Processing and properties of new generation radiation shielding nano composites

Electromagnetic radiation from equipments in medical diagnostic centers or nuclear reactors causes ionization including gamma rays and x-rays that are well known to be very harmful to human health. Therefore, flexible, light-weighed and environmentally friendly shielding materials that can replace toxic and very heavy Pb based materials are required. In the present work, synthesized and surface modified micro/nano B4C particles are distributed within polymeric matrices in order to obtain flexible shielding materials. The effect of surface functionalization and concentration of boron carbide on the distribution characteristics of boron carbide and the final properties of the composites are examined

Recent Advances in Health Biotechnology During Pandemic

The outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which emerged in 2019, cut the epoch that will make profound fluctuates in the history of the world in social, economic, and scientific fields. Urgent needs in public health have brought with them innovative approaches, including diagnosis, prevention, and treatment. To exceed the coronavirus disease 2019 (COVID-19) pandemic, various scientific authorities in the world have procreated advances in real time polymerase chain reaction (RT-PCR) based diagnostic tests, rapid diagnostic kits, the development of vaccines for immunization, and the purposing pharmaceuticals for treatment. Diagnosis, treatment, and immunization approaches put for- ward by scientific communities are cross-fed from the accrued knowledge of multidisciplinary sciences in health biotechnology. So much so that the pandemic, urgently prioritized in the world, is not only viral infections but also has been the pulsion in the development of novel approaches in many fields such as diagnosis, treatment, translational medicine, virology, mi- crobiology, immunology, functional nano- and bio-materials, bioinformatics, molecular biol- ogy, genetics, tissue engineering, biomedical devices, and artificial intelligence technologies. In this review, the effects of the COVID-19 pandemic on the development of various scientific areas of health biotechnology are discussed

Preparation and characterization of graphene oxide quantum dots/silver nanoparticles and investigation of their antibacterial effects

Water, constituting 75% of Earth and vital for sustaining life, faces global contamination challenges, causing approximately 2 million annual deaths from waterborne diseases, as reported by the World Health Organization. Technological strides in water purification leverage antibacterial materials to combat this issue. At the forefront is silver nanoparticles (AgNP), renowned for antimicrobial efficacy. Their action involves damaging bacterial cells and hindering metabolism, causing structural and physiological alterations in microbial membranes. Graphene oxide (GO) emerges as a potent biocide, and when combined with AgNP, it enhances antibacterial activity. The resulting composite, known as antibacterial graphene oxide quantum dots (GOQD), exhibits photocatalytic behavior when exposed to sunlight or UV rays, generating reactive oxygen species (ROS). This synergistic composite, particularly the GOQD/AgNP combination, proves effective in eliminating bacteria and fungi from water. In a recent study, GOQD was synthesized, and the GOQD/AgNP combination was prepared. Structural analyses, utilizing techniques such as FTIR, Zeta sizer, and TEM, revealed heightened antibacterial activity with increasing AgNP ratios. The GOQD/AgNP samples formed inhibition zones of 11.75 mm, 10 mm, and 9.88 mm against pathogenic bacteria Escherichia coli (E. coli) , Salmonella typhi (S. typhi) , and Staphylococcus aureus (S. aureus) , respectively. Notably, the GOQD/AgNP composite demonstrated a synergistic antibacterial effect, showcasing its potential for widespread applications. This material holds promise for deployment in drinking water treatment plants and water storage tanks, ensuring water safety for consumption. Beyond water purification, the composite’s antibacterial properties hint at significant potential in medical and industrial realms, marking a crucial step toward safeguarding water sources and enhancing global public health

Lavandula Stoechas Extract Incorporated Polylactic Acid Nanofibrous Mats as an Antibacterial and Cytocompatible Wound Dressing

In recent years, great efforts have been devoted to the design and production of bioactive wound dressings that promote skin regeneration and prevent infection. Many plant extracts and essential oils have been widely accepted in traditional medicine for a wide variety of medicinal purposes, especially wound healing. Over the past decade, many studies have focused on manufacturing and designing wound dressings containing plant compounds and extracts. In this study, Lavandula stoechas extract (LSE) (0.25 %, 0.5 %, and 1%wt) incorporatedpolylactic acid (PLA) nanofibrous mats were successfully produced and characterized. Microstructural analysis by SEM revealed that the fiber diameter changed with the increase in the amount of LSE. Also, the nanofibrous mats were evaluated for their in vitro antibacterial, cytotoxicity, and wound healing properties for their use as a wound dressing material. According to the results of the disc diffusion test, PLA nanofibrous mats containing LSE %1 showed 9.65 ± 0.46 and 7.37 ± 0.03 inhibition zone (mm) against E. coli and S. aureus, respectively. According to the results of the in vitro wound healing assay, mats containing 0.5 % LSE showed better-wound closure activity compared to the control. Our results show that LSE-incorporated nanofibrous dressings can be an effective alternative with good antimicrobial activity

Antibacterial and Cellular Behavior of PLA-based Bacitracin and Zataria Multiflora Nanofibers Produced by Electrospinning Method

In this study, poly(lactic-acid) (PLA) polymer-based nanofiber (NF) was obtained by the electrospinning method. Antioxidant Zataria Multiflora (ZM, essential oil extract) and antibiotic effective bacitracin (BAC) materials were added to 8% PLA. ZM essential oil was extracted with Rotary and antioxidant components were investigated using GC-MS. While carvacrol constitutes 50% as the main component of ZM, it was seen as 48.06% carvacrol and 25.47% thymol as a content area. It was analyzed that ZM has a total antioxidant rate of 99.87% with 20 components. In antibacterial tests, PLA/BAC/ZM NF showed the best inhibition growth on all microorganisms (Escherichia coli, Staphylococcus aureus, Bacillus cereus, Staphylococcus epidermidis, Bacillus subtilis). In cell XTT cytotoxicity tests, it was observed that the PLA/BAC/ZM NF used in adhesion and 4 ',6-diamidino-2-phenylindole (DAPI) results showed very good adhesion to cells

In Situ Synthesis and Cell Line Studies of Nano-Hydroxyapatite/Graphene Oxide Composite Materials For Bone Support Applications

The current work presents and discusses the findings of on the structural, chemical and thermal properties of in situ synthesis of graphene oxide-hydroxyapatite (GO/HA) nanocomposite materials doped with graphene oxide (w/w) at different ratios of 0%, 0.1%, 0.5% and 1% for bone tissue support applications. Microstructure and crystallinity were investigated by Fourier transform infrared spectroscopy (FT-IR), Raman spectroscopy, X-ray diffraction (XRD), thermogravimetric analysis (TGA), pore structures by Brunauner-Emmett-Teller (BET) analysis, Dynamic light scattering (DLS). Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) were performed to characterize the morphology of the bone support scaffold materials. The attachment and cell viability of fibroblast NIH/3T3 cells were observed on the synthesized bone support composite materials. Excellent proliferation of bone support scaffolds containing 0.5% and 1% GO (w/w) was observed by fluorescence microscopy using 3,3′ -Dihexyloxacarbocyanine iodide (Dio-6), 4′ ,6-diamidino-2-phenylindole (DAPI), MitoRed and Anti-Vinculin. The innovative materials revealed in this study demonstrated that GO and HA promoted cell proliferation and cell adhesion with their well-compatible properties and helped cell penetration and colonization by increasing the surface area of GO, making them promising materials for bone support applications

Targeted drug delivery and vaccinology approaches using virus-like particles for cancer

Nanotechnology has the potential to make significant alterations in the treatment of diseases such as cancer through targeted drug delivery nanoparticles. Virus-like particles (VLPs) are composed of the capsid proteins that do not carry the viral genome and are also noninfectious. VLPs are self-assembling competent protein structures with identical or highly related structures to their corresponding native viruses. VLPs that have precise 3D nanostructures exhibit a notable diversity in shapes and structures. They can be produced in large quantities through biological amplification and growth. External protein inserts can be displayed through genetic methods or chemical modifications. Functionalized VLPs when used as delivery systems have the ability to target with specificity and can attract macrophages for the destruction of cancer cells. The capability to target tumors for the delivery of therapeutic agents is an important goal of the design approaches of VLPs. Against the current problems in cancer therapies, delivery systems using VLPs are an arising and promising field with the potential to exhibit solutions. Cancer therapies require specific targeting of the diagnostic element or the drug to tumor cells without binding to or affecting healthy cells and tissues. Specialization of the VLPs provides an opportunity for using them as site-specific drug delivery systems in cancer therapy while reducing the systemic toxicity and the overall damage to healthy cells. With fewer side effects, immunotherapy is also a promising alternative for cancer treatment by primarily activating the host's immune system. Cancer vaccines are aimed at inducing an immune response in the host, thereby generating a defensive mechanism against tumor cells. VLPs can be used as a vaccine without the requirement of any adjuvant due to their naturally optimized particle size and their repetitive structural order. Therefore, the aim of this review is to provide basic information about VLPs and describe previous research on VLPs used as drug and vaccine delivery systems and their applications in different types of cancer

Processing and properties of boron carbide (B4C) reinforced LDPE composites for radiation shielding

In the present work, boron carbide (B4C) particles were synthesized with sol-gel technique following with heat treatment at 1500 °C in an argon atmosphere. 3-(Triethoxysilyl)-propylamine, a silane coupling agent, was doped on to the surface of synthesized B4C particles. The surface modified B4C particles were embedded in LDPE matrix in order to obtain flexible, lightweight and environmentally friendly shielding materials. The effect of surface functionalization and concentration of boron carbide on its distribution characteristics in the polymer matrix and its effects on the mechanical and neutron shielding properties of the composites are examined. The results showed that high purity-fully crystalline B4C powders with polyhedral-equiaxed morphology in the size range of 20 nm–500 nm were produced. It was found that even the very low amount (0.6–1.7 wt%) of incorporated nano/sub-micron B4C particles in LDPE matrix improved the neutron shielding (up to 39%), tensile strength (9.3%) and impact resistance (8%) of the composites

Selenium and Clarithromycin Loaded PLA-GO Composite Wound Dressings by Electrospinning Method

Diabetic wounds are very problematic wounds that have a high risk of infection. The healing process of wounds in diabetic patients is more complicated than others. Wound dressing preparation is one of the promising treatment modalities for repairing damaged tissues in diabetic patients. The aim of this study is to demonstrate the antibacterial effects of drug release of clarithromycin from poly(lactic acid) (PLA) nanofibers incorporated with selenium (Se) and graphene-oxide (GO) to reveal their wound healing potential. In the present study, optimized PLA was combined with graphene oxide (GO) with a concentration of 0.45 wt%, 1wt%, 1.50 wt%, 2wt%, 2.50 wt%, and 3wt%, respectively, and the combination was produced by modified Hummers method. After that, optimized PLA/GO was incorporated with Se and clarithromycin with PLA with the percentage by weight of 1:1, nanofiber patches were successfully produced by the electrospinning technique. In vitro antibiotic test, cell culture tests (cytotoxicity test, cell adhesion, and in vitro wound healing assay), morphological analysis (SEM), molecular interactions between the components (FT-IR), tensile strength, and physical analysis (viscosity, surface tensile, density and conductivity tests) were carried out after production of nanofiber patches. According to the results, the average pore size of 8wt% PLA þ 1 wt% GO þ 1wt% Se þ 1wt% clarithromycin nanofiber is 640 nm. Moreover, 8wt% PLA þ 1wt% GO þ 1 wt% Se þ 1 wt% clarithromycin has the highest viscosity and surface tension value than others with the values of 253.8 ± 6.67 mPas and 31.62 ± 2.13 mN/m, respectively. Finally, it was observed that Se-incorporated electrospun nanofibers had antibacterial effects and are highly promising wound healing materials. To sum up, the prepared nanofibers illustrated important suitable mechanical properties, controlled release and antibacterial effect and results showed that Se incorporated PLA-GO-drug composite is a promising wound healing material