Polyetheretherketone Double Functionalization with Bioactive Peptides Improves Human Osteoblast Response.

In recent years, the demand for orthopedic implants has surged due to increased life expectancy, necessitating the need for materials that better mimic the biomechanical properties of human bone. Traditional metal implants, despite their mechanical superiority and biocompatibility, often face challenges such as mismatched elastic modulus and ion release, leading to complications and implant failures. Polyetheretherketone (PEEK), a semi-crystalline polymer with an aromatic backbone, presents a promising alternative due to its adjustable elastic modulus and compatibility with bone tissue.

Neuroblastoma-derived hypoxic extracellular vesicles promote metastatic dissemination in a zebrafish model.

The zebrafish (Danio rerio) is a valuable model organism for studying human biology due to its easy genetic manipulation and small size. It is optically transparent and shares genetic similarities with humans, making it ideal for studying developmental processes, diseases, and drug screening via imaging-based approaches. Solid malignant tumors often contain hypoxic areas that stimulate the release of extracellular vesicles (EVs), lipid-bound structures released by cells into the extracellular space, that facilitate short- and long-range intercellular communication and metastatization.

Cohesive Zone Modeling of the Interface Fracture in Full-Thermoplastic Hybrid Composites for Lightweight Application.

With the increasing demand for lightweight and high-performance materials in the automotive and aerospace industries, full-thermoplastic hybrid composites have emerged as a pivotal solution, offering enhanced mechanical properties and design flexibility. This work aims to numerically model the fracture strength in full-thermoplastic hybrid composites made by forming and overmolding organosheets. The mode I fracture was investigated by modeling the behavior of T-joint specimens under a tensile test following the cohesive zone modeling (CZM) approach.

Physical, Mechanical, and Biological Properties of PMMA-Based Composite Bone Cement Containing Silver-Doped Bioactive and Antibacterial Glass Particles with Different Particles Sizes.

In the present work, antibacterial composite bone cement was designed by introducing a bioactive and antibacterial glass into a commercial formulation. The effect of glass particles' addition on the curing parameters of the polymeric matrix was evaluated; moreover, the influence of the glass particle size on the glass dispersion, compressive and bending strength, bioactivity, and antibacterial effect was estimated. The results evidence a delay in the polymerization kinetics of the composite cement, which nevertheless complies with the requirements of the ISO standard.

Wetting Characteristics of Laser-Ablated Hierarchical Textures Replicated by Micro Injection Molding.

Texturing can be used to functionalize the surface of plastic parts and, in particular, to modify the interaction with fluids. Wetting functionalization can be used for microfluidics, medical devices, scaffolds, and more. In this research, hierarchical textures were generated on steel mold inserts using femtosecond laser ablation to transfer on plastic parts surface via injection molding.

Texturing Technologies for Plastics Injection Molding: A Review.

Texturing is an engineering technology that can be used to enable surface functionalization in the plastics injection molding industry. A texture is defined as the geometrical modification of the topography by addition of surface features that are characterized by a smaller scale than the overall surface dimensions. Texturing is added to products to create novel functionalities of plastic products and tools, which can be exploited to modify interactions with other materials in contact with the surface.

Improving Numerical Modeling Accuracy for Fiber Orientation and Mechanical Properties of Injection Molded Glass Fiber Reinforced Thermoplastics.

Local fiber alignment in fiber-reinforced thermoplastics is governed by complex flows during the molding process. As fiber-induced material anisotropy leads to non-homogeneous effective mechanical properties, accurate prediction of the final orientation state is critical for integrated structural simulations of these composites. In this work, a data-driven inverse modeling approach is proposed to improve the physics-based structural simulation of short glass fiber reinforced thermoplastics.

Editorial for the Special Issue on Advances in Micro and Nano Manufacturing: Process Modeling and Applications.

Micro- and nano-manufacturing technologies have been developed in research and industrial environments to support product miniaturization and the integration of new functionalities [...

Modeling the Adhesion Bonding Strength in Injection Overmolding of Polypropylene Parts.

In this work, the bonding strength of overmolded polypropylene is investigated and modeled. A T-joint specimen was designed to replicate the bonding between a base and an overmolded stem made of the same polymer: a previously molded plaque was used for the base, and the stem was directly overmolded. The effect of melt temperature, holding pressure, and localized heating was investigated following the design of experiments approach.

Functionalization of Plastic Parts by Replication of Variable Pitch Laser-Induced Periodic Surface Structures.

Surface functionalization of plastic parts has been studied and developed for several applications. However, demand for the development of reliable and profitable manufacturing strategies is still high. Here we develop and characterize a new process chain for the versatile and cost-effective production of sub-micron textured plastic parts using laser ablation.

Injection molded polymeric micropatterns for bone regeneration study.

An industrially feasible process for the fast mass-production of molded polymeric micro-patterned substrates is here presented. Microstructured polystyrene (PS) surfaces were obtained through micro injection molding (μIM) technique on directly patterned stamps realized with a new zirconia-based hybrid spin-on system able to withstand 300 cycles at 90 °C. The use of directly patterned stamps entails a great advantage on the overall manufacturing process as it allows a fast, flexible, and simple one-step process with respect to the use of milling, laser machining, electroforming techniques, or conventional lithographic processes for stamp fabrication.

Antibiotic-free composite bone cements with antibacterial and bioactive properties. A preliminary study.

Two bone cements (Palacos R® and Palacos LV®) based on polymethylmethacrylate (PMMA), clinically used in several cemented prosthetic devices, have been enriched with silver containing bioactive glass powders and compared with the plain commercial ones. The obtained composite cements have been subjected to a preliminary characterization by means of morphological and compositional analyses, compression mechanical tests, bioactivity test (by soaking into simulated body fluids), leaching tests and in vitro antibacterial test (count of colonies forming units, McFarland index evaluation, inhibition zone evaluation). The glass powders appeared uniformly dispersed inside the PMMA matrix and good mechanical properties (in compression) have been reached.