Research provides results on the preparation of calcium phosphate coatings using plasma electrolytic oxidation. Calcium phosphate coatings are applied to titanium substrates measuring 20 x 30 x 2 mm. These substrates are produced using selective laser melting (SLM). Most implants are made of titanium and its alloys because of their excellent biocompatibility. However, they have disadvantages, including limited biological activity, wear, and corrosion resistance. Thus, to investigate the impact of the PEO method and the voltage on the coating characteristics, three different voltages, 200, 250, and 300 V, were used. This study utilized a JSM-6390LV scanning electron microscope (SEM) with an INCA Energy Penta FET X3 system. X-ray diffraction analysis was performed using a PANalytical X'Pert PRO diffractometer. Friction and wear tests were performed with a "ball–disk" setup on a TRB³ tribometer. The surface morphology shows that an increase in applied voltage leads to an increase in the size of the pores. At an applied voltage of 300 V, the PEO coating layer cracked and the surface became uncommonly rough. An elemental analysis of the sample cross-sections reveals the formation of TiO₂ layers enriched with Ca and P at voltages between 200 and 250 V. At 300 V, calcium phosphate layers are observed predominantly on the outer surface. XRD analysis shows the presence of hydroxyapatite and titanium oxide phases. The coefficient of friction and the wear rate largely depend on the morphology, pore size, and density of a layer of the titanium dioxide. Therefore, the sample at 250 V exhibits better wear resistance compared to the other two coated samples. The PEO method shows promise for manufacturing implants with calcium phosphate coatings for traumatology and orthopedics. Titanium implants with these coatings are expected to enhance osseointegration and reduce the risk of implant failure.

Trauma, cancer, infections, and degenerative and inflammatory diseases are all contributing to an increase in the prevalence of bone problems and deformities. Bone repair and replacement options are evolving as a result of advances in orthopedic technology and high-quality biomaterials. Biomaterials based on polymer scaffolds, such as chitosan, are making a substantial contribution to the rapid expansion of bone tissue engineering. New additives are constantly being developed in response to the rising need for increased bioactivity in biocomposites used for bone regeneration.

Here, we present the design and synthesis of a multifunctional, synthetic bioactive peptide composed of a fragment of human Cystatin C (CystC) and anoplin. By combining these two bioactive proteins, we aim to combine pro-regenerative and anti-inflammatory capabilities with antibacterial properties to effectively assist bone regeneration and wound healing while also preventing or treating bacterial infections throughout the healing process. The biological activity of the ug46 peptide and the chitosan-ug46 (CH-ug46) biocomposite was examined in vitro, and the results suggest improved regenerative properties of the CH-ug46 biocomposite, which is dose-dependent. Furthermore, while the ug46 peptide demonstrated limited antibacterial activity at low doses, the antibacterial capabilities of the biocomposites releasing high doses of peptide were able to suppress the growth of the selected bacteria strains that are commonly found infecting healed wounds.

Our findings indicate that synthetic peptides can be utilized to provide specific activities required to promote regeneration processes and prevent negative effects frequently associated with wound healing, such as microbiological infections or severe inflammation. Designed bioactive peptides show promise as additions to enhance porous scaffolds and may help to advance the development of specialized, custom-tailored biocomposites.

Over the past few decades, there has been significant progress in the field of biomaterials, specifically in addressing the challenges associated with tissue regeneration. By selecting the appropriate biomaterials and fabrication techniques, one can achieve tissue-specific architectures and structural properties for scaffolds. These scaffolds have also been modified with site-specific functionalities to facilitate optimal tissue regeneration. Despite these advancements, challenges like large-sized defects and infection-prone implant sites hinder the success of these scaffolds. To address these challenges, a highly porous poly (ɛ-caprolactone) (PCL) scaffold was developed utilizing high-internal-phase emulsion (HIPE, dispersed phase volume >74%) templating, which was further functionalized to impart antimicrobial properties. A single-step methodology was employed to create nanocomposite scaffolds made of crosslinked PCL. This was achieved by the polymerization of Pickering HIPEs of ɛ-caprolactone (CL) that were stabilized using hydrophobic silica nanoparticles (mSiNPs) at low concentrations. The developed scaffolds demonstrated cyclic compressional stability for multiple cycles. Further, the PCL nanocomposite scaffolds were functionalized using an antimicrobial therapeutic agent that could effectively prohibit the growth and formation of biofilm in the case of both S. aureus and E. coli. The developed nanocomposite scaffolds had no adverse effect on MG-63 cells, allowing their growth and surface adherence. The developed antimicrobial scaffolds of PCL demonstrated promising capability to not only allow regeneration at large defect sites but also avoidpossible implant-site infections.

Background: Bone Replacement is suggested for a patient when the patient's knee/limb bone region starts to be painful / swollen around the joint part due to osteoarthritis and other bone-related diseases; during surgery, a new bone implant made of metal on metal (titanium, cobalt-chromium) or a polymer on metal (polyethylene on titanium) is used. A huge disadvantage of this kind of bone implant is that it causes inflammation and infections due to the metal or polymer debris generated on the implant. Infections or inflammation caused by bacterium adherence to an implant surface, a biofilm formation occurring at the implantation site, and infections caused by metal debris generated from friction and movement of the knee joint are referred to as implant-associated infections.

Method: So, in this research work, we have developed a bio-ceramic-based composite coating on a metal implant comprising beta-Tricalcium phosphate, pectin, gelatin, and (PVP) polyvinylpyrrolidone on a titanium screw to increase biocompatibility, antibacterial activities, and anti-inflammatory activities of the implant. Composite coating on a bone implant will enhance cell growth around the implant and it gives a viable environment for the implanted site.

Results: The primary characterization of the composite coating materials is conducted by (SEM) Scanning Electron Microscopy with (EDX) Energy Dispersive X-ray, a (FTIR) Fourier Infrared Spectroscopy analysis, in vitro antibacterial testing, and anti-inflammatory testing and the in vitro degradation study is conducted for the determination of stability of the coating.

Conclusion: In the above tests, it is concluded that our novel composite coating materials have an increased antibacterial effect and biocompatibility in nature. However, further research is needed for the in vivo testing process to confirm the use of synthesized bio-ceramic-based composite coating for bone tissue engineering or bone defects.

Bone diseases are still a great concern among patients. Researchers are looking for a material for bone implants that meets all requirements and stimulates cells to grow rapidly. There are various possibilities for the consolidation of ceramic–metal alloys. In the present study, sintering under high vacuums was undertaken. The materials consist of a titanium alloy (Ti6Al4V), which is of course responsible for the strength, and a bioactivity-stimulating agent, hydroxyapatite, so that the bone cells are stimulated to proliferate and form new apatite layers.

The aim of this study was to determine sintering process parameters for titanium alloy and hydroxyapatite composite materials. The obtained matrices were sintered in a vacuum furnace. The materials were subjected to various tests to confirm the correctness of the selected values. Characterization was carried out using various test methods, including XRF, SEM, and microhardness testing. The results so far for the materials obtained show promising potential in the biomedical field. The choice of components and the methods of combining them were appropriate, which prevented the degradation of the samples.

The authors gratefully acknowledge financial support for the project “New Generation of Bioactive Laser Textured Ti/Hap Implants” under the acronym “BiLaTex” carried out within the M-ERA.NET 3 Call 2022 programme in the National Centre for Research and Development (ERA.NET3/2022/48/BiLaTex/2023).

Within the biomedical field, alternatives to natural bone are essential for repairing significant bone breaks that require rebuilding. Injectible, self-hardening bone cements like magnesium phosphate (MPC) are integral to orthopedic operations with minimal invasiveness. These biomaterials are valued for their biodegradable qualities, quick setting, and good mechanical strength, equating them with traditional bone substitutes such as calcium phosphates. However, there is a noted deficiency in the cohesion and ease of injection of MPC paste. This research delves into creating a novel functional biocement based on MPC enhanced with a poly(vinyl alcohol) (PVA) hydrogel to improve its application.
This biocomposite cement results from combining magnesium oxide with potassium dihydrogen phosphate in a PVA-based matrix. The study examines hydrogel’s impact by varying its concentrations and different content of cross-linking agent. The evaluation encompasses assessments of setting time and temperature, microstructural examination, identification of phases and chemical composition, static strength testing, injectability potential, and a cytocompatibility evaluation with human osteoblasts.
This research has culminated in the creation of a unique dual-setting bone cement, which merges magnesium phosphate cement with poly(vinyl alcohol) hydrogel. This novel biocomposite is characterized by exceptional attributes such as superior biocompatibility, proper biodegradation and improved functional qualities, reducing negative physiological responses and enhancing safety for clinical use. Furthermore, the material demonstrates
a reduced setting temperature, good porosity and enhanced injectability - allowing for more precise and minimally invasive surgical procedures. Consequently, this innovative biocement holds great potential for advancing orthopedic and trauma treatments.

Acknowledgments
This research was supported by the Gdańsk University of Technology by the DEC-3/2022/IDUB /III.4.3/Pu grant under the PLUTONIUM 'Excellence Initiative – Research University program.

Currently, there is an increasing discussion on the topic of the aging population and the associated problems. As the issue becomes more pressing, there is a rising need for surgical implants that meet specific requirements. Metal-based implants are being phased out due to their tendency to cause abnormal tissue growth. A more effective solution is to combine metal with ceramics, particularly hydroxyapatite, which has a structure similar to natural bone and can facilitate tissue regeneration. Surgical implants are designed to serve as bone replacements for as long as possible. The ideal implant should be characterized by its ability to integrate with the bone through osteointegration, mitigate inflammation, and promote bone regeneration.

In order to improve the durability and biocompatibility of a bone implant, a composite material based on the titanium alloy Ti6Al4V and hydroxyapatite can be designed. The process of obtaining the Ti-HAp composite involves several important elements, including the synthesis of hydroxyapatite particles with a specific morphology, 3D binder ket printing, and the sintering of materials.

Binder jetting is a 3D printing technology used for producing biomaterials. It allows for the production of components designed in a computer-aided design program, such as CAD. The binder jet method has several advantages, including the ability to produce multiple components in a single process and achieve high porosity for bone implants.

The binder jet 3D printing method can produce a composite biomaterial based on Ti6Al4V and HAp, which may serve as an alternative to conventional methods for obtaining bone implants. However, further research is necessary in order to improve production parameters and determine the final properties of Ti-HAp biocomposites.

This research was funded in whole by the National Science Centre, Poland, under the OPUS call in the Weave programme under registration number 2022/47/I/ST8/01778

Introduction: Composite materials are used in medicine for a wide range of practical tasks to improve human health. In traumatology and orthopedics, materials are used that combine biodegradable polymers with inorganic salts, most often calcium phosphates. Currently, the selection of multicomponent compositions of inorganic fillers that perform different functions and improve the characteristics of transplants is considered promising. In particular, the combination of phosphates and calcium silicates is of interest.

Methods: In this work, porous materials were made from powders containing synthetic hydroxyapatite (HA, Ca₁₀(PO₄)₆(OH)₂) and wollastonite (WT, β-CaCiO₃) in the ratios 0/100, 20/80, 40/60, 60/40, 80/20 and 100/0; chitosan gel (200 kDa, 90%); and carboxymethylcellulose. Granules were produced in various shapes—cylinders, spheres and hemispheres with a diameter of 4 mm. All samples were examined by XRD, FTIR, XPS, SEM and EDS analysis systems. The Vickers microhardness at HV0.2 load, the density and the porosity of the granules were studied. Their dissolution in tris-buffer, an isotonic solution, was studied. Their cytotoxicity was determined using the MTT test.

Results: The resulting materials are porous, rough and hydrophilic. The pore sizes are mainly 0.2–1.0 microns. The density of the samples ranges from 2.76 to 3.48 g/cm³, depending on the composition. The microhardness of the granules varies from 3.04 to 5.38 0.2HV. According to XRD and FTIR data, it was determined that no structural phase transitions of inorganic powders occur during the synthesis process. It was found that the highest rate of dissolution is observed in the tris-buffer, where samples of HA/W 60/40 degrade faster. It was determined that the granules do not have a cytotoxic effect.

Conclusions: Based on the results obtained, the new materials obtained are suitable for bone regeneration and can be studied in vivo.

INTRODUCTION. Understanding the hematological behavior of near-infrared (NIR) responsive plasmonic nanoparticles is crucial for their medical applications. Despite low concentrations, their nature may cause toxicity in biological environments through interactions with biomolecules. Especially interactions with plasma proteins have implications for hemostasis, thrombosis, and inflammatory responses. This study focuses on the interactions of isotropic and anisotropic silver nanoparticles (AgNPs) with bovine serum albumin (BSA) and their effects on red blood cells (RBCs)and clotting time.

METHOD. Specific localized resonant surface plasmon AgNPs were synthesized and exposed to protein. The protein solution was prepared within normal blood plasma limits (35-50 mg mL-1). UV-Vis and fluorescence spectroscopy were used to study the interaction, while transmission electron microscopy (TEM) was used to analyze changes in particle size and morphology. Fresh blood incubated with AgNPs was used to assess cell morphology changes. RBC content release, specifically lactate dehydrogenase (LDH) activity, was measured using UV–vis-NIRspectrophotometry to indicate membrane rupture. AgNPs' impact on blood coagulation times was investigated using a test kit after incubation.

RESULTS. UV-Vis was used to study the chemical environment of interface AgNPs/BSA. The results did not show changes in the prism-shaped particles at different concentrations, but the sphere-shaped particles showed decreased intensity. Fluorescence revealed that nanoparticles can induce the enhancement and quenching of protein emission, possibly due to conformational changes in the protein structure. By TEM, the aggregated state of the systems' AgNPs/BSA was confirmed. AgNPs showed minimal a impact on the RBC morphology and LDH release. The isotropic AgNPs increased LDH release compared to the anisotropic ones. Interaction with BSA may activate the coagulation cascade, but AgNPs showed no impact on coagulation time.

CONCLUSIONS. AgNPs interacted with BSA at lower than reported. Isotropic nanosilver distributes throughout the protein network, exerting reactivity. In addition to the effect on BSA organization, isotropic nanoparticles caused some RBCs disruption compared to the NIR-sensitive anisotropic AgNPs, which showed no negative effects on hemocompatibility. These results aid in developing devices loaded with NIR- light responsive nanosilver, ensuring safe use.

Introduction: magnesium alloys are promising for implants because of their biocompatibility and biodegradability. However, they are still poorly applied in clinics due to too rapid degradation, which does not match with tissue regeneration and is often associated with inflammation due to a pH rise and hydrogen development. The aim of this work is the development of natural organic coatings that can modulate the degradation rate of the substrates.

Methods: Plane samples (AZ31-AZ91) and porous 3D structures (AZ91) obtained by 3D printing combined with investment casting were considered as substrates. Natural organic coatings, tannic acid (TA) or polyphenols extracted from green tea leaves (TPH) were obtained by immersion in aqueous solutions of the selected molecules without the addition of toxic chemicals. The functionalization conditions were optimized in order to obtain homogeneous coatings that were free of cracks.

Results: Coating formation by soaking allowed for the treatment of complex geometries and porous structures. TA uniformly covered the surface of magnesium alloys, maintaining its redox activity after grafting, as well as the micro-topography, but it presented several micro-cracks (more evident in AZ31). The TA coating allowed us to keep the pH at the physiological level during AZ91 soaking in PBS. The result was less effective on AZ31. TA-coated AZ91 was poorly corroded after 14 days of soaking in PBS, and TA was still present on it. However, electrochemical tests did not evidence the effects of the coating improvements in terms of corrosion potential and rate. This effect was probably due to the presence of cracks. The use of TPH and surface pre-treatment allowed for the development of more homogeneous and crack-free coatings on both AZ91 and AZ31 surfaces. These coatings presented improved corrosion resistance (electrochemical tests) and biocompatibility.

Conclusion: Natural organic coatings represent a promising green and sustainable strategy for the modulation of the degradation rate of magnesium alloys for biomedical applications.