairing patients' quality of life. Cross-shear motion is a common loading pattern in daily joint activities, yet its effects on cartilage and counterpart materials remain insufficiently investigated.ObjectiveTo investigate the wear behavior and underlying mechanisms of articular cartilage under cross-shear motion, and to compare the wear resistance of different artificial joint materials, so as to propose material optimization strategies suitable for this motion pattern.MethodsFresh bovine knee femoral cartilage was used to simulate the human cartilage environment under various cross-shear conditions and loading regimes. Stepwise loading, microhardness testing, cartilage compression deformation measurements, and surface wettability tests were performed to systematically analyze the tribological characteristics and wear mechanisms of each material. The evaluated materials included CoCrMo, ultra-high molecular weight polyethylene, and polyether-ether-ketone (PEEK).ResultsCross-shear motion significantly increased wear in all materials. CoCrMo exhibited the largest increase (ΔK = 230.51 ± 25.67%), while PEEK showed the smallest increase in wear rate (138.37%). No significant linear correlation was found between material hardness and cross-shear wear rate (r = -0.32, p > 0.05). In terms of dynamic wettability, PEEK performed best, with a hysteresis angle 38.46% lower than that of natural cartilage, and its energy dissipation parameters were close to those of natural cartilage, indicating the best cartilage compatibility.ConclusionUnder cross-shear conditions, PEEK demonstrates the best overall wear resistance and biomechanical compatibility, suggesting its potential as a promising material for joint repair. The wear mechanisms revealed in this study provide experimental evidence and reference for performance optimization and clinical selection of artificial joint materials.
BACKGROUND:Bone grafts are commonly employed for the reconstruction of bone defects, and dentin has been reported as a promising bone graft material that supports early graft vascularization. However, clinical applications typically involve a prolonged demineralization process prior to the use of dentin samples. OBJECTIVE:This in vitro study aimed to evaluate the biological properties of dentin samples without demineralization procedure. METHODS:Dentin extract (DE) was obtained by mechanically crushing dentin samples, dissolving and filtering the mixture. Enzyme-linked immunosorbent assay (ELISA) was first performed to identify cytokines released from DE, revealing that TGF-β was notably enriched. Subsequently, cell viability, wound healing, and tube formation assays were conducted to assess the effects of DE on cell proliferation, migration, and angiogenic potential in human umbilical vein endothelial cells (HUVECs). RESULTS:The in vitro results demonstrated that DE significantly enhanced HUVEC proliferation, migration, and tube formation capabilities. These effects were markedly attenuated by treatment with the Notch pathway inhibitor DAPT and the tyrosine kinase inhibitor N-Desethyl Sunitinib. RT-qPCR and Western blot analyses further revealed that DAPT and N-Desethyl Sunitinib, downregulated the mRNA and protein expression of markers associated with cell migration and angiogenesis signaling pathways, and these effects were significantly reversed by treatment of DE without demineralization. CONCLUSION:In conclusion, this study demonstrates that DE, without demineralization, promotes cell proliferation, migration, and angiogenesis in HUVECs via the Notch and VEGF/VEGFR2 signaling pathways. These findings suggest that dentin, without the need for demineralization, could serve as a viable alternative to conventional bone graft materials, offering a more streamlined process for regenerative surgery.
De-antigenization treatments in allogeneic bone grafting affect the compressive properties of bone materials, while synthetic 3D-printed scaffolds often overlook trabecular structural influences. This study investigates how de-antigenization impacts the hardness and compressive strength of bovine cancellous bone and explores the relationship between trabecular structural parameters and mechanical properties, aiming to optimize antigen removal while preserving mechanical integrity and guiding synthetic bone design. In this study, the hardness, compressive strength, and elastic modulus of bovine cancellous bone were analyzed after degreasing and deproteinization. Structural parameters (porosity, trabecular anisotropy, fractal dimensions) were obtained via CT scanning, and their effects on compressive properties were evaluated. The study yielded three findings:1. Deproteinization weakened the mechanical properties of bovine cancellous bone more significantly than degreasing. 2. When both deproteinization and degreasing are required, conducting degreasing before deproteinization can reduce the loss of mechanical properties. 3. Compressive strength is positively correlated with trabecular anisotropy and negatively correlated with trabecular thickness. To preserve the compressive strength and hardness of xenograft bone materials, degreasing should be performed before deproteinization during de-antigenization. In the design of 3D-printed bone scaffolds, the compressive strength can be modulated by adjusting the anisotropy of scaffold units. This approach enables personalized scaffold design tailored to the specific needs of individual patients, improving clinical outcomes.
Photoacoustic technology can non-invasively obtain the temperature and pressure of tissues, holding great promise for applications in the laser thermal ablation of pigmented skin diseases. The coefficient of thermal expansion is the primary source of temperature sensitivity in photoacoustic technology. In this paper, a non-contact full-field strain measurement system based on temperature-variable three-dimensional digital image correlation is used to measure the variation of the thermal expansion coefficient of melanin in the retinal pigment epithelium layer of porcine eyes. It is found that the thermal strain of melanin exhibits non-uniformity and nonlinear increase in radial Angle and circular domain. Before the glass-transition temperature (49°C), the average coefficients of thermal expansion for concentric circular regions and different radial directions are 4.14 × 10-4 K-1 and 3.82 × 10-4 K-1, respectively. Approximating the thermal expansion coefficient of melanin with that of graphite leads to a large error, with a difference of two orders of magnitude.
ObjectiveThe popularity of brushite cement (BrC) in bone regeneration is related to its biocompatibility and favorable resorption properties. Nevertheless, it has poor clinical performance due to quick settling, lack of mechanical strength, and anti-bacterial activity. This paper offered the research on the impact of adding chitosan-selenium nanoparticles (CS-SeNPs) into BrC to improve its mechanical, physical, and biological characteristics.MethodsCS-SeNPs were added to BrC at 1 and 2 wt.% concentration. Scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD) and fourier transform infrared spectroscopy (FTIR) were used to characterize the modified materials. Physical and mechanical properties were evaluated through mass-loss investigations, setting time, and mechanical properties, shear bond strength [SBS], diametral compressive strength [DCS] and biaxial flexural strength [BFS]. The antibacterial activity, and cytocompatibility were also tested.ResultsThe use of CS-SeNPs enhanced BrC crystallinity, mechanical strength and antibacterial activities. SBS, DCS as well as BFS improved considerably with nanoparticles inclusion. The highest mass loss was observed at 1 wt.% CS-SeNP after 48 h and the setting times were longer in comparison with the control. The zone of inhibition and decrease in optical density were seen significant in 1 wt.% group, which indicates superior antibacterial activity. The biocompatibility tests showed moderate cytotoxicity at the higher concentrations.ConclusionThe use of up to 2 wt.% CS-SeNPs increases the structural, mechanical, and antibacterial behavior of brushite cement considerably without deteriorating its fundamental features. This engineered formulations promises to be applied in the regeneration of bones that need a greater mechanical strength and antimicrobial coverage.
BackgroundYttria-stabilized zirconia (YSZ) represents a promising alternative to titanium for dental and orthopedic implants owing to its mechanical strength and esthetics. However, its bioinertness limits osteoconductivity. Although hydroxyapatite (HAp) coatings can enhance osteointegration, uniform deposition of morphology-controlled HAp on YSZ remains challenging to achieve, limiting implant optimization.ObjectivesThis study was aimed at the uniform deposition of morphology-controlled HAp on YSZ using electrostatic layer-by-layer (LBL) assembly to improve biological performance.MethodsPlate-like HAp was hydrothermally synthesized using dodecanedioic acid and surface-modified with poly(diallyldimethylammonium chloride) and poly(sodium 4-styrenesulfonate). YSZ discs were similarly charge-modified to enable electrostatic adsorption of HAp. Samples were evaluated using scanning electron microscopy, energy-dispersive X-ray spectroscopy, Fourier-transform infrared spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and wettability tests. Osteogenic responses were assessed using MC3T3-E1 cells through alkaline phosphatase (ALP) activity and Alizarin Red S staining.ResultsNegatively charged HAp was uniformly deposited on positively charged YSZ, forming a homogeneous coating. Characterization confirmed successful HAp deposition and improved hydrophilicity. HAp/YSZ composites enhanced osteogenic differentiation, exhibiting higher ALP activity and greater calcium deposition than YSZ.ConclusionLBL-mediated deposition of morphology-controlled HAp enables uniform coating and enhanced osteogenic activity on YSZ, facilitating advances in next-generation bioactive zirconia implants.
BACKGROUND:Glioblastoma multiforme (GBM) is the most common type of brain tumor and it is considered as one of the most aggressive malignancies (1.5 years of survival rate). OBJECTIVE:Determine the antitumor potential of bismuth lipophilic nanoparticles (BisBAL NP) on a human glioblastoma cell-line. METHODS:BisBAL NP were characterized by scanning electron microscopy (SEM). BisBAL NP entry and intracellular distribution on U-87 MG cells were observed by transmission electron microscopy (TEM). The effect of BisBAL NP on tumor cells was evaluated by MTT assay (IC50 value), Calcein AM staining, Live/dead assay, apoptosis quantification, and comet assay. RESULTS:BisBAL NP-induced cytotoxicity more efficient than temozolomide (TMZ). The IC50 value of BisBAL NP was 12.7 µM. For the first time, direct interaction between BisBAL NP and plasmatic U-87 MG cell membrane was obtained by TEM. Calcein AM assay revealed loss of permeability of tumor cells after 24 h-exposure to 25 µM of BisBAL NP. 25 µM of BisBAL induced 48.5% of apoptosis, while 50 µM of BisBAL induced a higher rate of apoptosis 77.2%. CONCLUSION:BisBAL NP inhibited U-87 MG cell growth through membrane attack and loss membrane permeability, apoptosis induction and later promoting genotoxicity among tumor cells.
A composite of polyvinyl alcohol (PVA) and beta-tricalcium phosphate (β-TCP) was synthesized as a biomaterial filament for 3D printers and its analytical and chemical evaluation was performed. PVA powder and β-TCP were mixed in the range of 0-20 wt% and hot-melt extruded at 200 °C using a single-screw extruder. Comprehensive material characterization of the synthesized filament was performed by powder X-ray diffraction (XRD), near-infrared spectroscopy (NIR), and scanning electron microscopy (SEM). XRD analysis confirmed that the amorphous nature of PVA and the crystalline nature of β-TCP coexisted and the physical mixture state was well maintained. In near-infrared spectroscopy, concentration-dependent spectral changes were observed by normalization, and principal component analysis showed that the first principal component explained 85.6% of the variance. In machine learning regression analysis, partial least squares regression (PLS), random forest (RF), and support vector machine (SVM) were compared, and SVM achieved the best prediction accuracy (R2 = 0.910). SEM observations confirmed streaky structures along the extrusion direction and uniform dispersion of β-TCP particles. This study demonstrated that a combined NIR spectroscopy and machine learning approach is effective as a non-destructive quality evaluation technique for composite filaments for 3D printing. This technique enables real-time composition monitoring and quality control of biomaterial filaments, and is expected to be applied to the manufacturing of patient-specific biomedical devices.
BackgroundMonopolar Radiofrequency uses high-frequency waves to generate heat for skin tightening and tissue repair. However, individual fat layer thickness variation causes uneven radiofrequency (RF) penetration and heat thresholds, compromising personalized results.ObjectiveThe purpose of this study is to analyze the temperature distribution of tissues with different fat thickness after radio frequency treatment and the experimental temperature distribution and tissue changes of pork tissues in vitro by finite element analysis and in vitro experiment verification, so as to achieve appropriate energy parameters for different individuals.MethodsA two-dimensional bio-thermal model including epidermis, dermis and subcutaneous tissue was developed in COMSOL Multiphysics 6.2. Four fat thicknesses (2, 4, 6, and 8 mm) were simulated to assess their impact on dermal temperature distribution during 6.78 MHz, 120 W radiofrequency exposure. The electromagnetic-thermal coupling effects were validated through in vitro experiments.ResultsExperimental results validate the simulations, demonstrating consistent thermal trends across fat thicknesses (2-8 mm). Post-treatment intratissue temperatures reached 69 °C (2 mm), 60 °C (4 mm), 55 °C (6 mm), and 45 °C (8 mm), all within epidermal safety limits.ConclusionThe results show that the energy parameters need to be adjusted according to the thickness of adipose tissue during radiofrequency therapy, and higher energy or longer treatment time may be needed for the treatment site with thicker adipose tissue to achieve the expected effect.
BACKGROUND:Vertically oriented femoral neck fractures are a challenge for orthopedic surgeons, and the complication rates are also high. Recently, several innovative devices have been proposed, such as the proximal femoral bionic nail, InterTAN, and medial buttress plate combined with cannulated screws, to increase the stability of fixation. However, the differences among these innovative devices need to be addressed. OBJECTIVE:This study aimed to compare the stability of the proximal femoral bionic nail, InterTAN, and medial buttress plate combined with cannulated screws for vertically oriented femoral neck fractures. Additionally, traditional fixation devices-including three parallel cannulated screws, a compression hip screw system, and a proximal femoral nail-were included for comparison, resulting in a total of six distinct devices evaluated in this study. METHODS:A finite element model of a femoral neck fracture fixed with the six internal fixation devices was created. Furthermore, two different fracture conditions-with and without a 1-mm fracture gap-were considered. The maximum loading during level walking was applied to the model for comparison. RESULTS:The results indicated that the InterTAN has the best ability to maintain the gap and prevent collapse. Under the fracture gap condition, the peak displacement of the femoral head was smaller in the innovative devices compared to the traditional ones. Specifically, the peak displacements were 1.98 mm for the medial buttress plate combined with cannulated screws, 2.12 mm for the proximal femoral bionic nail, and 1.16 mm for the InterTAN system. The von Mises stress in the medial buttress plate was also the highest among the devices, with values of 1000 MPa with the gap and 1477 MPa without the gap. CONCLUSION:Based on the present results, the medial buttress plate combined with cannulated screws, proximal femoral bionic nail, and InterTAN are recommended for cases without a fracture gap, while the InterTAN is recommended for cases with a fracture gap to prevent bone shortening.
BackgroundCardiovascular diseases are the leading cause of mortality worldwide, with coronary artery bypass grafting being the most effective treatment for severe cases. While autografts are preferred, donor veins are often limited. Human umbilical arteries (hUAs) show promise as an alternative. However, to make vascular graft by decellularization, a traditional chemical method can damage tissue structure and function.ObjectiveThis study aims to evaluate the shortening of treatment time and the hUA decellularization efficiency of the perfusion bioreactor systems.MethodshUAs were perfused with 1% Triton X-100 for 6 h, followed by two different concentrations of (0.5% and 1%) SDS for 18 h, and subsequently subjected to a washing procedure. The decellularization process was evaluated using histological staining and DNA quantification, along with tests for cytotoxicity, cell adhesion and proliferation.ResultsThe 0.5% SDS protocol proved most effective, reducing residual DNA to below 50 ng/mg of dry weight while preserving collagen structure. It showed no cytotoxicity to L929 cells, SEM analysis confirmed human umbilical vein endothelial cell (HUVEC) attachment and CCK-8 testing showed promoted HUVECs proliferation.ConclusionThe decellularization protocol of perfusing through 1% TX for 6 h and 0.5% SDS for 18 h through the perfusion bioreactor system is efficient in the intact hUAs tissue. This sets the stage for future in vivo studies and potential clinical applications.
BackgroundResin composite restorations exhibit dimensional changes in the oral environment due to polymerization reaction and/or water sorption, which generates stresses in the surrounding tooth structures. The state of stress may differ between self-adhesive resin composites (SARCs) and conventional resin composites because only SARCs contain hydrophilic monomers.ObjectiveThe objective of this study was to evaluate the influence of water sorption on polymerization stresses of SARCs.MethodsCracks were introduced near a cylindrical hole in a glass disk, and their lengths were measured. The hole was filled with the composites. The crack lengths were repeatedly measured during 1-week water storage 37°C. Stresses at the composite-glass interface were calculated from the crack lengths and fracture toughness of the glass. Flexural moduli, water sorption and solubility of composites were also measured.ResultsPolymerization stresses of SARCs were equivalent to or less than that of a conventional composite generating relatively little stress. Significant reduction of stress occurred between 1-h and 1-day water storage in all composites. This reduction tended to be more noticeable with a larger decrease in modulus and/or larger water sorption.ConclusionsQuicker and/or larger stress reduction were considered to be beneficial for the longevity of SARC restorations.
BackgroundMacrophages phagocytose large amounts of cholesterol to form foam cells that can aggravate inflammation and further promote the development of atherosclerotic plaque.ObjectiveTo develop novel nanocarriers targeting atherosclerosis-associated macrophages.MethodsCD-G5 was obtained by modifying β-CD onto PAMAM G5.0, and subsequently PEG2000 was used as a linker arm to modify mannose onto PAMAM G5.0 of CD-G5 to obtain CD-G5-PEG-Man. CD-G5-PEG-Man was structurally characterized and evaluated in vitro for its cell biological functions.ResultsCD-G5-PEG-Man had an average particle size of 110 nm and a regular spherical morphology. CD-G5-PEG-Man showed no significant toxicity to macrophages at all the experimental concentration gradients. Macrophages showed stronger uptake of the fluorescently labelled nanoparticle CD-G5-PEG-Man-FITC than CD-G5-FITC, and the fluorescence weakened with increasing free mannose. Intracellular BODIY-cholesterol fluorescence intensity was weaker in the 200 nM CD-G5-PEG-Man treatment group than in the 100 µM HP-β-CD, 100 nM CD-G5-PEG-Man, and DMSO treatment groups. The higher the amount of β-CD on the CD-G5-PEG-Man, the lower the fluorescence intensity of intracellular BODIY-cholesterol.ConclusionA biosafety nanocarrier, CD-G5-PEG-Man, was successfully developed, in which mannose specifically targets macrophages via mannose receptors on macrophages, and β-CD synergistically promotes cholesterol efflux from macrophages.
BackgroundVarious methods have been reported for improving the water-insoluble drugs in oral administration formulations. Among them, amorphization has been attracting attention and developed as a method for solubilizing API (active pharmaceutical ingredient)s by changing their physicochemical properties. Molecular complexation is also known as a method for solubilizing APIs by synthesizing cocrystals, etc. Co-amorphization, which achieves both molecular complexation and amorphization, is effective and has attracted attention. Thus, co-amorphization has been proven to be an effective approach to solubilization.ObjectiveThis study aims to improve the solubility of lumefantrine, used here as a model compound, through co-amorphization with deoxycholic acid.SignificanceThe physicochemical properties are an important factor in developing pharmaceutical ingredients. Hydrogen-bonded co-amorphization has gained attention as a method to enhance the physicochemical properties of hydrophobic drugs.MethodsThe co-amorphous Lumefantrine-deoxycholic acid system was prepared using a mechanochemical synthesis method based on ball milling. The synthesis process was monitored by powder X-ray diffraction and near-infrared spectroscopy. The products and materials were analyzed by thermal analysis.ResultsSpectroscopic analysis revealed that the two molecules were complexed through intermolecular hydrogen bonding interactions. The produced co-amorphous has no melting point was found by thermal analysis.ConclusionsProcess monitoring also indicated the presence of a metastable crystalline Lumefantrine (LMF) intermediate.
BackgroundBone filling materials that match the mechanical properties of normal cancellous bone may be more suitable for vertebroplasty to improve the complications caused by osteoporosis.ObjectiveTo prepare and evaluate a new bone filling material (NBFM) that matches the mechanical properties of normal cancellous bone for vertebroplasty.MethodsA new bone filling material (NBFM) was prepared and its biomechanical properties were compared with those of polymethyl methacrylate (PMMA) bone filling material commonly used in clinical vertebroplasty. Finite element analysis was conducted to compare the biomechanical differences between NBFM and PMMA. The lumbar spine model's biomechanical differences were assessed under four different loading conditions: flexion, extension, left flexion, and right flexion.ResultsThe NBFM demonstrated biomechanical properties more closely matching normal cancellous bone compared to PMMA. The finite element analysis revealed that the lumbar spine model with NBFM exhibited improved biomechanical behavior under the specified loading conditions.Conclusion:Bone filling materials that match the mechanical properties of normal cancellous bone, such as the newly developed NBFM, are more suitable for vertebroplasty and may help reduce complications associated with osteoporosis.
Background: Aqueous solubility of pharmaceuticals is a factor as it is directly associated with bioavailability; accordingly, strategies to enhance solubility have been well investigated. Objectives: The purpose of this study was to determine the effects of coamorphization on meloxicam (MX) and saccharine (SA) mixtures. Methods: An equimolar mixture of MX and SA was ground for 4 h at 300 rpm. The obtained samples were evaluated using Fourier-transform mid-infrared spectroscopy, Fourier transform near-infrared spectroscopy, powder X-ray diffraction (PXRD), and thermal analysis. No molecular interactions were observed in the physical mixture sample. The ground samples showed broad peaks in the PXRD patterns and an exothermic peak at an early temperature. Results: The results suggested that the grinding process transformed MX and SA into a coamorphous phase. The attenuated total reflection - IR spectra exhibited new peaks at 1719 cm −1 and 1398 cm −1 , and the NH peak disappeared with grinding time. Measurement data of MX and SA ground sample suggested they constructed coamorphous phase. Conclusion: It was indicated by multivariate analysis that the formation of the MX/SA coamorphous system occurred in a two-step process.
