The growing need for durable implants, driven by aging populations and increased trauma cases, highlights challenges such as limited osseointegration and biofilm formation. 45S5 Bioglass® has shown promise due to its bioactivity, antimicrobial properties, and ability to enhance osseointegration through electrical polarization. This study investigates the effects of incorporating different concentrations of ZrO2 and Fe3O4 into 45S5 Bioglass® to enhance its electrical and biological properties. Raman analysis was used to evaluate how these oxides influenced the amount of non-bridging oxygens (NBOs) and glass network connectivity. Electrical characterization was performed using impedance spectroscopy to measure conductivity and ion mobility. Antibacterial activity was assessed using the agar diffusion method, and bioactivity was evaluated through simulated body fluid (SBF) immersion tests. The results revealed that bioglasses containing ZrO2 exhibited higher NBO content compared to Fe3O4, leading to improved electrical and biological properties. ZrO2, particularly at 2 mol%, significantly enhanced conductivity, antibacterial activity, and bioactivity. In contrast, Fe3O4 reduced both antibacterial activity and bioactivity. The findings demonstrate that ZrO2 addition improves the electrical and biological performance of 45S5 Bioglass®, making it a promising candidate for durable implants. Fe3O4, however, showed limited benefits.

This study investigates the effect of (Co + Al) co-doping on the physical properties of the ZnO nanoparticles, synthesized via the simple co-precipitation method. X-ray diffraction (XRD) analysis revealed a hexagonal structure for all samples, with a formation of Al2O3 phase in both Zn0.98Co0.01Al0.01O and Zn0.94Co0.01Al0.05O nanoparticles. The crystallite size increased from 26.5 nm for ZnO to 16.6 nm for Zn0.94Co0.01Al0.05O nanoparticles. Scanning electron microscopy (SEM) technique showed a notable alteration in the morphology of ZnO upon the incorporation of Al. A transition from spherical nanoparticles in ZnO and Co doped ZnO to irregular, dendritic-like structures in (Co + Al) co-doped nanoparticles is observed. Transmission electron microscopy (TEM) substantiated the presence of the Al2O3 phase in the co-doped samples. Raman and FTIR spectroscopy confirmed the incorporation of Co and Al into the ZnO lattice through the presence of Co-O-Co and Al-O bonds. Optical characterization indicated a decrease in the band gap energy from 3.18 eV in ZnO to 2.84 eV in Zn0.94Co0.01Al0.05O nanoparticles. Electrical conductivity measurements revealed an increase from 1.2 x 10(-4) Omega(-1) cm(-1) to 1.8 x 10(-3) Omega(-1) cm(-1) as the Al content increased from 0 % to 5 % at the frequency of 10(3) Hz and the temperature of 423K. Likewise, dielectric constant raised from 775 in ZnO to 5455 in Zn0.94Co0.01Al0.05O nanoparticles at the temperature 423K. These results highlight the potential of (Co + Al) co-doped ZnO nanoparticles for advanced optoelectronic applications.

Electrophoretic deposition is a straightforward, environmentally friendly, and cost-effective technique for depositing and synthesizing nanomaterials, particularly nanofilms of semiconductors. Key parameters in electrophoresis include deposition time and voltage. Zinc oxide, a semiconductor of significant interest in solar energy research, possesses favorable characteristics, notably, a band gap value of approximately 3.33 eV. In the realm of dye-sensitized solar cells, which represent the third generation of solar cells, zinc oxide has emerged as a compelling choice for a photoanode. This study focused on depositing thin films of zinc oxide through electrophoresis and applying them as photoanodes in dye solar cells. The results demonstrated that the electrodeposited films exhibited good reflectance in the visible spectrum (~60–90%), a band gap energy of 3.28 eV, and an incident photon conversion efficiency of approximately 4.48% for the electrodeposited film at 80 V for 5 min.

The aging population and increasing incidence of trauma among younger age groups have heightened the increasing demand for reliable implant materials. Effective implant materials must demonstrate rapid osseointegration and strong antibacterial properties to ensure optimal patient outcomes and decrease the chance of implant rejection. This study aims to enhance the bone–implant interface by utilizing 45S5 bioglass modified with various concentrations of Fe3O4 as a coating material. The effect of the insertion of Fe3O4 into the bioglass structure was studied using Raman spectroscopy which shows that with the increase in Fe3O4 concentration, new vibration bands associated with Fe-related structural units appeared within the sample. The bioactivity of the prepared glasses was evaluated using immersion tests in simulated body fluid, revealing the formation of a calcium phosphate-rich layer within 24 h on the samples, indicating their potential for enhanced tissue integration. However, the sample modified with 8 mol% of Fe3O4 showed low reactivity, developing a calcium phosphate-rich layer within 96 h. All the bioglasses showed antibacterial activity against the Gram-positive and Gram-negative bacteria. The modified bioglass did not present significant antibacterial properties compared to the bioglass base.

45S5 Bioglass has been widely used in regenerative medicine due to its ability to dissolve when inserted into the body. Its typically amorphous structure allows for an ideal dissolution rate for the formation of the hydroxyapatite layer, which is important for the development of new bone. This bioactive capacity can also be controlled by adding other oxides (e.g., SrO, ZnO, and MgO) to the 45S5 Bioglass network or by storing electrical charge. Ions such as zinc, magnesium, and strontium allow for specific biological responses to be added, such as antibacterial action and the ability to increase the rate of osteoblast proliferation. The charge storage capacity allows for a higher rate of bioactivity to be achieved, allowing for faster attachment to the host bone, decreasing the patient’s recovery time. Therefore, it is necessary to understand the variation in the structure of the bioglass with regard to the amount of non-bridging oxygens (NBOs), which is important for the bioactivity rate not to be compromised, and also its influence on the electrical behavior relevant to its potential as electrical charge storage. Thus, several bioactive glass compositions were synthesized based on the 45S5 Bioglass formulation with the addition of various concentrations (0.25, 0.5, 1, and 2, mol%) of zinc, strontium, or magnesium oxides. The influence of the insertion of these oxides on the network was evaluated by studying the amount of NBOs using Raman spectroscopy and their implication on the electrical behavior. Electrical characterization was performed in ac (alternating current) and dc (direct current) regimes.

Galactomannans are polysaccharides obtained from legume seed extraction. They present a chemical structure consisting of D-mannose chains linked by glycosidic bonds and galactose branches. The main focus lies in their use as thickeners in the food industry, aimed at improving the dielectric properties of food during heating processes within the radiofrequency and microwave ranges. In this work, the prepared galactomannan samples were electrically analyzed through impedance spectroscopy, which is a powerful physical technique. From the experimental measurements, the dielectric permittivity and loss tangent of the galactomannan solutions were analyzed and the electrical modulus formalism was used to study the dielectric relaxations. Crude galactomannans exhibited higher values of permittivity, conductivity, and losses compared to purified galactomannans. Increasing ethanol concentration in galactomannan purification causes an increase in the permittivity and conductivity of galactomannan solutions. In a 1% solution, at 1 kHz, the permittivity increased from 378.56 to 538.09, while in the 2% solution, this increase was from 656.22 to 1103.24. Regarding the conductivity, at the same frequency, the increase was from 1.6 × 10−3 to 3.3 × 10−3 Ω−1m−1 and from 2.9 × 10−3 to 5.5 × 10−3 Ω−1m−1, respectively. The rise of the ethanol concentration in galactomannan purification led to a decrease in the relaxation time, from 448.56 to 159.15 μs and from 224.81 to 89.50 μs in the solution with 1 and 2%, respectively. The results suggest that galactomannan from Adenanthera pavonina L. has potential for use in the food industry.

In recent decades, the requirements for implantable medical devices have increased, but the risks of implant rejection still exist. These issues are primarily associated with poor osseointegration, leading to biofilm formation on the implant surface. This study focuses on addressing these issues by developing a biomaterial for implant coatings. 45S5 bioglass® has been widely used in tissue engineering due to its ability to form a hydroxyapatite layer, ensuring a strong bond between the hard tissue and the bioglass. In this context, 45S5 bioglasses®, modified by the incorporation of different amounts of copper oxide, from 0 to 8 mol%, were synthesized by the melt–quenching technique. The incorporation of Cu ions did not show a significant change in the glass structure. Since the bioglass exhibited the capacity for being polarized, thereby promoting the osseointegration effectiveness, the electrical properties of the prepared samples were studied using the impedance spectroscopy method, in the frequency range of 102–106 Hz and temperature range of 200–400 K. The effects of CuO on charge transport mobility were investigated. Additionally, the bioactivity of the modified bioglasses was evaluated through immersion tests in simulated body fluid. The results revealed the initiation of a Ca–P-rich layer formation on the surface within 24 h, indicating the potential of the bioglasses to enhance the bone regeneration process.

This work investigates the dielectric properties of barium titanate/gadolinium ferrite ceramic composites, with different concentrations of each material. Our objective was to increase the storage ability of this material, finding a compromise between high permittivity and low dielectric losses. A two-step sintering procedure was used in the preparation of the composites to attain the desired results. Their morphological, structural and electrical properties were tested using scanning electron microscopy, X-Ray powder diffraction and impedance spectroscopy, respectively. Dielectric characterizations were performed on the frequency band of 100 Hz-1 MHz and for different temperatures (180-380 K). The best compromise between barium titanate and gadolinium ferrite in the composition was calculated in order to obtain a potential material for electrical energy storage. The sample with 25% gadolinium ferrite presented the best results. The dielectric constant reached values of the order of 2000, at 1 kHz and 340 K. It was also important not to have very high losses, and this was confirmed by the calculated loss tangent.

Bone replacement is one of the major medical procedures in the oral surgery field due to the progressive ageing population and to illness or trauma in younger age groups. The use of implants without biological activity and effective osseointegration increases the chances of implant failure. This work aims to improve the interaction between implants and bone by using Bioglass 45S5 (BG)/hydroxyapatite (HAp) mixtures, including copper-, zinc-, and cerium-doped BG, as well as co-doping by the mentioned metals, as coatings produced by the CoBlast (TM) technique. All coatings present a uniform coverage of the Ti-6Al-4V substrate. Furthermore, in vitro testing using human osteosarcoma Saos-2 cells indicated that BG/HAp coatings have no cytotoxic effect, and the used of doping agents did not alter cell adhesion, proliferation, or alkaline phosphatase (ALP) expression when compared to undoped coating. These results demonstrate that BG/HAp by CoBlast (TM) can be a solution to improve implants' osseointegration.

Dental implants have emerged as one of the most consistent and predictable treatments in the oral surgery field. However, the placement of the implant is sometimes associated with bacterial infection leading to its loss. In this work, we intend to solve this problem through the development of a biomaterial for implant coatings based on 45S5 Bioglass® modified with different amounts of niobium pentoxide (Nb2O5). The structural feature of the glasses, assessed by XRD and FTIR, did not change in spite of Nb2O5 incorporation. The Raman spectra reveal the Nb2O5 incorporation related to the appearance of NbO4 and NbO6 structural units. Since the electrical characteristics of these biomaterials influence their osseointegration ability, AC and DC electrical conductivity were studied by impedance spectroscopy, in the frequency range of 102–106 Hz and temperature range of 200–400 K. The cytotoxicity of glasses was evaluated using the osteosarcoma Saos-2 cells line. The in vitro bioactivity studies and the antibacterial tests against Gram-positive and Gram-negative bacteria revealed that the samples loaded with 2 mol% Nb2O5 had the highest bioactivity and greatest antibacterial effect. Overall, the results showed that the modified 45S5 bioactive glasses can be used as an antibacterial coating material for implants, with high bioactivity, being also non-cytotoxic to mammalian cells.

Biofilm-related implant infections pose a substantial threat to patients, leading to inflammation in the surrounding tissue, and often resulting in implant loss and the necessity for additional surgeries. Overcoming this implantology challenge is crucial to ensure the success and durability of implants. This study shows the development of antibacterial materials for implant coatings by incorporating copper into 45S5 Bioglass®. By combining the regenerative properties of Bioglass® with the antimicrobial effects of copper, this material has the potential to prevent infections, enhance osseointegration and improve the long-term success of implants. Bioglasses modified with various concentrations of CuO (from 0 to 8 mol%) were prepared with the melt-quenching technique. Structural analysis using Raman and FTIR spectroscopies did not reveal significant alterations in the bioglasses structure with the addition of Cu. The antibacterial activity of the samples was assessed against Gram-positive and Gram-negative bacteria, and the results demonstrated significant inhibition of bacterial growth for the bioglass with 0.5 mol% of CuO. Cell viability studies indicated that the samples modified with up to 4 mol% of CuO maintained good cytocompatibility with the Saos-2 cell line at extract concentrations up to 25 mg/mL. Furthermore, the bioactivity assessment demonstrated the formation of a calcium phosphate (CaP)-rich layer on the surfaces of all bioglasses within 24 h. Our findings show that the inclusion of copper in the bioglass offers a significant enhancement in its potential as a coating material for implants, resulting in notable advancements in both antibacterial efficacy and osteointegration properties.

Implantology is crucial for restoring aesthetics and masticatory function in oral rehabilitation. Despite its advantages, certain issues, such as bacterial infection, may still arise that hinder osseointegration and result in implant rejection. This work aims to address these challenges by developing a biomaterial for dental implant coating based on 45S5 Bioglass® modified by zirconium insertion. The structural characterization of the glasses, by XRD, showed that the introduction of zirconium in the Bioglass network at a concentration higher than 2 mol% promotes phase separation, with crystal phase formation. Impedance spectroscopy was used, in the frequency range of 102–106 Hz and the temperature range of 200–400 K, to investigate the electrical properties of these Bioglasses, due to their ability to store electrical charges and therefore enhance the osseointegration capacity. The electrical study showed that the presence of crystal phases, in the glass ceramic with 8 mol% of zirconium, led to a significant increase in conductivity. In terms of biological properties, the Bioglasses exhibited an antibacterial effect against Gram-positive and Gram-negative bacteria and did not show cytotoxicity for the Saos-2 cell line at extract concentrations up to 25 mg/mL. Furthermore, the results of the bioactivity test revealed that within 24 h, a CaP-rich layer began to form on the surface of all the samples. According to our results, the incorporation of 2 mol% of ZrO2 into the Bioglass significantly improves its potential as a coating material for dental implants, enhancing both its antibacterial and osteointegration properties.

Simulated Body Fluid (SBF) for biomedical research, containing several types of ions, is dielectrically characterized by the impedance spectroscopy technique. The real and imaginary parts of the electrical admittance of the SBF are determined by several concentrations of ions dissolved in it. The time dependence of the volume dielectric parameters of the SBF with the frequency indicates an exponential behavior and it is practically independent of the hydroxyapatite (HAp) immersed in it. On the other hand, the surface dielectric parameters show significant differences when the hydroxyapatite was present. Qualitatively, related to chemical kinetic and using the integrated rate law, it was possible to find the half-life time.

This work aims to develop a biomaterial for implants with superior antibacterial function, better angiogenesis and rapid osteointegration. For this purpose, 45S5 bioglasses modified by adding different amount of iron oxide (Fe 3 O 4 ), from 0 to 8 mol%, were prepared by melt-quenching technique. The structure of the prepared glasses studied by XRD and FTIR showed that the insertion of Fe 3 O 4 do not induce significant changes and thus not affect the beneficial characteristics of the bioglass. Since the electrically polarized bioactive glass and ceramics have been demonstrated to enhance their osteoconductivities, the AC and DC electrical conductivity have been investigated using impedance spectroscopy in the frequency range from 10 2 to 10 6 Hz and over the temperature range, 200–400 K. The effects of iron loading on the charge transport mobility were studied. The biocompatibility of the glasses was evaluated in vitro by cell-biomaterial interaction test which show that the glasses are viable for biomedical applications.

A series of polyvinyl acetate polymer matrices (PVAc) incorporated with two different TEMPO-oxidized cellulose nanofibrils (CNF with 5 min and 2 h of oxidation) were studied. These composites have proven to be suitable for use as ion battery separators. For this purpose, dielectric properties and electrical conductivity have been investigated using impedance spectroscopy in the frequency range from 102 to 106 Hz and over the temperature range, 200–350 K. The effects of CNF loading on the molecular motion and the charge transport mobility in PVAc polymer chains were studied. Calculation of the strength parameter for the α-relaxation process revealed a threshold value of 8 % in the volume fraction of filler. A comparative study of the two nanocomposites films showed that PVAc/CNF-5 min nanocomposites were able to build a denser CNF network and hence the highest potential of filling effect than those of PVAc/CNF-2 h films. According to our results, the volume fraction of 8 % of CNF-5 min is recommended for achieving the highest performing nanocomposite with potential applications.

The advantages of implants are notorious, from both functional and aesthetic points of view. Their fixed nature contributes positively to a significant increase in the patient's self-confidence and in the well-being by promoting a healthy lifestyle. This work intends to develop a biomaterial for implants, with superior osteointegration capacity. For this purpose, 45S5 bioactive glass doped with copper (Cu) that significantly enhances angiogenesis and presents antibacterial activity, were prepared and analyzed physically, chemically, and biologically. The incorporation of Cu ions does not show a significant change in the glass structure and does not alter the desirable properties of the bioactive glass. Impedance spectroscopy has been used to study the AC and DC electrical conductivity across the temperature range of 200–400 K and in the frequency range of 10 2 –10 6 Hz. The effects of copper on charge transport mobility were investigated. The in vitro biocompatibility was assessed by means of cytotoxicity tests. The results show that the glasses loaded with up to 4% of Cu are non-toxic to the tested cells.

In this work, the influence of the incorporation of nanoparticles (organo-modified montmorillonite Cloisite 30B) in polyamide 6 (PA6) on rigid amorphous fraction (RAF) formation had been explored employing Differential Scanning Calorimetry (DSC), Flash Differential Scanning Calorimetry (Flash DSC) and Broadband Dielectric Spectroscopy (BDS) techniques. The existence of a RAF in PA6-montmorillonite nanocomposite films is available from specific heat capacity measurement at the glass transition region of the nanocomposites. It was shown that at high C3OB content, this fraction becomes larger. Using Flash DSC, it was possible not only to measure the heat capacity step at the glass transition of the materials, but also to provide quantitative knowledge on the kinetics of crystallization and nucleation of PA6-based nanocomposites. The dielectric relaxation spectroscopy measurement was investigated, in the frequency range 0.1-10(6) Hz and varying temperature from 20 to 200 degrees C, which highlight different relaxation phenomena: the alpha dipolar relaxation, the alpha c relaxation and Max-well-Wagner-Sillars (MWS) interfacial polarizations. As C30B content increases, a MWS relaxation emerges in the nanocomposites, thus revealing the increase of RAF in the nanocomposite with high C30B content.

In this work, the dielectric properties and the electrical conductivity of polyvinyl acetate (PVAc) polymer doped with cellulose nanocrystals (CNC), extracted from the date palm rachis, are reported. We investigate the filler effect on the molecular mobility of the PVAc polymer chains and the charge transport properties of this material. PVAc/CNC films structure was characterized by powder X-Ray diffraction (XRD), showing the crystalline behavior of the cellulose filler. The dielectric properties were investigated using impedance spectroscopy, in the frequency range of 102-106 Hz and temperatures from 200 to 350 K. A beta relaxation, assigned to the motions of the -OCOCH3 side groups, and alpha relaxation, associated with the glass transition of the PVAc matrix, can be detected.