In this research study, various nanocomposites, namely Dy2O3, Sm2O3, HAP/Dy2O3, HAP/Dy2O3/GO, and HAP/Sm2O3/GO, were extensively examined and analyzed. The primary focus was on the development of ...advanced biomaterials with improved mechanical properties, biocompatibility, and antimicrobial activity. The investigation involved the use of transmission electron microscopy (TEM) and scanning electron microscopy (SEM) techniques to observe the distinctive nanorods of hydroxyapatite (HAP) within the ternary nanocomposite. The SEM micrographs yielded an average size of 69 ± 22 * 19 ± 4 nm for the HAP nanorods, accompanied by an average roughness measurement of 10.5 nm. The TEM analysis provided further insights into the distribution of HAP and Sm2O3 within graphene oxide (GO) nanosheets, revealing HAP particles measuring 20 nm in size and 65 nm in length, and Sm2O3 particles measuring 6 nm in size. To evaluate the biocompatibility of the newly developed ternary nanocomposite, HAP/Dy2O3/GO, osteoblast cells were employed. The results showed a minor decrease in cell viability, with a measured percentage of cell viability at 97.5 ± 2.1 %. Furthermore, the HAP/Dy2O3/GO nanocomposite exhibited notable antibacterial properties against E. coli and S. aureus bacteria, as indicated by inhibition zones measuring 15.3 ± 0.8 mm and 15.9 ± 1.1 mm, respectively. The unique composition of HAP/Dy2O3/GO demonstrated enhanced roughness parameters and improved biocompatibility due to its altered topological features. Additionally, its remarkable antibacterial activity and robust mechanical strength establish HAP/Dy2O3/GO as a promising candidate for further investigation as a biomaterial for bone implants.
Recent remarkable advances in the field of nanotechnology has been achieved in the last few years especially in the fabrication of sensors that have wide number of applications. Nanomaterials are the ...foundation of nanotechnology that are measured on nanoscale. Carbon nanotubes (CNTs) are tube-like materials that are made up of carbon with a diameter calculating on a nanometer scale. They are originated from graphite sheet and these graphite layers seems similar to a rolled up non-stop unbreakable hexagonal like mesh structure and the carbon molecules appears at the apexes of the hexagonal structures. Depending upon the number of carbon layers, carbon nanotubes can be single-walled carbon nanotubes (SWCNTs), double-walled carbon nanotubes (DWCNTs) and multi-walled carbon nanotubes (MWCNTs). Carbon nanotubes (CNTs) can be fabricated by three main methods i.e., chemical vapor deposition, electric arc method and laser deposition method. Carbon nanotubes exhibit various characteristic properties such as high elasticity, high thermal conductivity, low density and they are chemically more inert etc. Due to these interesting properties, carbon nanotubes have played a significant role in the field of nanotechnology, electronics, optics and other fields of materials science. Carbon nanotubes are being positively applied in drug delivery, sensing, water treatment etc. Functionalization of their surface can result in highly soluble materials, which can be further derivatized with active molecules, making them compatible with biological systems. Surface functionalization enables adsorption or attachment of various molecules or antigens, which subsequently can be targeted to the desired cell population for immune recognition or a therapeutic effect. In this review, properties of carbon nanotubes and their clinical applications such as medical diagnostics and drug delivery are being discussed. Here, antibacterial as well as antifungal activity of carbon nanotubes are also being reviewed.
•The PDA@Ag coating on α-TCP cement was prepared conveniently and efficiently.•The effect of the coating on mineralization properties of cement was investigated.•The antibacterial assay of the cement ...was performed and the mechanism was analyzed.
The ideal orthopedic material demands excellent antimicrobial properties and bioactivity after initial implantation in vivo. In this paper, a polydopamine (PDA) film was prepared by dopamine self-polymerization on α-tricalcium phosphate (α-TCP) cement, and then silver (Ag) particles were immobilized in-situ on the surface of PDA via a dipping method. The presence of PDA and Ag in the composition of modified cement was confirmed by XPS. The results showed that after the modification of PDA coating and Ag particles, the roughness and contact angle of the cement increased from 36.4 nm to 120 nm and 18.8° to 58.8°, respectively. Moreover, the mineralization capacity of modified cement was considerably enhanced, generating dense hydroxyapatite (HA) layer with a thickness of 3.04 μm. Furthermore, the modified cement was revealed to provide antibacterial rate over 99 %. It is suggested that good bioactivity and antimicrobial properties of the cement can be achieved using the promising method.
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•ZIF-8 has antibacterial properties superior to ZnO, a benchmark nanomaterial.•ZIF-8 displays variable antibacterial performance in different liquid environments.•Degradation pathways ...and by-products affect MOFs’ antibacterial performance.•ZIF-8 degrades more in culture media than in deionized water, and faster than ZnO.•MOFs’ aqueous stability must be fully understood for their application development.
The stability and degradation characteristics of metal–organic frameworks (MOFs) in liquid media dictate their use in biomedical engineering applications. In this study, the antibacterial property of a zinc-based MOF, zeolite imidazolate framework-8 (ZIF-8), against gram-negative Escherichia coli (E. coli) is studied in comparison with ZnO, a widely-used antimicrobial agent. Superior antibacterial property of ZIF-8 was demonstrated and the reason was elucidated by new insights on the stability of ZIF-8 in bacterial culture media. Contrary to the widely held notion that ZIF-8 is stable in aqueous media, inductively coupled plasma-optical emission spectrometry and UV–Vis adsorption spectroscopy revealed the release of zinc ions and 2-methyilimidazolate molecules in the culture media. Electron microscopy and X-ray diffractometry revealed that the degradation of ZIF-8 is enhanced by the reaction of released zinc ions with phosphate ions in phosphate-buffered saline (PBS) or with organic moieties in Luria Bertani (LB) media, resulting in stronger antibacterial properties of ZIF-8 than that of ZnO. In fact, due to the affinity of ions and organic constituents in the cell media towards the building block of ZIF-8 structure, a higher amount of ZIF-8 degrades in LB and PBS media (70–80 wt%) than in pure water (22 wt%) after 24 h of immersion. The results of the present investigation strongly advocate the importance of stability study on MOFs in developing their biomedical applications, in terms of its efficacy, biosafety and eco-safety.
Improving antibacterial performance is one of the prerequisites for the clinical application of bacterial cellulose (BC)-based dressings. In this study, a novel copper (Cu) ion loaded BC-based ...antibacterial wound dressing was prepared via codeposition of polydopamine (PDA) and copper ion. The scanning electron microscope (SEM) results showed that the copper ion/PDA coating was more uniform than the PDA coating, and the 3D nanopore structure of BC was retained in Cu
@PBC. Cu ions were immobilized by forming a chelate with PDA. The thermal stability and mechanical properties of the Cu
@PBC dressing decreased with the addition of copper ions. Cu
@PBC-2 film with a certain amount of copper sulfate used (10 nM) exhibited favorable antibacterial properties against both S. aureus and E. coli without obvious cytotoxicity. The results of the in vivo study also demonstrated that the Cu
@PBC-2 film can eliminate S. aureus infections and inflammatory response, promote collagen deposition, capillary angiogenesis, hair follicle growth and wound healing. These results suggest that the Cu
@PBC-2 film has prospective application as a wound dressing.
Developing sodium alginate (SA)/chito-oligosaccharide (COS) beads with antibacterial properties is highly appealing for food industrial applications. Herein, in this paper, the different ...viscosity-average molecular weight of SA/COS polyelectrolyte (SCP) gel beads were prepared by adding a low concentration of calcium ions (Ca2+) as crosslinker and their size, mechanical property, microscopic morphology, elemental composition, and thermal stability of the gel beads were characterized. Furthermore, the morphological changes of gel beads in in vitro simulated digestion were investigated. A time-dependent co-culture assay was used to explore the antibacterial effect of gel beads on Staphylococcus aureus and Escherichia coli. The results showed that as the viscosity-average molecular weight (Mv) of SA decreased, the bursting strength faded, the thermal stability decreased, and the swelling index increased. Similarly, increasing the Ca2+ content could also regulate the characteristics of the gel beads, such as diminishing size, increasing the bursting strength, making the surfaces rough, and producing the network structure in the cross-section. In addition, Ca2+ competes with COS in cross-linking with the carboxyl groups of SA, which leads to a decrease in the content of N element on the surfaces of the gel beads and to a weakening of the antibacterial effect. After the addition of COS, the gel beads obtained antimicrobial effects and a denser cross-sectional structure. The present study could provide a theoretical basis for the design and development of novel gel foods in the food industry.
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•Edible gel bead was made of sodium alginate (SA) and chito-oligosaccharide (COS).•With the addition of Ca2+, the network structure inside the gel beads appeared.•Ca2+ would compete with the COS for the binding site of SA.•The addition of COS endows the gel bead with excellent antimicrobial activity.
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Diabetic wound treatment remains a major challenge due to the difficulties of eliminating bacterial biofilm and relieving wound hypoxia. To address these issues simultaneously, a ...multifunctional Dex-SA-AEMA/MnO2/PDA (DSAMP) hydrogel platform was developed with excellent biocompatibility and porous structure. The hydrogel could absorb the exudate, maintain humidity and permeate oxygen, which was prepared by encapsulating polydopamine (PDA) and manganese dioxide (MnO2) into Dex-SA-AEMA (DSA) hydrogel by UV irradiation. With the addition of PDA, the DSAMP hydrogel was proved to eliminate the biofilm after NIR photodynamic therapy (PTT, 808 nm) irradiation at 54 °C. Furthermore, in order to mitigate hypoxia wound microenvironment, MnO2 nanoparticles were added to convert the endogenous hydrogen peroxide (H2O2) into oxygen (O2, 16 mg L−1). The diabetic wound in vivo treated by DSAMP hydrogel was completely healed on 14 days. It was revealed that the DSAMP hydrogel possessed a great potential as dressing for diabetic chronic wound healing.
Most recently, silver nanoparticles due to antibacterial properties have been considered in medical science. So the aim of the study was green synthesis of silver nanoparticles using Berberis ...vulgaris leaf and root aqueous extract and its antibacterial activity. After collection, identification and extraction of Berberis vulgaris was performed production of silver nanoparticles. In the study effect of parameters such as AgNO3 concentration (0.5, 1, 3, 10 mM), aqueous extract (3, 5, 10, 15, 30 mL) and contact time (1, 2, 6, 12, 24 h) were investigated in the synthesis of nanoparticles and also the antibacterial effect of these nanoparticles was studied on Escherichia coli and Staphylococcus aureus bacteria by Disk diffusion test and Minimum Inhibitory Concentration test (MIC). According to XRD results and analysis of TEM, nanoparticles have spherical shapes and size of 30 to 70 nm. On the other hand antibacterial tests showed these nanoparticles have more antibacterial activity more than other extracts. Result showed the biosynthesis of silver nanoparticles using aqueous extract of Berberis vulgaris is a clean, inexpensive and safe method that has not been used any toxic substance and consequently does not side effects and this nanoparticles has a high antibacterial activity.
•Green Synthesis of Silver Nanoparticles Using Berberis Vulgaris Leaf and Root Aqueous Extract•Investigation of Antimicrobial Properties using Synthesis of Silver Nanoparticles•Doing Disc Diffusion Test and Minimum Inhibitory Concentration Test•Ultraviolet-visible spectroscopyto identify nanoparticles synthesized•X-ray diffraction spectroscopyto identify nanoparticles synthesized•Dynamic Light Scattering Spectroscopy for identification nanoparticles synthesis•Transmission electron microscopy spectroscopy for identification nanoparticles synthesis
Glucose is abundant in nature and can be found in various sources. In this study, we developed multifunctional carbon dots (CDs) with glucose and poly(ethyleneimine) (PEI), which were further ...quaternized using a facile approach. The CDs are designed to possess both anti-bacteria and gene delivery capabilities. The inherent property was characterized with TEM, NMR, FTIR and fluorescent spectroscopy. Antibacterial activity was evaluated with Broth minimum inhibitory concentration (MIC) assay on both Gram-positive and Gram-negative bacteria. The CDs showed excellent inhibitation to both bacteria. The expression of CDs condensed plasmid DNA in HEK 293T cells was investigated with luciferase expression assay. Gene transfection capability of the quaternized CDs was found to be up to 10 super(4) times efficient than naked DNA delivery.
Conductive hydrogels are ideal for preparing wearable sensing devices due to their excellent stretchability and flexibility. However, most hydrogels exhibit poor frost resistance, weak water ...retention, and lack of biocompatibility and antibacterial properties. In this paper, polyvinyl alcohol (PVA) was used as the skeleton, water, and glycerol formed a binary solvent system, and lithium chloride and polyhexamethylene biguanide hydrochloride (PHMB) were added to the hydrogel system as functional materials. The participation of glycerol not only endowed PVA hydrogels with excellent frost resistance but also formed hydrogen bond interaction with PVA, which improved the mechanical properties of hydrogels. Meanwhile, adding PHMB made hydrogel performs excellent antibacterial properties, effectively killing E. coli (Gram-negative bacteria) and B. subtilis (Gram-positive bacteria). Furthermore, based on the introduction of LiCl, the hydrogel displayed high electrical conductivity. The prepared hydrogel sensor could repeatedly detect and distinguish between various human activities, such as walking, frowning, and speaking. Therefore, prepared multifunctional hydrogels possessed excellent application potential in the medical field, health monitoring, and other fields.
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•The hydrogel has high conductivity, water retention and antibacterial properties.•Hydrogel sensor can detect the movement characteristics of various human joints.•The hydrogel sensor has good stability and repeatability.
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