Biosurface and Biotribology最新文献

In this study, the authors designed a paper-based electrochemical immunodevice modified with copper embedded in copper sulphide hollow nanocages wrapped with Au nanoparticles (Cu@CuS@Au NPs) for the specific detection of prostate-specific antigen (PSA), aiming to advance point-of-care testing. The large specific surface area of Cu@CuS nanocages enables efficient capture of biotin antibodies, leading to the direct amplification of the signal through the inhibition of electron transport in the redox process of Cu, eliminating the need for universal redox electron mediators. Additionally, Au NPs on the surface of Cu@CuS can accelerate charge transfer and conjugate with anti-PSA. The hierarchical morphology and structure of Cu@CuS nanocages were characterised using scanning electron microscopy and transmission electron microscopy. The fabrication process of the immunodevice was monitored using cyclic voltammetry and electrochemical impedance spectroscopy analyses. PSA was sensitively detected using differential pulse voltammetry on this proposed immunodevice within a linear range from 0 to 100 ng/ml (R² = 0.996), achieving a low detection limit of 0.077 ng/ml. In addition, the practicality of the developed immunosensor has been proven by successfully detecting PSA in human serum samples obtained from clinical settings. The integration of electrochemical sensors and microfluidic devices holds promise for developing cost-effective approaches in clinical immunoassays.

Additive manufacturing has enabled the creation of 3D porous metallic medical materials, crucial for enhancing cell ingrowth and tissue integration. However, despite extensive research on optimising pore size, inconsistencies persist in achieving optimal cells and tissues adhesion. In this study, the authors show that cell attachment and proliferation are hindered by the formation of bubbles within the pores, which may act as physical barriers. The authors fabricated porous titanium (Ti) and tantalum (Ta) scaffolds by selective laser melting and investigated the effects of bubble entrapment on cell adhesion and proliferation. The authors’ results demonstrate that bubble removal significantly enhanced cell integration. These results indicate the importance of both geometrical design and microenvironmental conditions to prevent bubble formation, ensuring cell adhesion and tissue integration in the development of next-generation porous metallic scaffolds.

As a third-generation titanium alloy, Ti13Nb13Zr is widely used in the field of biomedicine due to its advantages such as low elastic modulus, high strength, high toughness, high fatigue strength, corrosion resistance, and good biocompatibility. However, the biological inertness of Ti13Nb13Zr alloy limit their wide application as biomedical implant materials. In this study, the bioactive TiO₂ nanotubes was prepared on Ti13Nb13Zr alloy by anodisation and heat treatment method. The bioactivity of Ti13Nb13Zr was evaluated by immersing the samples into the simulated body fluid for 20 days. Results show that the Ti13Nb13Zr alloy coated with anatase nanotubes has the superior ability of hydroxyapatite formation.

Friction between the contact lens (CL) and the corneal or conjunctival surfaces is considered one of key factors in triggering CL-associated adverse effects. However, the relationship between friction properties and these effects remains unclear. Traditional measurement methods often fail to replicate real-life conditions, thereby highlighting the need for more effective apparatus. In this study, the authors developed an optimised pendulum apparatus integrated with an inclinometer to enhance the measurement of CL friction coefficients, thereby improving its precision and relevance to clinical settings. This new design allows for faster and easier calculation of the friction coefficient based on the amplitude decay per libration cycle, surpassing the accuracy of previous video-based methods. The pendulum's hemisphere component was made from ethylene–propylene–diene monomer rubber (EPDM) 30, which has an elastic modulus similar to that of a human eyeball, creating a measurement environment that closely mimics real-world usage. The authors optimised the apparatus by evaluating the effects of hemisphere stiffness and saline volume on the friction coefficient. Measurements of multiple lenses recorded by the authors, particularly Lens A, made of narafilcon A, revealed significant consistency across different hemisphere materials with an optimal saline volume of 150 μL yielding a friction coefficient of 0.026 ± 0.003. No statistically significant differences in the friction coefficients were found across variations in the lens base curve, diameter, centre thickness, or power. This improved apparatus demonstrates the capability of effectively measuring friction coefficients under conditions that simulate clinical usage, providing rapid and reliable results. The findings validate the apparatus and suggest its potential for broader applications in assessing CL properties, thereby facilitating future research on the material characteristics and safety of various CLs, including decorative lenses.

The purpose of this research is to develop data-driven machine learning (ML) models capable of estimating the specific wear rate of ultra-high molecular weight polyethylene (UHMWPE) used in hip replacement implants. The results of the data-driven models are demonstrating a high level of consistency with the experimental findings acquired from the pin-on-disk (POD) trials. With a performance evaluation of 0.06 mean absolute error (MAE), 0.17 Root Mean Square Error (RMSE), and 0.96 R², the Random Forest Regression is found to be the best model. Another machine learning model, called Gradient Boosting Regression, is also found to possess satisfactory predictive performance by having an MAE of 0.09, RMSE of 0.24, and R² of 0.96. According to the findings of a parametric analysis that made use of an ML model, the surface texture geometry has a substantial dependence on the wear behaviour of UHMWPE bearings that are used in hip replacement implants. This strategy has the potential to enhance experiment design and lessen the necessity for time-consuming POD trials for the purpose of assessing the wear of hip replacement implants.

Hydrogels, characterised as highly hydrophilic three-dimensional polymer networks, have gained increasing attention due to their unique physicochemical properties, finding applications in various fields. Natural polymer hydrogels exhibit higher biocompatibility and biodegradability compared to traditional synthetic polymer hydrogels. Proteins, being the principal materials of natural polymer hydrogels, bear numerous modifiable functional groups. The resultant hydrogel possesses responsiveness, adjustable degradability, and underway as an excellent biomaterial. Seven common raw materials used to construct protein hydrogels are introduced. In terms of comparing natural polymer hydrogels with traditional synthetic polymer hydrogels, the authors conduct a detailed analysis and comparison, highlighting the advantages of natural polymer hydrogels in terms of biocompatibility and biodegradability, and summarising their characteristics. The authors also address the limitations of various protein hydrogels and list existing strengthening cross-linking strategies, proposing new insights to overcome the application limits of protein hydrogels. Additionally, the applications of protein hydrogels in drug delivery, biosensing, bio-inks and tissue engineering are discussed. The authors conclude by summarising the current challenges faced by protein hydrogels and prospecting its future development.

Improving energy efficiency and cost reduction is a perennial challenge in engineering. Natural biological systems have evolved unique functional surfaces or special physiological functions over centuries to adapt to their complex environments. Among these biological wonders, fish, one of the oldest vertebrate groups, has garnered significant attention due to its exceptional fluid dynamics capabilities. Researchers are actively exploring the potential of fish skin's distinctive structural and material characteristics in reducing resistance. In this study, models of biomimetic imbricated fish scale are established, and the evolution characteristics of the flow field and drag reduction performance on these bionic surfaces are investigated. The results showed a close relationship between the high–low velocity stripes generated and the fluid motion by the imbricated fish scale surface. The stripes' prominence increases with the spacing of the adjacent scales and tilt angle of the fish scale, and the velocity amplitude of the stripes decreases as the exposed length of the imbricated fish scale surface increases. Moreover, the biomimetic imbricated fish scale surface can decrease the velocity gradient and thereby reduce the wall shear stress. The insights gained from the fish skin-inspired imbricated fish surface provide valuable perspectives for an in-depth analysis of fish hydrodynamics and offer fresh inspiration for drag reduction and antifouling strategies in engineering applications.

Bionic lubricant materials are a class of materials inspired by natural organisms and offer excellent lubrication properties and biocompatibility. In the field of sports medicine, their application opens up new possibilities for the prevention and treatment of sports-related diseases. The authors will introduce the existing theoretical models of friction in the locomotor system, the characteristics and advantages of biomimetic lubrication materials and discuss in depth their applications in the field of sports medicine. The development of bionic lubrication materials opens up unprecedented opportunities for sports medicine to provide more effective and long-lasting treatment options for patients.

Due to trauma and disease, bone defects endanger the healthy life of human beings. At present, the gold standard for bone defect repair is still autologous bone transplantation and allogeneic bone transplantation. However, its insufficient source, potential disease transmission and immune rejection limit its clinical application. Therefore, the development of bone repair materials plays an important role in promoting bone repair. As the interface between material and tissue, the surface of the material plays an important role in the reaction after implantation, which determines the effectiveness of defect repair treatment. With the development of surface engineering and technology, bone repair materials have developed from biological inertia to biological activity by endowing various biological functions by controlling the composition, topological morphology and structure of the material surface etc. The inspired biofunctionalisation of material surface includes the capacities of inducing osteogenesis, promoting angiogenesis, antibacterial, immune regulation etc., as well as integration of postoperative repair and treatment. The authors review the biofunctionalisation of biomaterial surface and the inspired biological effects for bone repair, mainly including physical and chemical properties of material surface to regulate osteogenesis, and functional strategy of bone repair material surface.

Biomaterials with exceptional performance are crucial for addressing the challenges of complex bone regeneration. Compared with traditional three-dimensional scaffolds, injectable microspheres enable new strategies for the treatment of irregular bone defects. Biodegradable poly (lactic-co-glycolic acid) has found widespread applications as microcarriers of drugs, proteins, and other active macromolecules. Applied to the surface of poly (lactic-co-glycolic acid) cage-like structures (PLGA-CAS), hydroxyapatite (HA) effectively reduces inflammation while enhancing biological effects. In this study, we loaded the surface of PLGA-CAS with micro- and nano-hydroxyapatite particles, referred to as μHA/PLGA-CAS and nHA/PLGA-CAS, respectively. Subsequently, their material characteristics and biological effects were assessed. The incorporation of hydroxyapatite onto PLGA-CAS resulted in enhanced surface roughness and hydrophilicity, coupled with improved thermal stability and delayed degradation. Furthermore, μHA/PLGA-CAS induced osteogenic differentiation of osteoblast precursor cells, while nHA/PLGA-CAS improved endothelial cell adhesion and stimulated angiogenic differentiation in vitro. Collectively, these findings suggest that μHA/PLGA-CAS and nHA/PLGA-CAS, each with distinct characteristics, hold significant potential for application as microcarriers in various biomedical contexts.