Papers by Keyword: Antibacterial

Abstract: This study aims to evaluate the antibacterial properties of dental resin photopolymer (DRP) specimens modified with additive titanium dioxide (TiO₂) nanoparticles using stereolithography 3D printing technology. TiO₂ known for its excellent biocompatibility, making it a promising additive for enhancing bacterial resistance. Specimens were fabricated with varying compositions of TiO₂ and characterized for surface morphology using Scanning Electron Microscopy (SEM). Antibacterial activity was assessed against Staphylococcus aureus (Gram-positive) and Escherichia coli (Gram-negative) using Kirby-Bauer disc diffusion method. SEM analysis revealed that TiO₂ particles were relatively well-dispersed on the matrix surface. Antibacterial testing showed the formation of inhibition zones, particularly in sample with composition 5%wt TiO₂, indicating increasing antibacterial performance. The activity was more pronounced against S. aureus, attributed to its less complex cell wall structure and more susceptible to reactive oxygen species (ROS) generated by TiO₂ photocatalytic conditions. These findings suggest that TiO₂-modified DRP has strong potential as an antimicrobial dental restorative material fabricated through SLA-based 3D printing.

Abstract: Abstract. In this work, ZnO nanoparticles (NPs) were prepared using Thymus vulgaris extract and modified through copper doping and copper–lanthanum co-doping. Structural analyses (XRD, Raman, FTIR, SEM) confirmed the wurtzite crystal phase with polyhedral morphology across all samples. Distinct performance trends were observed depending on the doping strategy. Cu–ZnO demonstrated the highest insecticidal efficacy against Myzus persicae, achieving complete mortality within four days, and exhibited superior photocatalytic activity, removing 86.3% of methylene blue within one hour under visible light. In contrast, Cu–La–ZnO displayed enhanced antibacterial performance, producing the largest inhibition zones against Staphylococcus aureus (17 mm), Escherichia coli (15 mm), and Salmonella typhimurium (16 mm). These findings suggest that copper doping predominantly promotes reactive oxygen species generation, favoring insecticidal and photocatalytic functions, while the synergistic incorporation of lanthanum enhances antibacterial interactions.

Abstract: The increasing demand for effective ocular prosthetics has led to the exploration of innovative materials for orbital implants. The study focuses on the preliminary biocompatibility assessment of nanozinc bioceramic orbital implant intended for anophthalmic socket applications. These implants aim to address common complications such as infection and inflammation in patients requiring ocular prostheses. Bioceramic orbital implants were fabricated using conventional techniques using biphasic calcium phosphates and kaolin clay as raw materials. The bioceramic material, engineered for its antibacterial properties, is evaluated for its cytotoxic response. In vitro tests are conducted to determine the cellular response and antibacterial efficacy of the implants. Effect of different loadings of nanozinc oxide onto the bioceramic orbital implant were investigated. Disc diffusion method using test organisms Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) has revealed the resistance of the bioceramic orbital implant against bacterial attack. Moreover, MTT cytotoxicity test has shown fibroblast cell viability indicating good biocompatibility. Ultimately, the bioceramic orbital implant has presented no adverse effects upon exposure to Albino rabbits using dermal and eye irritation tests. The findings from this preliminary research will provide crucial insights into the feasibility and safety of using antibacterial bioceramic materials for orbital implants, potentially improving clinical outcomes for patients with anophthalmic sockets.

Abstract: Advanced biocompatible piezoelectric composites have gained significant attention for the development of flexible medical devices and especially related to materials structures that mimic the natural tissue structures. Natural piezoelectricity within the human tissues is reviewed, together with nature-based piezoelectric materials, their advantages and potential for designing the structures for biomedical applications. Electrospun Polyvinylidene fluoride (PVDF) nanofiber matrix, reinforced with silver nanoparticles (AgNPs) is discussed, including specific applications in bone grafts, biosensors and energy harvesting. Processing parameters of the electrospinning fabrication technology have a strong influence on the composite piezoelectricity. Computational models of piezoelectric composites have become a major support in material design for the real case applications. Existing approaches to the numerical modeling of piezoelectric composites have been shortly reviewed toward a recent trend of AI supported modeling for providing effective composite properties, prediction and optimization of material properties and behavior, such as the output voltage and power. Polymer-based biomedical piezoelectric composites have shown excellent results in laboratory research from aspects of their flexibility and possibility to tailor their electro-mechanical properties. However, output piezoelectric signals are still much lower than in the case of traditional ceramic-based materials, including challenges related to the stability of the electric signal, signal noise, piezoelectric impedance and durability of composites with nature-based reinforcements. Future directions in custom composite design, including currently available computational models to enable more rapid development of biomedical piezoelectrics are elaborated at the end.

Abstract: Silver nanoparticles (AgNPs) are very useful in biomedical applications, especially for the development of anti-infection implants. For biomedical applications, AgNPs that were fabricated by green synthesis approach are more favorable than conventional approach using toxic reducing agent such as NaBH₄ or N₂H₄. In this study, AgNPs were prepared through green synthesis approach using extract of Seminyak leaves and pH were varied (5; 8 and 11) to know the influence of pH on formation of AgNPs. Visual observations reveal that increasing pH led to faster color change of samples (yellow to black) suggesting that pH is directly proportional to reaction kinetics. UV-Vis spectroscopy results unveil that strong peak at 422 nm was observed in sample with pH 11, while low and broad peak were observed in sample with pH 5 and 8, implying the presence of nano-sized particles in sample with pH 11 and larger particles in sample with pH 5 and 8. Transmission electron microscopy (TEM) characterization results shows that dispersion of nano-sized particles with particle size 15.4 ± 4.1 nm were observed in sample with pH 11, while aggregation of nano-sized particles with particle size 29.2 ± 7.2 nm and 20.8 ± 7.0 nm were observed in sample with pH 5 and 8 respectively. X-ray diffraction (XRD) results show that the intensity of Ag’s peak in sample with pH 11 is at least two times higher than other samples, indicating formation of AgNPs in sample with pH 11 is more favorable than other samples. The results suggest that formation of dispersed and uniform AgNPs in the presence of extract of seminyak leaf as capping and reducing agent were favorable at high pH conditions.

Abstract: Mineral trioxide aggregate (MTA) is a common biomaterial used for endodontic treatment. However, this material does not have antibacterial activity, and the addition of an antibacterial agent is necessary. In this research, CuO nanoparticles (CuONP) have been added to MTA to improve the compressive strength and antibacterial activity. CuONP was synthesized by mixing 25 mL CuSO₄.5H₂O 0.5 M and Na₂CO₃ 0.5 M at volume variations (15, 25, and 42 mL), sonicating the mixture at a temperature of 60 °C for 2 hours, and calcining at a temperature of 600 °C for 4 hours. MTA/CuO material was made by mixing MTA and CuONP at variations in weight percentage (1, 2, and 3%). CuONP, MTA, and MTA/CuO were characterized with Fourier Transform Infrared (FT-IR), X-ray diffractometer (XRD), and Scanning Electron Microscopy-Energy Dispersive X-ray (SEM-EDX). The compressive strength and antibacterial properties against Staphylococcus aureus and Pseudomonas aeruginosa were also tested. The results showed that CuONP was successfully synthesized with an average particle size of 21.94 nm. Adding CuONP 2% to MTA improved its compressive strength of 12.03±0.44 MPa. In addition, the presence of CuONP in the MTA gave the antibacterial property of S. aureus with an inhibition zone value of 6.69±0.67 mm for MTA/CuO-2 and 6.77±0.31 mm for MTA added with 3% of CuONP. However, adding CuONP did not increase significant antibacterial activity against P. Aeruginosa. Adding CuONP 3% increased the inhibition zone from 5.50±00 to 7.04±0.39 mm. The findings indicated that MTA modified with CuONP can potentially be applied for endodontic treatment even though further investigation is still necessary to test the biocompatibility and cytotoxicity.

Abstract: Magnetite nanoparticles are synthesized in an environmentally friendly way by utilizing natural ingredients found in citrus limon juice. The acid in citrus limon juice serves as a fuel for the sol-gel process, producing magnetite nanoparticles. Annealing treatment (400°C, 500°C, and 600°C) is used to change the structural and magnetic properties of the magnetite nanoparticles. All samples magnetite phase was verified by X-Ray Diffraction (XRD) examination. Increasing the annealing temperature causes an increase in crystallite size from 10.81 to 27.30 nm. Furthermore, the results of infrared spectroscopy revealed the presence of oxide bonds (M-O) in the range 558–567 cm^-1 and 408–437 cm^-1, which are Fe-O bonds. Magnetic properties also change as a result of the annealing treatment, which is characterized by increased saturation magnetization and changes in other magnetic parameters. Furthermore, green synthesis of magnetite nanoparticles is effective against gram-negative bacteria (E. Coli) with enhanced antibacterial performance.

Abstract: Inherent magnetic features of engineered nanoparticles are quite important parameters for biomedical application. In this study, trying to process Bengawan Solo iron sand into a material that has potential for cobalt ferrite (CFO-NPs) and silver-cobalt ferrite (AgCFO-NPs) were synthesized by aqueous extract of tumeric. To modify the physical properties, annealing treatment was carried out at non-annealing temperatures and 500°C. The characterized by various instrument, and utilized for biomedical application with antibacterial activity. These are characterized XRD with showing results particle size was calculated by the Scherrer formula, which is around 19 nm to 25 nm. The results of FTIR peak adsorption at 400 and 600 cm^-1 it shows the characteristics of spinel ferrite and the presence of vibrations at tetrahedral and octahedral sites. The coerciveness field (Hc) while those subjected to annealing temperature treatment increased from 46 Oe to 136 Oe. Nanoparticles cobalt ferrite (CFO-NPs) and silver-cobalt ferrite (AgCFO-NPs) can be used as antibacterial application. The AgCFO-NPs material has an antibacterial function as seen in the antibacterial test. AgCFO-NPs showed a good response being able to inhibit the growth of Staphylococcus aureus and Eschericia coli bacteria. By the obtained result it can be claimed that material nanoparticles will be useful model for biomedical applications if they are explored at advance level.

Abstract: The Silver-graphene oxide (AgGO) nanocomposite is highly regarded for controlling the biological activity of silver nanoparticles (AgNPs). Combining AgNPs with Graphene Oxide (GO) offers better stability than single AgNPs. Traditional chemical synthesis methods use toxic reducing agents, posing environmental risks. This study aims to synthesize AgGO nanocomposite using a green synthesis method with chives (Allium tuberosum) extract as a reducing and stabilizing agent. The reducing properties of chives extract are attributed to its sulfur-containing compounds play a crucial role in the reduction of silver ions to silver nanoparticles. AgGO nanocomposite was synthesized with different chives extract concentrations (0.5 M, 1.1 M, and 2.0 M) and confirmed using UV-Visible spectrometer, X-Ray Diffraction (XRD), and High-resolution transmission electron microscopy (HRTEM). The 1.1 M concentration was the most efficient, forming AgNPs at 430 nm with an average particle size of 18 nm. The antibacterial activity against E. coli and S. aureus was assessed, revealing that AgGO-1.1 has significant antibacterial capabilities comparable to pure AgNPs.

Abstract: This study proposed to synthesize the silver nanoparticle/kappa carrageenan-chitosan (AgNPs/KCar-Chit) hydrogel films and identify the effects of AgNPs on their physical properties and antibacterial performance. The AgNPs/KCar-Chit has been synthesized in 2 stages. The first stage was the synthesis of AgNPs/KCar colloids via the chemical reduction route assisted by microwave irradiation. In the second stage, the silver/kappa carrageenan (AgNPs/KCar) colloid was incorporated with chitosan, and a film was made using the casting technique. The silver nanoparticles formed were validated with a UV-Vis spectrophotometer through the absorption peak at about 400 nm wavelength. FTIR spectra exhibited peaks emerging at the wavenumber 1559.89 cm^-1 – 1561.75 cm^-1, indicating the formation of the carrageenan-chitosan polyelectrolyte complex. The AgNPs/KCar-Chit hydrogel films had an average solubility of 32%-34%, swelling of 300%-304%, and the surface morphology formed aggregates. The mechanical properties were particularly affected by the incorporation of chitosan. Still, the introduction of AgNPs into the films also influenced the tensile strength, elongation, and elasticity of the AgNPs/KCar-Chit hydrogel film. Further, the greater concentration of AgNPs enhanced the antibacterial performance of the AgNPs/KCar-Chit hydrogel films.