Current Nanoscience - Volume 18, Issue 4, 2022

Copper (Cu) has been used in agriculture for centuries as a standard bactericide/fungicide due to its low cost, superior disease control efficacy, and relatively low toxicity to humans. However, the extensive use of copper as a pesticide has caused the development of Cu-tolerant microorganisms as well as negative environmental impacts due to the accumulation of copper in soil and bodies of water. Therefore, there is a strong demand for advanced Cu products and alternatives to minimize the Cu footprint in the environment. This minireview will cover the limitations of Cu usage and the strategies being investigated to develop advanced Cu materials and alternatives for crop protection using nanotechnology.

Nanotechnology is a multidisciplinary domain that involves overlapping areas such as nanomaterials, nanoelectronics, and nanobiotechnology. Herbal medicine is a significant component of traditional medicine and has been a part of treating many diseases. Asian people have been using these herbal medicines for decades. Still, herbal extracts' therapeutic efficacy and pharmaceutical application are associated with many factors such as poor bioavailability, low solubility, permeability, and lack of targeting potential. In the present work, we have reviewed thriving strategies for the targeted drug delivery of phytoconstituents and critically explained the most recent progressions on emerging novel nano-phytomedicine-based materials as herbal medicines carriers. Nanotechnologybased clinical trial studies targeting herbal bioactive compounds were discussed. Advancements in nanotechnology-based drug delivery systems intended to enhance cellular uptake, improved pharmacokinetics, and effectiveness of herbal drugs have facilitated the powerful targeting of specific agents against diseases. This review provides insight into the current progress and future opportunities for nanomedicines as potential curative targets for the delivery of herbal bioactive compounds. This information could be used as a platform for the future expansion of multi-functional nano constructs for the advanced detection of diseases and functional drug delivery of phytoconstituents.

Nanotechnology is one of the most important modern sciences that has integrated all sectors of science. Nanotechnology has been applied in the agricultural sector in the last ten years in pursuit of increasing agricultural production and ensuring food security. Plant biotechnology is an essential science that is concerned with plant production. The use of nanotechnology in plant biotechnology under controlled conditions has facilitated the understanding of important internal mechanisms of the plant biological system. The application of nanoparticles (NPs) in plant biotechnology has demonstrated an interesting impact on in vitro plant growth and development. This includes the positive effect of the NPs on micropropagation, callus induction, somatic embryogenesis, cell suspension culture, and plant disinfection. In addition, other biotechnology processes, including the genetic transformation of plants, plant conservation, and secondary metabolite production have improved by the use of NPs. Furthermore, nanotechnology is used to improve plant tolerance to different stress conditions that limit plant production. In this review article, we attempt to consolidate the achievements of nanotechnology and plant biotechnology and discuss advances in the applications of nanotechnology in plant biotechnology. It has been concluded that more research is needed to understand the mechanism of nanoparticle delivery and translocation in plants in order to avoid any future hazardous effects of nanomaterials. This will be key to the achievement of magnificent progress in plant nanobiotechnology.

Background: Today, SARS-CoV-2 (COVID-19), a viral disease caused by the novel coronavirus (a tiny crowned virus), has become one of the threats for human beings all over the world and caused the death of millions of people worldwide. Many vaccines have been developed and administered to people in several countries; however, due to their propensity to create new strains, it appears that curing all corona strains will be challenging. So, it is necessary to identify the structure of the virus, mechanism of action, and its antiviral activities against drugs and other functional materials. Methods: AgNPs have unique physicochemical and antimicrobial properties. This review describes the structure and nature of the virus and the mechanism of action of an antiviral drug such as silver nanoparticles (AgNPs) with the virus. In addition, different methods for synthesis of AgNPs, application of AgNPs as an antiviral agent against influenza virus, human immuno deficiency virus (HIV), herpes simplex virus type 1 (HSV-1), hepatitis B virus (HBV), polio virus, respiratory syncytial virus (RSV), are discussed. Also, the most probable applications and properties of AgNPs that can help prepare it as an antiviral agent are discussed. Results: The use of AgNPs against various viruses, including the coronavirus family, is found to be effective; therefore, it can be considered for the development of antiviral agents, disinfectants, antiviral coated mask, and their therapeutic use against the treatment of novel coronavirus with minimum side effect and great efficiency. Conclusion: AgNPs were successfully used for the treatment of various viral diseases of the coronavirus family such as H1N1, H3N2, influenza, even for SARS and MERS coronaviruses. AgNPs coated masks, disinfectants, fabrics, wipes, and inhalation systems are effective for the inhibition of SARS-CoV-2 infection. Since sanitizers have a temporary effect, the development of some other potential alternatives having low toxicity, ease of use, long lasting efficiency, health cautiousness, minimum side effect, sustainable fabrics is required.

Background: The unique ability of carbon to form a wide variety of allotropic modifications has ushered in a new era in material science. Tuning the properties of these materials by functionalization is a must-have tool for their design customized for a specific practical use. The exponentially growing computational power available to researchers allows for the prediction and thorough understanding of the underlying physicochemical processes responsible for the practical properties of pristine and modified carbons using the methods of quantum chemistry. Methods: This review focuses on the computational assessment of the influence of functionalization on the properties of carbons and enabling desired practical properties of the new materials. The first section of each part of this review focuses on graphene with nearly planar units built from sp2- carbons. The second section discusses patterns of sp²-carbons rolled up into curved 3D structures in a variety of ways (fullerenes). The overview of other types of carbonaceous materials, including those with a high abundance of sp3-carbons, including nanodiamonds, can be found in the third section of each manuscript’s part. Conclusion: The computational methods are especially critical for predicting electronic properties of materials such as the bandgap, conductivity, optical and photoelectronic properties, solubility, adsorptivity, the potential for catalysis, sensing, imaging, and biomedical applications. We expect that introduction of defects to carbonaceous materials as a type of their functionalization will be a point of growth in this area of computational research.

Background: Currently, the environmental and biological samples, such as water, soil, vegetables, etc., are highly contaminated with metal ions, anions and pesticides. For analysis of these toxic substances from the environmental and biological samples, sophisticated and expensive instruments are being used. The present work deals with the development of a simple, faster, sensitive and economical method for the analysis of toxic substances present in different samples. Methods: The general methods for synthesis and characterization of metallic (Ag, Au, Cu and graphene) nanoparticles and conductive polymer for the development of conductive nano-ink and fabrication of paper substrate by direct deposition and laser, wax, or inkjet printing techniques, have been reported. Results: Paper-based sensors fabricated with different nanomaterials used as colorimetric, electrochemical and fluorescence-based chemical sensors for the quantitative determination of pesticides and toxic metal ions in various biological and clinical samples have been comprehensively discussed in this review. Conclusion: The low-cost, rapid, eco-friendly, flexible, portable, and paper-based sensors using nanoparticles (NPs) are in demand for on-site detection of different chemical constituents present in various environmental, biological and clinical samples.

Titanium dioxide (TiO2) is a known semiconducting material that has been effectively used in photo-catalytic processes to promote environmental sustainability. It can also reduce the environmental chaos caused by fossil fuel combustion to meet energy demands. Many studies have proposed modifications of the large band gap in TiO2, which causes visible light activation during photocatalytic reactions when exposed to UV light radiation. Therefore, many alterations, such as the doping of nonmetals and metals to TiO2, have been investigated. In this review, we discuss advanced preparation techniques for TiO2 with various dopants and techniques. Characterization methods were performed to evaluate the structural, morphological, and optical properties of TiO2 doped with metal and nonmetal ions, such as S, C, N, Fe, B, W, Ag, Nb, and Zn, by various synthesis methods. We also explored the experimental and other characteristics to determine the best doping component for use in real-time applications.

Objective: In the present investigation, thermal conductivity and viscosity properties of water-based SiO2-ND hybrid nanofluid were measured, experimentally. Methods: Nanofluids were prepared by using a two-step method and with three different (0.5%, 0.75%, and 1%) concentrations. Every concentration had three different SiO2-ND mixtures (50% SiO2 - 50% ND, 33% SiO2 - 66% ND, 66% SiO2 - 33% ND). Results: The most stable sample was measured as -33.4 mV. Measurements of viscosity and thermal conductivity were done from 20°C to 60°C at every 10°C. Thermal conductivity data were measured by thermal conductivity analyzer and viscosity data were measured by tube viscometer. The highest thermal conductivity enhancement was measured for 1% SiO2^0.33: ND ^0.66 at 40°C and the highest relative dynamic viscosity was calculated as 4.19 for 1% SiO2^0.33: ND ^0.66 at 40°C. A comparison table is also given to show the zeta potential values-concentration relations. Conclusion: Finally, two different correlations for predicting thermal conductivity and viscosity were proposed for practical usage.

Background: The re-emergence of infectious diseases and the increasing rate of the appearance of many antibiotic-resistant strains are major public health concerns. Zinc oxide nanoparticles (ZnO-NPs) have a great antibacterial effect. Few reports stated the antibacterial effect of low electric field (LEF). Objective: The paper aimed to study the antibacterial effect of LEF at low frequency and investigate the antibacterial effectiveness of using LEF in synergy with ZnO-NPs. Methods: Pseudomonas aeruginosa and Staphylococcus aureus were examined as models for Gramnegative and Gram-positive bacteria, respectively. The bacterial suspension was exposed to different concentrations of Zn-NPs ranging from 100-1600 μg/ml or 2 V/cm, 500 Hz AC electric field for 5 min. ZnO-NPs were prepared and characterized by UV-Vis spectroscopy, XRD, FTIR, TEM, and SEM. The combined effect of LEF exposure with each ZnO-NPs concentration was assessed. Results: 1600 μg/ml ZnO-NPs cause 41.93% and 48.15% death, LEF produces 20.88% and 28.03% death, and the synergetic effect causes 50.41% and 70.27% death for P. aeruginosa and S. aureus, respectively. The death percentages were correlated with DNA concentration and deformation, reactive oxygen species concentration, and ultrastructure changes. Conclusions: LEF has antibacterial properties and can be used in combination with ZnO-NPs to increase its lethal effect.