Green Nanotechnology

Recent advances in gene delivery nanoplatforms based on spherical nucleic acids

Gene therapy is a therapeutic option for mitigating diseases that do not respond well to pharmacological therapy. This type of therapy allows for correcting altered and defective genes by transferring nucleic acids to target cells. Notably, achieving a desirable outcome is possible by successfully delivering genetic materials into the cell. In-vivo gene transfer strategies use two major classes of vectors, namely viral and nonviral. Both of these systems have distinct pros and cons, and the choice of a delivery system depends on therapeutic objectives and other considerations. Safe and efficient gene transfer is the main feature of any delivery system. Spherical nucleic acids (SNAs) are nanotechnology-based gene delivery systems (i.e., non-viral vectors). They are three-dimensional structures consisting of a hollow or solid spherical core nanoparticle that is functionalized with a dense and highly organized layer of oligonucleotides. The unique structural features of SNAs confer them a high potency in internalization into various types of tissue and cells, a high stability against nucleases, and efficay in penetrating through various biological barriers (such as the skin, blood-brain barrier, and blood-tumor barrier). SNAs also show negligible toxicity and trigger minimal immune response reactions. During the last two decades, all these favorable physicochemical and biological attributes have made them attractive vehicles for drug and nucleic acid delivery. This article discusses the unique structural properties, types of SNAs, and also optimization mechanisms of SNAs. We also focus on recent advances in the synthesis of gene delivery nanoplatforms based on the SNAs.

Phyto-synthesized silver nanoparticles from Sargassum subrepandum: anticancer, antimicrobial, and molluscicidal activities

In the realm of nanotechnology, the use of algae to produce nanoparticles is an environmentally friendly, sustainable, and economically viable strategy. In the present study, the brown macroalgae Sargassum subrepandum was utilized to effectively produce silver nanoparticles (AgNPs). Through various characterization techniques, the AgNPs' structural integrity was confirmed. AgNPs exhibited significant antimicrobial activity against Pseudomonas aeruginosa and Fusarium equiseti. AgNPs showed cytotoxic effects on the MCF-7 breast adenocarcinoma cell line with an IC50 of 12.5 µg/ml. Treatment with AgNPs resulted in a marked reduction in cell viability, alongside evident apoptotic and necrotic morphological changes in the cancer cells. Through molecular docking studies, a deeper understanding of the interaction between AgNPs and crucial proteins related to cancer has been achieved, AgNPs showed a promising molluscicidal action on Biomphalaria alexandrina snails, a Schistosoma mansoni intermediate host. The half-lethal dose (LC50) of AgNPs was determined to be 0.84 mg/L. The potential consequences of its administration include potential disruptions to the glycolysis profile, as well as potential impacts on the steroidal hormone's estrogen and testosterone and certain kidney function tests. This study highlights the diverse uses of algae-synthesized AgNPs, ranging from healthcare to environmental management, demonstrating their importance in advancing nano-biotechnological solutions.

Alkaline protease based hydrothermal synthesis of novel Pd/CuO/ZnO nanocomposite: A new entry into photocatalytic and biomedical applications

Here, we reported the process for the production of Pd/CuO/ZnO nanocomposite utilizing alkaline protease from Phalaris minor seed extract, which is a unique, effective biogenic approach. Alkaline protease performed a crucial part in the reduction, capping and stabilization of Pd/CuO/ZnO nanocomposites. A series of physicochemical techniques were used to inquire the formation, size, shape and crystalline nature of Pd/CuO/ZnO nanocomposites. The notable performance of the synthesized nanocomposite as a photocatalyst and an antibacterial disinfectant was astonishing. The Pd/CuO/ZnO nanocrystals showed considerable photocatalytic activity by eliminating 99 % of the methylene blue (MB) in <30 min of exposure. After three test cycles, the nanocatalyst demonstrated exceptional reliability as a photocatalyst. The nanocomposite was also discovered to be an effective antibacterial agent, with zones of inhibitory activity for Staphylococcus aureus and Escherichia coli bacteria of 30(±0.2), 27(±0.3), 22(±0.2), and 21(±0.3) mm, respectively, in both light and dark conditions. Moreover, the Pd/CuO/ZnO nanocomposites showed strong antioxidant activity by efficiently scavenging 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals. The photocatalytic, antibacterial and antioxidative performance of Pd, CuO, ZnO, and CuO/ZnO were also assessed for the sake of comparison. This work shows that biogenic nanocomposites may be employed as a feasible alternative photocatalyst for the decomposition of dyes in waste water as well as a sustainable antibacterial agent.

Porous α-Fe2O3 nanocarriers: Biosynthesis and in vitro gene delivery applications

Non-viral gene delivery is a new therapeutic in the treating genetic disorders. The most important challenge in nonviral gene transformation is the immunogenicity of carriers. Nowadays, The immunogenicity of nanocarriers as a deliverer of nucleic acid molecules has received significant attention. In this research, hematite green nanocarriers were prepared in one step with rosemary extract. Synthetic nanocarriers were investigated by using XRD (X-ray diffraction analysis), FESEM-EDX (field emission scanning electron microscopy with energy dispersive X-Ray spectroscopy), HR-TEM (high-resolution transmission electron microscopy), VSM (value stream mapping), TGA- DTG (thermal gravimetric analysis-differential thermal analysis), FT-IR (fourier-transform infrared spectroscopy), BET (brunauer-emmett-teller) and BJH (barrett-joyner-halenda) analyses. The cytotoxicity of synthetic nanocarriers was evaluated on HEK-293Tcell lines at concentration of 1-500 μg/ml using MTT method. Finally, targeted transfection of GFP plasmid using green porous particles was performed using an external magnetic field. Biogenic hematite nanoparticles with hexagonal crystal structures have a 3D pile flower-like morphology. The existence of rosemary phytochemicals in the construction of nanoparticles has caused minimal toxicity and high biocompatibility of nanocarriers. Also, TGA studies confirmed the stability of bionic nanoparticles. Superparamagnetic green nanocarriers at concentrations above 500 μg/ml is not toxic to HEK293T cells. The delivery efficiency of the plasmid was optimal at an N/P ratio of 3. Therefore, the porous α-Fe2O3 green nanocarriers are non-viral and safe carriers with potential applications in gene therapy.

Nano-elicitation and hydroponics: a synergism to enhance plant productivity and secondary metabolism

MAIN CONCLUSION

This review has explored the importance of using a synergistic approach of nano-elicitation and hydroponics to improve plant growth and metabolite production. Furthermore, it emphasizes the significance of green nanotechnology and eco-friendly practices while utilizing this approach to promote the development of a sustainable agriculture system. Nano-elicitation stimulates metabolic processes in plants using nanoparticles (NPs) as elicitors. The stimulation of these biochemical processes can enhance plant yield and productivity, along with the production of secondary metabolites. Nanoparticles have garnered the attention of scientific community because of their unique characteristics, such as incredibly small size and large surface-to-volume ratio, which make them effective elicitors. Hydroponic systems, which optimize growing conditions to increase plant production, are typically used to study the effect of elicitors. By integrating these two approaches, the qualitative and quantitative output of plants can be increased while employing minimal resources. As the global demand for high-quality crops and bioactive compounds surges, embracing this synergistic approach alongside sustainable farming practices can pave the way for resilient agricultural systems, ensuring food security and fostering an eco-friendly environment.

Polysaccharide mediated nanodrug delivery: A review

Polysaccharides have drawn a lot of attention due to their potential as carriers for drugs and other bioactive chemicals. In drug delivery systems, natural macromolecules such as polysaccharides are widely utilized as polymers. This utilization extends to various polysaccharides employed in the development of nanoparticles for medicinal administration, with the goal of enhancing therapeutic efficacy while minimizing side effects. This study not only offers an overview of the existing challenges faced by these materials but also provides detailed information on key polysaccharides expertly engineered into nanoparticles. Noteworthy examples include Bael Fruit Gum, Guar Gum, Pectin, Agar, Cellulose, Alginate, Chitin, and Gum Acacia, each selected for their distinctive properties and strategically integrated into nanoparticles. The exploration of these natural macromolecules illuminates their diverse applications and underscores their potential as effective carriers in drug delivery systems. By delving into the unique attributes of each polysaccharide, this review aims to contribute valuable insights to the ongoing advancements in nanomedicine and pharmaceutical technologies. The overarching objective of this review research is to assess the utilization and comprehension of polysaccharides in nanoapplications, further striving to promote their continued integration in contemporary therapeutics and industrial practices.

Anti-Bacterial Activity of Green Synthesised Silver and Zinc Oxide Nanoparticles against Propionibacterium acnes

Propionibacterium acnes plays a critical role in the development of acne vulgaris. There has been a rise in the number of patients carrying P. acnes strains that are resistant to antibiotics. Thus, alternative anti-microbial agents are required. Zinc oxide (ZnO-NPs) and silver (Ag-NPs) nanoparticles can be used against several antibiotic-resistant bacteria. The impact of Ag-NPs and ZnO-NPs against two clinical strains of P. acnes, P1 and P2, and a reference strain, NCTC747, were investigated in this research. A chemical approach for the green synthesis of Ag-NPs and ZnO-NPs from Peganum harmala was employed. The microtiter plate method was used to examine the effects of NPs on bacterial growth, biofilm development, and biofilm eradication. A broth microdilution process was performed in order to determine minimal inhibitory (MIC) concentrations. Ag-NPs and ZnO-NPs had a spherical shape and average dimensions of 10 and 50 nm, respectively. MIC values for all P. acnes strains for Ag-NPs and ZnO-NPs were 125 µg/mL and 250 µg/mL, respectively. Ag-NP and ZnO-NP concentrations of 3.9- 62.5 µg/mL and 15-62.5 µg/mL significantly inhibited the growth and biofilm formation of all P. acnes strains, respectively. ZnO-NP concentrations of 15-62.5 μg/mL significantly inhibited the growth of NCTC747 and P2 strains. The growth of P1 was impacted by concentrations of 31.25 μg/mL and 62.5 μg/mL. Biofilm formation in the NCTC747 strain was diminished by a ZnO-NP concentration of 15 μg/mL. The clinical strains of P. acnes were only affected by ZnO-NP titres of more than 31.25 μg/mL. Established P. acne biofilm biomass was significantly reduced in all strains at a Ag-NP and ZnO-NP concentration of 62.5 µg/mL. The findings demonstrated that Ag-NPs and ZnO-NPs exert an anti-bacterial effect against P. acnes. Further research is required to determine their potential utility as a treatment option for acne.

Development of solid lipid nanoparticles-loaded drugs in parasitic diseases

Parasites cause illnesses with broad spectrum of symptoms from mild to severe, and are responsible for a significant number of outbreaks in the world. Current anti-parasitic drugs are toxic and have significant side effects. Nano-carriers are believed to obviate the limitations of conventional drugs via decreasing side effects and increasing target delivery and drug permeability with a controlled prolonged release of a drug. Solid lipid nanoparticles (SLNs) are lipid nanoparticles (LNPs), which have frequently been practiced. Suitable release rate, stability, and target delivery make SLNs a good alternative for colloidal carriers. SLNs are supposed to have great potential to deliver natural products with anti-parasitic properties. Nanoparticles have employed to improve stability and capacity loading of SLNs, during recent years. This review describes development of SLNs, the methods of preparation, characterization, and loaded drugs into SLNs in parasitic diseases. In addition, we summarize recent development in anti-parasitic SLNs-loaded drugs.

Exploring the potential of polysaccharide-based hybrid hydrogel systems for their biomedical and therapeutic applications: A review

Hydrogels are a versatile category of biomaterials that have been widely applied in the fields of biomedicine for the last several decades. The three-dimensional polymeric crosslinked hydrophilic structures of the hydrogel can proficiently hold drugs, nanoparticles, and cells, making them a potential delivery system. However, disadvantages like low mechanical strength, poor biocompatibility, and unusual in-vivo biodegradation are associated with conventional hydrogels. To overcome these hurdles, hybrid hydrogels are designed using two or more structurally different polymeric units. Polysaccharides, characterized by their innate biocompatibility, biodegradability, and abundance, establish an ideal foundation for the development of these hybrid hydrogels. This review aims to discuss the studies that have utilized naturally occurring polysaccharides to prepare hybrid systems, which were aimed for various biomedical applications such as tissue engineering, bone and cartilage regeneration, wound healing, skin cancer treatment, antimicrobial therapy, osteoarthritis treatment, and drug delivery. Furthermore, this review extensively examines the properties of the employed polysaccharides within hydrogel matrices, emphasizing the advantageous characteristics that make them a preferred choice. Furthermore, the challenges associated with the commercial implementation of these systems are explored alongside an assessment of the current patent landscape.

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.

Exploring apple pectic polysaccharides: Extraction, characterization, and biological activities - A comprehensive review

Apple (Malus domestica) is a popular and ancient fruit of the Myrtaceae family. Apple fruit is well-known for its great nutritional and phytochemical content consisted of beneficial compounds such as polyphenols, polysaccharides, sterols, and organic acids. Polysaccharides extracted from different parts of the apple fruit, including the peel, pomace, or the whole fruit, have been extensively studied. Researchers have investigated the structural characteristics of these polysaccharides, such as molecular weight, type of monosaccharide unit, type of linkage and its position and arrangement. Besides this, functional properties and physicochemical and of apple polysaccharides have also been studied, along with the effects of extraction procedures, storage, and processing on cell wall polysaccharides. Various extraction techniques, including hot water extraction, enzymatic extraction, and solvent-assisted extraction, have been studied. From the findings, it was evident that apple polysaccharides are mainly composed of (1 → 3), (1 → 6): α-β-glycosidic linkage. Moreover, the apple polysaccharides were demonstrated to exhibit antioxidant, hepatoprotective, anti-cancer, hypoilipidemic, and enzyme inhibitory properties in vitro and in vivo. The potential applications of apple polysaccharides in the food, cosmetic, pharmaceutical, nutraceutical industries have also been explored in the present review. Overall, the research on apple polysaccharides highlights their significant potential as a source of biologically active compounds with various health benefits and practical applications.

Green synthesis trends and potential applications of bimetallic nanoparticles towards the sustainable development goals 2030

The world faces threats that the United Nations has classified into 17 categories with different objectives as solutions for each challenge that are enclosed in the Sustainable Development Goals (SDGs). These actions involved the widespread use of science and technology as pathways to ensure their implementation. In this regard, sustainability science seeks the research community's contribution to addressing sustainable development challenges. Specifically, nanotechnology has been recognized as a key tool to provide disruptive and effective strategies to reach the SDGs. This review proposes the application of bimetallic nanoparticle substances capable of providing possible solutions to achieve target SDG 3: good health and well-being, SDG 6: clean water and sanitation, and SDG 12: responsible consumption and production. Furthermore, the term green nanotechnology is introduced in each section to exemplify how green synthesized bimetallic nanoparticles have been used to resolve each target SDG. This review also outlines the current scenario regarding the utilization of metallic nanomaterials in the market, together with the upscaling challenges and the lack of understanding of the long-term effects and hazards to the environment regarding bimetallic nanoparticles.

Green Synthesis and Characterization of Silver Nanoparticles Using Azadirachta indica Seeds Extract: In Vitro and In Vivo Evaluation of Anti-Diabetic Activity

BACKGROUND

Diabetes mellitus (DM) is a non-communicable, life-threatening syndrome that is present all over the world. The use of eco-friendly, cost-effective, and green-synthesised nanoparticles as a medicinal therapy in the treatment of DM is an attractive option.

OBJECTIVE

In the present study, silver nanoparticles (AI-AgNPs) were biosynthesized through the green synthesis method using Azadirachta indica seed extract to evaluate their anti-diabetic potentials.

METHODS

These nanoparticles were characterized by using UV-visible spectroscopy, Fourier transform infrared spectrophotometers (FTIR), scanning electron microscopy (SEM), DLS, and X-ray diffraction (XRD). The biosynthesized AI-AgNPs and crude extracts of Azadirachta indica seeds were evaluated for anti-diabetic potentials using glucose adsorption assays, glucose uptake by yeast cells assays, and alpha-amylase inhibitory assays.

RESULTS

Al-AgNPs showed the highest activity (75 ± 1.528%), while crude extract showed (63 ± 2.5%) glucose uptake by yeast at 80 µg/mL. In the glucose adsorption assay, the highest activity of Al-AgNPs was 10.65 ± 1.58%, while crude extract showed 8.32 ± 0.258% at 30 mM, whereas in the alpha-amylase assay, Al-AgNPs exhibited the maximum activity of 73.85 ± 1.114% and crude extract 65.85 ± 2.101% at 100 µg/mL. The assay results of AI-AgNPs and crude showed substantial dose-dependent activities. Further, anti-diabetic potentials were also investigated in streptozotocin-induced diabetic mice. Mice were administered with AI-AgNPs (10 to 40 mg/kg b.w) for 30 days.

CONCLUSIONS

The results showed a considerable drop in blood sugar levels, including pancreatic and liver cell regeneration, demonstrating that AI-AgNPs have strong anti-diabetic potential.

Hazelnut (Corylus avellana L.) shells as a potential source of dietary fibre: impact of hydrothermal treatment temperature on fibre structure and degradation compounds

BACKGROUND

Hemicellulose extraction from lignocellulosic biomasses has gained interest over the years, and hydrothermal treatment is one of the most common methods employed for this purpose. This work aimed to deeply study hazelnut (Corylus avellana L.) shells as a new source of dietary fibre, evaluating the effect of hydrothermal treatment temperatures on the type and structure of fibre extracted, but also on the formation of side-products derived from lignocellulose degradation.

RESULTS

Different process temperatures led to diverse polysaccharides in the hydrothermal extract. Pectin was identified for the first time in hazelnut shells when experimenting with extraction at 125 °C, whereas at 150 °C a heterogeneous mixture of pectin, xylan, and xylo-oligosaccharides was present. The highest yield in terms of total fibre was gained at 150 and 175 °C, and then decreased again at 200 °C. Finally, more than 500 compounds from different chemical classes were putatively identified and they appeared to be present in the extracted fibre with a different distribution and relative amount, depending on the heat treatment severity. A generally high content of phenols, phenyls, oligosaccharides, dehydro-sugars, and furans was observed.

CONCLUSIONS

Modulation of the hydrothermal treatment temperature allows fibre extracts with very different compositions, and therefore different potential end uses, to be obtained from hazelnut shells. A sequential temperature-based fractionation approach, as a function of the severity of the extraction parameters, can also be considered. Nevertheless, the study of the side-compounds formed from lignocellulosic matrix degradation, as a function of the applied temperature, needs to be fully addressed for a safe introduction of the fibre extract within the food chain. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Current Overview of Metal Nanoparticles' Synthesis, Characterization, and Biomedical Applications, with a Focus on Silver and Gold Nanoparticles

Metal nanoparticles (NPs) have garnered considerable attention, due to their unique physicochemical properties, that render them promising candidates for various applications in medicine and industry. This article offers a comprehensive overview of the most recent advancements in the manufacturing, characterization, and biomedical utilization of metal NPs, with a primary focus on silver and gold NPs. Their potential as effective anticancer, anti-inflammatory, and antimicrobial agents, drug delivery systems, and imaging agents in the diagnosis and treatment of a variety of disorders is reviewed. Moreover, their translation to therapeutic settings, and the issue of their inclusion in clinical trials, are assessed in light of over 30 clinical investigations that concentrate on administering either silver or gold NPs in conditions ranging from nosocomial infections to different types of cancers. This paper aims not only to examine the biocompatibility of nanomaterials but also to emphasize potential challenges that may limit their safe integration into healthcare practices. More than 100 nanomedicines are currently on the market, which justifies ongoing study into the use of nanomaterials in medicine. Overall, the present review aims to highlight the potential of silver and gold NPs as innovative and effective therapeutics in the field of biomedicine, citing some of their most relevant current applications.

Green synthesized Ag nanoparticles stimulate gene expression and paclitaxel production in Corylus avellana cells

Synthesis of nanoparticles (NPs) through plant extracts has been suggested as an effective and nature-friendly method. Paclitaxel is one of the most valuable secondary metabolites with therapeutic uses, and hazelnut has been suggested as one of the sustainable resources for producing this metabolite. In the present study, we synthesized Ag NPs using the ethanolic extract of C. avellana leaves and were characterized using UV-visible, FTIR, XRD, EDX, DLS, SEM, and TEM analyses. In addition, we investigated the effect of green synthesized Ag (GS Ag) NPs (5 and 10 mg/L), para-aminobenzoic acid (PABA) (20 mg/L), and AgNO3 (10 mg/L) on cell viability, physiological characteristics, gene expression, and biosynthesis of secondary metabolites in hazelnut cell cultures. The results showed that 10 mg/L Ag NPs and AgNO3 significantly affected the cell viability, the content of ROS, peroxidation of lipids, antioxidant capacity, secondary metabolite production, and expression pattern of the genes involved in the taxanes biosynthesis pathway in the hazelnut cells. The cytotoxicity increased by increasing the GS Ag NPs concentration from 5 to 10 mg/L, which was associated with reduced membrane integrity and cell viability. Elicitation of the cells with 10 mg/L Ag NPs combined with 20 mg/L PABA (as a precursor) remarkably excited the expression of TAT and GGPPS genes and the production of secondary metabolites as well as paclitaxel. So that the highest expression of TAT and GGPPS genes (3.71 and 3.69) and the highest amount of taxol (230.21 μg g-1 FW) and baccatin (1025.8 μg g-1 FW) were observed in this treatment. KEY POINTS: • For the first time, we assessed and reported the molecular and physiological responses of C. avellana cells to GS Ag NPs, AgNO3, and PABA. • In hazel cells, GS Ag NPs stimulate several physiological and molecular responses. • In addition to increasing antioxidant activity, GS Ag NPs significantly increased the expression of genes involved in the paclitaxel biosynthesis pathway and the production of secondary metabolites.

Emerging Applications of Nanotechnology in Healthcare and Medicine

Knowing the beneficial aspects of nanomedicine, scientists are trying to harness the applications of nanotechnology in diagnosis, treatment, and prevention of diseases. There are also potential uses in designing medical tools and processes for the new generation of medical scientists. The main objective for conducting this research review is to gather the widespread aspects of nanomedicine under one heading and to highlight standard research practices in the medical field. Comprehensive research has been conducted to incorporate the latest data related to nanotechnology in medicine and therapeutics derived from acknowledged scientific platforms. Nanotechnology is used to conduct sensitive medical procedures. Nanotechnology is showing successful and beneficial uses in the fields of diagnostics, disease treatment, regenerative medicine, gene therapy, dentistry, oncology, aesthetics industry, drug delivery, and therapeutics. A thorough association of and cooperation between physicians, clinicians, researchers, and technologies will bring forward a future where there is a more calculated, outlined, and technically programed field of nanomedicine. Advances are being made to overcome challenges associated with the application of nanotechnology in the medical field due to the pathophysiological basis of diseases. This review highlights the multipronged aspects of nanomedicine and how nanotechnology is proving beneficial for the health industry. There is a need to minimize the health, environmental, and ethical concerns linked to nanotechnology.

Silver-Gold Alloy Nanoparticles (AgAu NPs): Photochemical Synthesis of Novel Biocompatible, Bimetallic Alloy Nanoparticles and Study of Their In Vitro Peroxidase Nanozyme Activity

Facile synthesis of metal nanoparticles with controlled physicochemical properties using environment-friendly reagents can open new avenues in biomedical applications. Nanomaterials with controlled physicochemical properties have opened new prospects for a variety of applications. In the present study, we report a single-step photochemical synthesis of ~5 nm-sized silver (Ag) and gold (Au) nanoparticles (NPs), and Ag-Au alloy nanoparticles using L-tyrosine. The physicochemical and surface properties of both monometallic and bimetallic NPs were investigated by analytical, spectroscopic, and microscopic techniques. Our results also displayed an interaction between L-tyrosine and surface atoms that leads to the formation of AgAu NPs by preventing the growth and aggregation of the NPs. This method efficiently produced monodispersed NPs, with a narrow-sized distribution and good stability in an aqueous solution. The cytotoxicity assessment performed on breast cancer cell lines (MCF-7) revealed that the biofriendly L-tyrosine-capped AgNPs, AuNPs, and bimetallic AgAu NPs were biocompatible. Interestingly, AgAu NPs have also unveiled controlled cytotoxicity, cell viability, and in vitro peroxidase nanozyme activity reliant on metal composition and surface coating.

Activating Hydrogen Evolution Reaction on Carbon Nanotube via Aryl Functionalisation: The Role of Hybrid sp2-sp3 Interface and Curvature

The hydrogen evolution reaction (HER) is a remarkable mechanism which yields the production of hydrogen through a process of water electrolysis. However, the evolution of hydrogen requires highly conductive and stable catalysts, such as the noble metal platinum (Pt). However, the problem lies in the limitations that this catalyst and others of its kind present. Due to limited availability, as well as the costs involved in acquiring such catalysts, researchers are challenged to manufacture catalysts that do not present these limitations. Carbon nanotubes (CNTs), which are nanomaterials, are known to have a wide range of applications. However, specifically, the pristine carbon nanotube is not suitable for the HER due to the binding free energy of its positive H-atoms. Hence, for the first time, we demonstrated the use of the proposed aryl-functionalised catalysts, i.e., Aryl-L@SWCNT (L = Br, CCH, Cl, CO₂CH₃, F, I, NO₂, or t-butyl), along with the effect of the sp2-sp3 hybridised interface through the density functional theory (DFT). We performed calculations of single-walled carbon nanotubes with multiple aryl functional groups. By employing the DFT calculations, we proved that the curvature of the nanotubes along with the proposed aryl-functionalised catalysts had a noteworthy effect on the performance of the HER. Our study opens the door to investigating a promising group of catalysts for sustainable hydrogen production.

Carboxymethyl cellulose nanocolloids anchored Pd(0) nanoparticles (CMC@Pd NPs): synthesis, characterization, and catalytic application in transfer hydrogenation

Herein, we report on the preparation of novel colloidal system based on carboxymethyl cellulose (CMC) and Pd nanoparticles (CMC@Pd NPs) via an ecofriendly auto-reduction process under mild conditions. In the first step, the follow-up of reduction and preparation of CMC anchored palladium nanoparticles (Pd NPs) in aqueous solution was carried out using UV-Vis spectroscopy. Thereafter, the monodispersed colloids were fully characterized by advanced analytical, structural, and morphological techniques. Based on Scherrer equation, the as-synthesized CMC@Pd NPs crystallite size was about 10.88 nm. Accordingly, the detailed microscopic study revealed CMC nanocolloids anchored uniform distribution of Pd NPs and the presence of CMC nanofilm as protective monolayer. To the best of our knowledge, the observed nanoscale properties are reported for the first time for CMC-M system. The performance of the as-synthesized CMC@Pd nanocolloids was first investigated in the reduction of 4-nitrophenol, as a model substrate, to 4-aminophenol using NaBH4 as a hydrogen source. Moreover, the catalytic reduction of various nitroarenes bearing electron withdrawing or donating substituents was carried out and monitored by UV-Vis spectroscopy. The chemo- and regioselectivity of the catalytic reduction in presence of CMC@Pd NPs were also studied. Consequently, the prepared CMC@Pd nanocolloids exhibit remarkable activity, good heterogeneity, and higher reusability and stability for the catalytic reduction reaction under mild conditions.

The efficacy of biosynthesized silver nanoparticles against Pseudomonas aeruginosa isolates from cystic fibrosis patients

The high antibiotic resistance of Pseudomonas aeruginosa (PA) makes it critical to develop alternative antimicrobial agents that are effective and affordable. One of the many applications of silver nanoparticles (Ag NPs) is their use as an antimicrobial agent against bacteria resistant to common antibiotics. The key purpose of this research was to assess the antibacterial and antibiofilm effectiveness of biosynthesized Ag NPs against six biofilm-forming clinically isolated strains of PA and one reference strain (ATCC 27853). Ag NPs were biosynthesized using a seed extract of Peganum harmala as a reducing agent. Ag NPs were characterized by Ultraviolet-visible (UV-Vis) spectroscopy and scanning transmission electron microscopy (STEM). The effect of Ag NPs on biofilm formation and eradication was examined through micro-titer plate assays, and the minimal inhibitory (MIC) and minimum bactericidal (MBC) concentrations determined. In addition, real-time polymerase chain reactions (RT-PCR) were performed to examine the effects of Ag NPs on the expression of seven PA biofilm-encoding genes (LasR, LasI, LssB, rhIR, rhII, pqsA and pqsR). The biosynthesized Ag NPs were spherically-shaped with a mean diameter of 11 nm. The MIC for each PA strain was 15.6 µg/ml, while the MBC was 31.25 µg/ml. All PA strains exposed to Ag NPs at sub-inhibitory concentrations (0.22-7.5 µg/ml) showed significant inhibitory effects on growth and biofilm formation. Biomass and biofilm metabolism were reduced dependent on Ag NP concentration. The expression of the quorum-sensing genes of all strains were significantly reduced at an Ag NP concentration of 7.5 µg/ml. The results demonstrate the extensive in-vitro antibacterial and antibiofilm performance of Ag NPs and their potential in the treatment of PA infection. It is recommended that future studies examine the possible synergy between Ag NPs and antibiotics.

Polyvinyl alcohol/citric acid/β-cyclodextrin/CuONP composite nanofibers as an effective and green absorbent for the simultaneous extraction of three antidepressant drugs in biological fluids prior to GC-FID analysis

Composite nanofibers, namely, polyvinyl alcohol (PVA), citric acid (CA), β-cyclodextrin (β-CD), and copper oxide nanoparticles (PVA/CA/β-cyclodextrin/CuO NPs), were developed as a novel, green, and efficient adsorbent in the pipette tip-micro-solid-phase extraction method (PT-µSPE), for the simultaneous extraction of three antidepressants drugs namely imipramine (IMP), citalopram (CIT), and clozapine (CLZ) in biological fluids before quantification by gas chromatography (GC-FID). Based on the obtained results from field emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy (EDX), Fourier transform infrared spectroscopy (FT-IR), and X-ray diffraction (XRD), the successful synthesis of composite nanofibers was approved. Due to the presence of β-cyclodextrins and CuO NPs rich of functional groups on their surface, the nanofibers have high extraction efficiency. Under the optimal conditions, the linear range for imipramine, citalopram, and clozapine was 0.1 to 1000.0 ng mL^-1 with a determination coefficient ≥ 0.99. The limits of detection (LODs) were in the range 0.03 to 0.15 ng mL^-1. The relative standard deviation was 4.8 to 8.7% (within-day, n = 4) and 5.1 to 9.2% (between-day, n = 3) for 3 consecutive days. In addition, excellent clean-up was achieved which is a great advantage over other sample preparation methods. Finally, the ability of the developed method to extract the target analytes from the biological samples was evaluated.

Nanoformulations for the Delivery of Dietary Anthocyanins for the Prevention and Treatment of Diabetes Mellitus and Its Complications

Diabetes mellitus (DM) is a metabolic disease characterized by abnormal blood glucose levels-hyperglycemia, caused by a lack of insulin secretion, impaired insulin action, or a combination of both. The incidence of DM is increasing, resulting in billions of dollars in annual healthcare costs worldwide. Current therapeutics aim to control hyperglycemia and reduce blood glucose levels to normal. However, most modern drugs have numerous side effects, some of which cause severe kidney and liver problems. On the other hand, natural compounds rich in anthocyanidins (cyanidin, delphinidin, malvidin, pelargonidin, peonidin, and petunidin) have also been used for the prevention and treatment of DM. However, lack of standardization, poor stability, unpleasant taste, and decreased absorption leading to low bioavailability have hindered the application of anthocyanins as therapeutics. Therefore, nanotechnology has been used for more successful delivery of these bioactive compounds. This review summarizes the potential of anthocyanins for the prevention and treatment of DM and its complications, as well as the strategies and advances in the delivery of anthocyanins using nanoformulations.

In vitro analysis of green synthesized CuO nanoparticles using Tanacetum parthenium extract for multifunctional applications

Tanacetum parthenium L. is a popular traditional medicinal plant that the role of presence of particular phytochemical compounds are still unconsidered particularly in the bio-nano researches. Here, for the first time, the green fabrication of CuO NPs using Tanacetum parthenium L. extract was performed and assessed for the antimicrobial, cytotoxicity, and dye degradation activities. Characterization of CuO NPs was done by UV-visible spectra, XRD, FT-IR, TEM, and EDX. The synthesized CuO NPs possess a crystalline nature, a functional group that resembles T. parthenium, with a spherical shape particle with an average size of 28 nm. EDX confirmed CuO NPs formation. The CuO NPs showed excellent antimicrobial activity against tested microorganisms. The cytotoxicity of CuO NPs was demonstrated the concentration-dependent inhibition of the growth against both cancer and normal cell lines. The results exhibited concentration-dependent inhibition of the growth of Hela, A 549, and MCF7 cancer cells (IC₅₀ = 65.0, 57.4, and 71.8 µg/mL, respectively), which were statistically significant comparing control cells (IC₅₀ = 226.1 µg/mL). Furthermore, we observed that CuO NPs-induced programmed cell death in the cancer cells were mediated with the downregulation of Bcl2 and upregulation of bax, caspase-3. CuO NPs were verified to be a superb catalyst as they had excellent activity for the degradation of 99.6%, 98.7%, 96.6%, and 96.6% of Congo red, methylene blue, methylene orange, and rhodamine B as industrial dyes in 3, 6.5, 6.5, and 6.5 min, respectively. Overall, the present study nominates T. parthenium as a proper bio-agent in the biosynthesis of CuO NPs with powerful catalytic and antimicrobial activities as well as a cancer treatment.

Nano-Biofertilizers Synthesis and Applications in Agroecosystems

Green chemistry and nanobiotechnology have great potential for generating new and significant products that are favorable to the environment, industry, and consumers. The nanoforms of metals and nanocomposites are more effective and efficient agents than their bulkier counterparts because of their distinctive physical, chemical, and optical properties. Green technology is a rapidly growing scientific field that has recently received attention due to its many applications. Different nanoparticle dimensions, sizes, and bioactivities will develop as a consequence of changes in the biomaterials employed for synthesis. The existing understanding of several green synthesis methods, that depend on different plant components and microorganisms for the production of nanoparticles, is summarized in the current review. Employing these materials minimizes synthesis costs while minimizing the use of hazardous chemicals and promoting “biosynthesis.” To produce metal nanoparticles efficiently, bio-reduction is influenced by the abundance of essential enzymes, proteins, and biomolecules. Rapid biosynthetic regeneration makes this characteristic sufficient for their employment in a range of situations. In this review, we explore the biosynthesis of nanomaterials and their potential in sustainable agriculture. Biosynthesized nanofertilizers, or bionanofertilizers, are a revolutionary new class of fertilizer that has been developed with the help of nanotechnology. These fertilizers offer many advantages over traditional fertilization methods and can be used to increase crop yields while reducing the environmental impact of fertilizers. Bionanofertilizer are an inexpensive way to increase plant growth and production, and to improve the use of nutrients by plants and the health of the soil. According to our survey, nanotechnology presents a wide range of prospects by offering a cutting-edge and environmentally friendly alternative in the agricultural sector.

Physicochemical and Antibacterial Properties of Alginate Films Containing Tansy (Tanacetum vulgare L.) Essential Oil

Tansy (Tanacetum vulgare) is a common plant used in folk medicine for digestive problems, fevers, and migraines; against parasites; and as an insect repellent. The active substances in essential oil are responsible for its antimicrobial and antioxidant activity. Thus, tansy essential oil (TO) was added to alginate films to fabricate materials with antioxidant and antibacterial properties for food packaging. Sodium alginate films with glycerol and TO were tested in terms of structure, mechanical, thermal, antioxidant, and antibacterial properties. The structure of the films was examined using SEM and an ATR-FTIR spectrophotometer. The addition of TO to the alginate film significantly changed the films' microstructure, making them rougher and porous. A low-intensity band at 1739 cm^-1, indicative of the presence of TO, appeared in all spectra of alginate films with TO. Moreover, the studies revealed that essential oil acted as a plasticizer, slightly reducing tensile strength from about 7 MPa to 5 MPa and increasing elongation at break from 52% to 56% for the sample with 2% TO. The alginate films enriched in TO exhibited antioxidant properties (280 μmol Trolox/100 g of the sample with 2% TO) and antibacterial activity against Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa.

Pepper-Mediated Green Synthesis of Selenium and Tellurium Nanoparticles with Antibacterial and Anticancer Potential

The production of nanoparticles for biomedical applications (namely with antimicrobial and anticancer properties) has been significantly hampered using traditional physicochemical approaches, which often produce nanostructures with poor biocompatibility properties requiring post-synthesis functionalization to implement features that such biomedical applications require. As an alternative, green nanotechnology and the synthesis of environmentally friendly nanomaterials have been gaining attention over the last few decades, using living organisms or biomolecules derived from them, as the main raw materials to produce cost-effective, environmentally friendly, and ready-to-be-used nanomaterials. In this article and building upon previous knowledge, we have designed and implemented the synthesis of selenium and tellurium nanoparticles using extracts from fresh jalapeño and habanero peppers. After characterization, in this study, the nanoparticles were tested for both their antimicrobial and anticancer features against isolates of antibiotic-resistant bacterial strains and skin cancer cell lines, respectively. The nanosystems produced nanoparticles via a fast, eco-friendly, and cost-effective method showing different antimicrobial profiles between elements. While selenium nanoparticles lacked an antimicrobial effect at the concentrations tested, those made of tellurium produced a significant antibacterial effect even at the lowest concentration tested. These effects were correlated when the nanoparticles were tested for their cytocompatibility and anticancer properties. While selenium nanoparticles were biocompatible and had a dose-dependent anticancer effect, tellurium-based nanoparticles lacked such biocompatibility while exerting a powerful anti-cancer effect. Further, this study demonstrated a suitable mechanism of action for killing bacteria and cancer cells involving reactive oxygen species (ROS) generation. In summary, this study introduces a new green nanomedicine synthesis approach to create novel selenium and tellurium nanoparticles with attractive properties for numerous biomedical applications.

Effect of Silica-Based Nanomaterials on Seed Germination and Seedling Growth of Rice (Oryza sativa L.)

The application of nanomaterials (NMs) in agriculture has become a global concern in recent years. However, studies on their effects on plants are still limited. Here, we conducted a seed germination experiment for 5 days and a hydroponics experiment for 14 days to study the effects of silicon dioxide NMs(nSiO₂) and silicon carbide NMs(nSiC) (0,10, 50, 200 mg/L) on rice (Oryza sativa L.). Bulk SiO₂ (bSiO₂) and sodium silicate (Na₂SiO₃) were used as controls. The results showed that nSiO₂ and nSiC increased the shoot length (11-37%, 6-25%) and root length (17-87%, 59-207%) of germinating seeds, respectively, compared with the control. Similarly, inter-root exposure to nSiO₂, bSiO_2, and nSiC improved the activity of aboveground catalase (10-55%, 31-34%, and 13-51%) and increased the content of trace elements magnesium, copper, and zinc, thus promoting the photosynthesis of rice. However, Na₂SiO₃ at a concentration of 200 mg/L reduced the aboveground and root biomass of rice by 27-51% and 4-17%, respectively. This may be because excess silicon not only inhibited the activity of root antioxidant enzymes but also disrupted the balance of mineral elements. This finding provides a new basis for the effect of silica-based NMs promotion on seed germination and rice growth.

Green Synthesis of Silver Nanoparticles for Preparation of Gelatin Films with Antimicrobial Activity

Silver nanoparticles were successfully synthesized using Thuja orientalis aqueous extract and AgNO₃ as a precursor. UV–Vis showed a distinct absorption peak at 424 nm attributed to silver nanoparticles due to their surface plasmon resonance. Atomic absorption analysis reflected an increase in the concentration of nanoparticles in relation to the progress of the synthesis, obtaining a peak concentration value of 15.7 mg/L at 50 min. The FTIR spectra revealed the characteristic functional groups of phytomolecules involved in the silver–ion binding process, such as R–O–H (3335 cm⁻¹⁾ O=C–OH (2314 cm⁻¹) and C—C=C (1450 cm⁻¹). At 50 min, zeta potential showed the stability of the nanoparticles with the value of −21.73 mV. TEM micrographs revealed the formation of spherical nanoparticles with an average size of about 85.77 nm. Furthermore, films incorporated with nanoparticles exhibited a Tg from 66.42 °C to 73.71 °C and Tm at 103.31 °C. Films from the G22 formulation presented excellent antibacterial properties inhibiting the growth of Staphylococcus aureus. Thuja orientalis aqueous extract could be a low-cost, eco-friendly, and efficient reducing and capping agent for the synthesis of nanometric-sized Ag particles. Gelatin films with nanoparticles are expected to have high potential as an active food packaging system.

Efficient Green Synthesis of (Fe3O4) and (NiFe2O4) Nanoparticles Using Star Anise (Illicium verum) Extract and Their Biomedical Activity against Some Cancer Cells

Magnetite Fe3O4 and spinel (2:1) and (4:1) NiFe2O4 magnetic nanoparticles (MNPs) were prepared by simple and affordable co-precipitation methods using an extract of star anise (Illicium verum) as a green reducing agent. The morphology and chemical composition of these MNPs were confirmed by field-emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, UV-visible spectroscopy, and X-ray diffraction (XRD). The synthesized magnetite Fe3O4 and spinel (2:1) and (4:1) NiFe2O4 MNPs were in the size range of 0.1-1 µm. The MNPs had irregular clustered platelets (magnetite Fe3O4) and pyramidal structures (spinel (2:1) and (4:1) NiFe2O4 NPs). The average sizes of the synthesized magnetite Fe3O4, and spinel (2:1) and (4:1) NiFe2O4 MNPs calculated using XRD analysis were 66.8, 72.5, and 72.9 nm, respectively. In addition to the characteristic absorption peaks of magnetite Fe3O4, those of spinel (2:1) and (4:1) NiFe2O4 MNPs were detected at ~300-350 nm and ~700 nm, respectively. Overall, the results of this study indicate that the synthesized magnetite Fe3O4, and spinel (2:1) and (4:1) NiFe2O4 MNPs showed high biomedical activities against liver carcinoma cells and non-small lung adenocarcinoma cells.

Mycology-Nanotechnology Interface: Applications in Medicine and Cosmetology

In today's time, nanotechnology is being utilized to develop efficient products in the cosmetic and pharmaceutical industries. The application of nanotechnology in transforming bioactive material into nanoscale products substantially improves their biocompatibility and enhances their effectiveness, even when used in lower quantities. There is a significant global market potential for these nanoparticles because of which research teams around the world are interested in the advancements in nanotechnology. These recent advances have shown that fungi can synthesize metallic nanoparticles via extra- and intracellular mechanisms. Moreover, the chemical and physical properties of novel metallic nanoparticles synthesised by fungi are improved by regulating the surface chemistry, size, and surface morphology of the nanoparticles. Compared to chemical synthesis, the green synthesis of nanoparticles offers a safe and sustainable approach for developing nanoparticles. Biosynthesised nanoparticles can potentially enhance the bioactivities of different cellular fractions, such as plant extracts, fungal extracts, and metabolites. The nanoparticles synthesised by fungi offer a wide range of applications. Recently, the biosynthesis of nanoparticles using fungi has become popular, and various ways are being explored to maximize nanoparticles synthesis. This manuscript reviews the characteristics and applications of the nanoparticles synthesised using the different taxa of fungi. The key focus is given to the applications of these nanoparticles in medicine and cosmetology.

Cyttaria hariotii E.Fisch. as a promising source of pullulan and Mn(II)-pullulan complexes for Mn-deficiency remediation in winter cereals

Pullulan, a water-soluble polysaccharide consisting of maltotriose units used in the preparation of edible films and drug delivery, is generally produced from starch by Aureobasidium pullulans (de Bary & Löwenthal) G.Arnaud fungus. In this article, the characterisation of an alternative pullulan source - the stromata of Cyttaria hariotii E.Fisch. fungus - by elemental analysis, infrared spectroscopy and thermal analysis techniques is reported. With a view to a possible valorisation of this pullulan and its derivatives as bioactive formulations in agriculture, low-molecular-weight pullulan (<7 kDa) complexes with Mn(II), suitable for the remediation of Mn-deficiencies in winter cereal by foliar application, were synthesised and characterised by mass spectrometry.

Lignin-derived (nano)materials for environmental pollution remediation: Current challenges and future perspectives

The supply of affordable drinking and sufficiently clean water for human consumption is one of the world's foremost environmental problems and a large number of scientific research works are addressing this issue Various hazardous/toxic environmental contaminants in water bodies, both inorganic and organic (specifically heavy metals and dyes), have become a serious global problem. Nowadays, extensive efforts have been made to search for novel, cost effective and practical biosorbents derived from biomass resources with special attention to value added, biomass-based renewable materials. Lignin and (nano)material adorned lignin derived entities can proficiently and cost effectively remove organic/inorganic contaminants from aqueous media. As low cost of preparation is crucial for their wide applications in water/wastewater treatment (particularly industrial water), future investigations must be devoted to refining and processing the economic viability of low cost, green lignin-derived (nano)materials. Production of functionalized lignin, lignin supported metal/metal oxide nanocomposites or hydrogels is one of the effective approaches in (nano)technology. This review outlines recent research progresses, trends/challenges and future prospects about lignin-derived (nano)materials and their sustainable applications in wastewater treatment/purification, specifically focusing on adsorption and/or catalytic reduction/(photo)degradation of a variety of pollutants.

Recent Progress on Stability and Thermo-Physical Properties of Mono and Hybrid towards Green Nanofluids

Many studies have shown the remarkable enhancement of thermo-physical properties with the addition of a small quantity of nanoparticles into conventional fluids. However, the long-term stability of the nanofluids, which plays a significant role in enhancing these properties, is hard to achieve, thus limiting the performance of the heat transfer fluids in practical applications. The present paper attempts to highlight various approaches used by researchers in improving and evaluating the stability of thermal fluids and thoroughly explores various factors that contribute to the enhancement of the thermo-physical properties of mono, hybrid, and green nanofluids. There are various methods to maintain the stability of nanofluids, but this paper particularly focuses on the sonication process, pH modification, and the use of surfactant. In addition, the common techniques to evaluate the stability of nanofluids are undertaken by using visual observation, TEM, FESEM, XRD, zeta potential analysis, and UV-Vis spectroscopy. Prior investigations revealed that the type of nanoparticle, particle volume concentration, size and shape of particles, temperature, and base fluids highly influence the thermo-physical properties of nanofluids. In conclusion, this paper summarized the findings and strategies to enhance the stability and factors affecting the thermal conductivity and dynamic viscosity of mono and hybrid of nanofluids towards green nanofluids.

Improved green biosynthesis of chitosan decorated Ag- and Co3O4-nanoparticles: A relationship between surface morphology, photocatalytic and biomedical applications

AgNPs@Chitosan and Co₃O₄-NPs@Chitosan were fabricated with Salvia hispanica. Results showed MZI values of 5 and 30 mm for Co₃O₄-NPs- and AgNPs@Chitosan against S. aureus, and 15 and 21 mm for Co₃O₄-NPs- and AgNPs@Chitosan against E. coli (24 h, 20 μg/mL), respectively. MTT assays showed up to 80% and 90%, 71% and 75%, and 91% and 94% mammalian cell viability for the green synthesized, chemically synthesized AgNPs and green synthesized AgNPs@Chitosan for HEK-293 and PC12 cells, respectively, and 70% and 71%, 59% and 62%, and 88% and 73% for the related Co₃O₄-NPs (24 h, 20 μg/mL). The photocatalytic activities showed dye degradation after 135 and 105 min for AgNPs@Chitosan and Co₃O₄-NPs@Chitosan, respectively. FESEM results showed differences in particle sizes (32 ± 3.0 nm for the AgNPs and 41 ± 3.0 nm for the Co₃O₄NPs) but AFM results showed lower roughness of the AgNPs@Chitosan (7.639 ± 0.85 nm) compared to Co₃O₄NPs@Chitosan (9.218 ± 0.93 nm), which resulted in potential biomedical applications.

Green Method Synthesised Graphene-Silver Electrochemical Nanobiosensors for Ethambutol and Pyrazinamide

A novel nanobiosensor was constructed with graphene oxide (GO) sheets coupled to pear extract-based green-synthesised silver nanoparticles (Ag-NPs) to which cytochrome P450-2D6 (CYP2D6) enzyme was attached. The biosensor was applied in the electrochemical detection of the tuberculosis (TB) treatment drugs, ethambutol (EMB) and pyrazinamide (PZA). The surface morphology of the green-synthesised nanocomposites was studied by performing High-Resolution Transmission Electron Microscopy (HR-TEM) and High-Resolution Scanning Electron Microscopy (HR-SEM). Fourier Transform Infrared Spectroscopy (FTIR) and Raman Spectroscopy were used for structural analysis, while Ultraviolet Visible (UV-Vis) Spectroscopy was used in the optical characterisation of the nanocomposite material. Electrochemical studies on glassy carbon electrode (GCE), which were done by Cyclic Voltammetry (CV), showed that the GO|Ag-NPs||GCE electrode was highly conductive, and thereby indicating its suitability as a platform for nanobiosensor development. The non-toxic and low-cost green GO|Ag-NPs|CYP2D6||GCE nanobiosensor was used to determine EMB and PZA. The very low limit of detection (LOD) values of the biosensor for EMB (0.2962 × 10−2 nM, S/N = 3) and PZA (0.897 × 10−2 nM, S/N = 3) demonstrate that the green nanobiosensor is more sensitive than other biosensors reported for EMB and PZA.