From nature to nanotechnology: The interplay of traditional medicine, green chemistry, and biogenic metallic phytonanoparticles in modern healthcare innovation and sustainability

As we navigate the modern era, the intersection of time-honoured natural remedies and contemporary scientific approaches forms a burgeoning frontier in global healthcare. For generations, natural products have been foundational to health solutions, serving as the primary healthcare choice for 80% to 85% of the world's population. These herbal-based, nature-derived substances, significant across diverse geographies, necessitate a renewed emphasis on enhancing their quality, efficacy, and safety. In the current century, the advent of biogenic phytonanoparticles has emerged as an innovative therapeutic conduit, perfectly aligning with principles of environmental safety and scientific ingenuity. Utilizing green chemistry techniques, a spectrum of metallic nanoparticles including elements such as copper, silver, iron, zinc, and titanium oxide can be produced with attributes of non-toxicity, sustainability, and economic efficiency. Sophisticated herb-mediated processes yield an array of plant-originated nanomaterials, each demonstrating unique physical, chemical, and biological characteristics. These attributes herald new therapeutic potentials, encompassing antioxidants, anti-aging applications, and more. Modern technology further accelerates the synthesis of natural products within laboratory settings, providing an efficient alternative to conventional isolation methods. The collaboration between traditional wisdom and advanced methodologies now signals a new epoch in healthcare. Here, the augmentation of traditional medicine is realized through rigorous scientific examination. By intertwining ethical considerations, cutting-edge technology, and natural philosophy, the realms of biogenic phytonanoparticles and traditional medicine forge promising pathways for research, development, and healing. The narrative of this seamless integration marks an exciting evolution in healthcare, where the fusion of sustainability and innovation crafts a future filled with endless possibilities for human well-being. The research in the development of metallic nanoparticles is crucial for unlocking their potential in revolutionizing fields such as medicine, catalysis, and electronics, promising groundbreaking applications with enhanced efficiency and tailored functionalities in future technologies. This exploration is essential for harnessing the unique properties of metallic nanoparticles to address pressing challenges and advance innovations across diverse scientific and industrial domains.

Polarization-Dependent Sum-Frequency-Generation Spectroscopy for In Situ Tracking of Nanoparticle Morphology

The surface structure of oxide-supported metal nanoparticles can be determined via characteristic vibrations of adsorbed probe molecules such as CO. Usually, spectroscopic studies focus on peak position and intensity, which are related to binding geometries and number of adsorption sites, respectively. Employing two differently prepared model catalysts, it is demonstrated that polarization-dependent sum-frequency-generation (SFG) spectroscopy reveals the average surface structure and shape of the nanoparticles. SFG results for different particle sizes and morphologies are compared to direct real-space structure analysis by TEM and STM. The described feature of SFG could be used to monitor particle restructuring in situ and may be a valuable tool for operando catalysis.

Recent Advances in Hybrid Materials of Metal Nanoparticles and Polyoxometalates

Polyoxometalates (POMs), anionic metal-oxygen nanoclusters that possess various composition-dependent properties, are widely used to modify the existing properties of metal nanoparticles and to endow them with new ones. Herein, we present an overview of recent advances in hybrid materials that consist of metal nanoparticles and POMs. Following a brief introduction on the inception of this area and its development, representative properties and applications of these materials in various fields such as electrochemistry, photochemistry, and catalysis are introduced. We discuss how the combination of two classic inorganic materials facilitates cooperative and synergistic behavior, and we also give personal perspectives on the future development of this field.

Direct Dry Synthesis of Supported Bimetallic Catalysts: A Study on Comminution and Alloying of Metal Nanoparticles

Ball milling is growing increasingly important as an alternative synthetic tool to prepare catalytic materials. It was recently observed that supported metal catalysts could be directly obtained upon ball milling from the coarse powders of metal and oxide support. Moreover, when two compatible metal sources are simultaneously subjected to the mechanochemical treatment, bimetallic nanoparticles are obtained. A systematic investigation was extended to different metals and supports to understand better the mechanisms involved in the comminution and alloying of metal nanoparticles. Based on this, a model describing the role of metal-support interactions in the synthesis was developed. The findings will be helpful for the future rational design of supported metal catalysts via dry ball milling.

Silver Nanoparticles Exert Apoptotic Activity in Bladder Cancer 5637 Cells Through Alteration of Bax/Bcl-2 Genes Expression

Bladder cancer is defined as a urinary tract malignancy that threatens men's and women's health. Due to the side effects of common chemotherapies, novel therapeutic strategies are necessary to overcome the issues concerning bladder cancer treatments. Nanotechnology has been suggested as a means to develop the next-generation objectives of cancer diagnosis and treatment among various novel therapies. Owing to the special characteristics that they can offer, silver nanoparticles (AgNPs) were investigated in this study to evaluate their apoptotic impact on bladder cancer 5637 cells. In this study, an MTT assay was conducted and appropriate concentrations of AgNPs were selected. Moreover, reactive oxygen species (ROS) production and apoptosis levels were determined using fluorimetric and Annexin/PI flow cytometry assays, respectively. Moreover, the activity of caspase 3,7, mRNA expression of Bax (Bcl-2-associated X) and Bcl-2 (B-cell lymphoma 2) were assessed based on colorimetric and qRT-PCR methods, respectively. The results indicated that AgNPs can significantly reduce the viability of 5637 cells in a dose-dependent mode as well as having the ability to elevate ROS production. Flow cytometry data showed that AgNPs lead to a remarkable increase in the apoptosis rate as compared with the control. Consistent with this, the induction of apoptosis was revealed by the overexpression of Bax, accompanied by a reduction in Bcl-2 expression compared to the control. Furthermore, AgNPs remarkably stimulated caspase 3,7 activation. In summary, AgNPs can mediate apoptosis in 5637 cells via excessive ROS formation, up-regulating Bax/Bcl-2 expression, and caspase 3,7 activation.

Electronically Engineering Water Resistance in Methane Combustion with an Atomically Dispersed Tungsten on PdO Catalyst

Improving the low-temperature water-resistance of methane combustion catalysts is of importance for industrial applications and it is challenging. A stepwise strategy is presented for the preparation of atomically dispersed tungsten species at the catalytically active site (Pd nanoparticles). After an activation process, a Pd-O-W₁ -like nanocompound is formed on the PdO surface with an atomic scale interface. The resulting supported catalyst has much better water resistance than the conventional catalysts for methane combustion. The integrated characterization results confirm that catalytic combustion of methane involves water, proceeding via a hydroperoxyl-promoted reaction mechanism on the catalyst surface. The results of density functional theory calculations indicate an upshift of the d-band center of palladium caused by electron transfer from atomically dispersed tungsten, which greatly facilitates the adsorption and activation of oxygen on the catalyst.

The Role of Metallic Nanoparticles in Inhibition of Mycobacterium Tuberculosis and Enhances Phagosome Maturation into the Infected Macrophage

This review focuses on the role of gallium (Ga) nanoparticles (NPs) to enhance phagosome maturation into the Mycobacterium tuberculosis-infected macrophage and the role of magnetic iron NPs as nanocarriers of antituberculosis drugs. The literature shows that silver (Ag) and zinc oxide (ZnO) NPs with dimensions less than 10 nm can penetrate directly through the macrophage bilayer membrane. Ag NPs increase the permeability membrane by motiving the aggregation of proteins in the periplasmic space and forming nano-sized pores. ZnO NPs can interact with the membrane of M. tuberculosis, which leads to the formation of surface pores and the release of intracellular nucleotides. The colloidal Ag:ZnO mixture NPs with 1:1 ratio can eliminate M. tuberculosis and shows the lowest cytotoxicity effects on MCF-7 and THP-1 cell lines. Ag/ZnO nanocrystals are not able to kill M. tuberculosis alone ex-vivo. Hence, bimetallic gold (Au)/Ag NPs possessed high efficiency to inhibit M. tuberculosis in an ex-vivo THP-1 infection model. Co-delivery of mixed MeNPs into a polymeric carrier collaborated to selective uptake by macrophages through passive targeting, initial burst release of ions from the encapsulated metallic (Me) NPs, and eventually, reduction of MeNPs toxicity, and plays a pivotal role in increasing the antitubercular activity compared to use alone. In addition, Ga NPs can import drugs to the macrophage, inhibit M. tuberculosis growth, and reduce the inhibition of phagosome maturation. Magnetic encapsulated NPs exhibited good drug release properties and might be suitable as carriers of antituberculosis drugs.

Lateral Flow Genochromatographic Strip for Naked-Eye Detection of Mycobacterium Tuberculosis PCR Products with Gold Nanoparticles as a Reporter

Background

Mycobacterium tuberculosis (MTB) is a pathogen causing tuberculosis (TB) in human, and TB can cause enormous social and economic disruptions. Lateral flow test strips (LFTSs) are inexpensive, portable, disposable, rapid, and easy-to-use analytical tools.

Objective

LFTSs were prepared for the detection of MTB. LFTSs were fabricated using a new specific probe for MTB H37Rv, based on IS6110 sequence gene, and tailed with poly deoxyadenine (dA).

Material and Methods

In this experimental study, to create test and control zones, streptavidin (STP) and a 150-mer dA were dotted on a nitrocellolose membrane. Gold nanoparticles (GNPs) were conjugated with poly deoxythymidine sequence and placed on the conjugate pad. The composition of immersion buffers for sample pad and conjugate pad, running solution, solutions of GNPs-S-dT150 and STP were introduced. DNA genome of MTB and Mycobacterium bovis in clinical samples was amplified with PCR, and then detected by the LFTSs. During the assay, samples were firstly hybridized in two steps and then placed on a conjugate pad in a manner that positive and negative samples provided two and one red lines, respectively, on the detection pad.

Results

After PCR reaction with biotinylated primer, hybridization process with specific MTB probe-dA70-100 toke 10 min, and running process on the strip was performed within 5 min.

Conclusion

We showed that LFTS can discriminate a particular bacteria strain from others. The LFTSs can be redesigned for detection of other pathogenic genomes.

The Bystander Effect of Ultraviolet Radiation and Mediators

A bystander effect is biological changes in non-irradiated cells by transmitted signals from irradiated bystander cells, which causes the radiation toxic effects on the adjacent non-irradiated tissues. This phenomenon occurs by agents such as ionizing radiation, ultraviolet radiation (UVR) and chemotherapy. The bystander effect includes biological processes such as damage to DNA, cell death, chromosomal abnormalities, delay and premature mutations and micronuclei production. The most involved genes in creating this phenomenon are cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), the nuclear factor of kappa B (NFkB) and Mitogen-Activated Protein Kinases (MAPKs). Radiation generated reactive oxygen species (ROS) can damage DNA, membranes and protein buildings. Studies have shown that Vitamin C, Hesperidin, and melatonin can reduce the number of ROS and have a protective role. Silver nanoparticles (Ag NPs) are the most abundant nanoparticles produced and when they enter cells, they can create DNA damage. Studies have shown that combined treatment with UVR and silver nanoparticles could form γ-H2AX and 8-hydroxy-2'-deoxyguanosine (8-OHdG) synergistically. This article reviews the direct and the bystander effects of UVR on the nuclear DNA, the effect of radioprotectors and Ag NPs on these effects.

Metal Nanoparticle Carbon Gel Composites in Environmental Water Sensing Applications

The synthesis of organic-inorganic nanocomposites that can interact with different environmental pollutants and can be mass-produced are very promising materials for the fabrication of chemical sensor devices. Among them, metal (or metal oxide) nanoparticles doped conductive porous carbon composites can be readily applied to the production of electrochemical sensors and show enhanced sensitivity for the measurement of water pollutants, thanks to the abundant accessible and functional sites provided by the interconnected porosity and the metallic nanoparticles, respectively. In this personal account, an overview of several synthesis routes of porous carbon composites containing metallic nanoparticles is given, paying special attention to those based on sol-gel techniques. These are very powerful to synthesize hybrid porous materials that can be easily processed into powders and thin films, so that they can be implemented in electrode fabrication processes based on screen-printing and lithography techniques, respectively. We emphasize the sol-gel routes developed in our group for the synthesis of bismuth or gold nanoparticle doped porous carbon composites applied to fabricate electrochemical sensors that can be scaled down to produce miniaturized on-chip sensing devices for the sensitive detection of heavy metal pollutants in water. The trend towards the miniaturization of electrochemical sensors to be readily employed as analytical tools in environmental monitoring follow the market requirements of rapid and accurate on-site analysis, small sample consumption and waste production, as well as potential for continuous or semi-continuous in-situ determination of a wide variety of target analytes.

The Role of Polymers in the Synthesis of Noble Metal Nanoparticles: A Review

Lately, many efforts have been devoted to finding more efficient methods to prepare metal nanoparticles with controlled shapes and sizes, low polydispersity, high purity and good stability in a specific dispersion medium. Therefore, it is highly desired to develop synthetic routes that can contribute to tune the properties of metal nanoparticles for their potential applications in diverse scientific and technological fields. Thus, the application of polymers in the synthesis of metal nanoparticles has attracted great interest due to the better understanding of the parameters involved in the stabilization processes of metal nanoparticles. In addition, the use of polymers in the chemical reduction of metal ions in solution has also attracted much attention recently. Thus, this field of research is growing in importance because it would be possible, for example, to prepare hybrid nanocomposites by using non-toxic reagents and simplified synthetic routes. However, control of the shape, improvement of the size distribution and establishing correlations between polymer structure and characteristics of noble metal nanoparticles are still challenging tasks that should be considered in the synthesis processes in order to obtain hybrid nanomaterials with desirable properties.

Ionic Liquid-Assisted Synthesis and Catalytic Properties of AuPd Bimetallic Particles

Ionic liquid-assisted synthesis of inorganic materials has been demonstrated to be an efficient synthesis route in the inorganic community. Here AuPd alloy particles are successfully synthesized with the assistance of the ionic liquid 1-octyl-3-methylimidazolium chloride ([OMIM]Cl) at room temperature. The p-nitrophenol reduction reaction using the synthesized metal particles as the catalysts indicates that the synthesized Au(1)Pd(1) particles exhibit the highest catalytic activity in comparison with the studied AuPd particles, the Au and the Pd particles. Therefore, the present synthesis route could be used as an efficient synthesis strategy for fabrication of metal alloy particles with interesting catalytic properties.

Rapid and Sensitive Detection of p53 Based on DNA-Protein Binding Interactions Using Silver Nanoparticle Films and Microwave Heating

Tumor detection can be carried out via the detection of proteins, such as p53, which is known to play vital role in more than 50% of all cancers affecting humans. Early diagnosis of tumor detection can be achieved by decreasing the lower detection limit of p53 bioassays. Microwave-accelerated bioassay (MAB) technique, which is based on the use of circular bioassay platforms in combination with microwave heating, is employed for the rapid and sensitive detection of p53 protein. Direct sandwich ELISA was constructed on our circular bioassay platforms based on DNA-protein binding interactions. Colorimetric and fluorescence based detection methods were used for room temperature bioassay (control bioassay; total bioassay time is 27 hours) and bioassay using microwave heating (i.e., the MAB technique; total bioassay time is 10 minutes). In the colorimetric based detection, a very high background signal due to the non-specific binding of proteins for the bioassay carried out at room temperature and a LLOD of 0.01 ng/mL for p53 was observed using the MAB technique. The LLOD for the fluorescence-based detection using the MAB technique was found to be 0.01 ng/mL. The use of circular bioassay platforms in the MAB technique results in microwave-induced temperature gradient, where the specific protein binding interactions are significantly accelerated; thereby reducing the background signal and the lower limit of detection of p53 protein.