Green Synthesis Methods

Nanotechnology becomes the most interesting area for researchers from last two decades. There are several methods to synthesis nanoparticles but the use of green method for synthesis reduces or eliminates the generation of hazardous byproducts. Green synthesis method is environment friendly alternative to conventional synthesis techniques. Green chemistry is about reducing risk, energy, environmental impact, hazard, cost, materials and waste. The green method or biological method involves the use of microorganisms, plants etc. for synthesis of nanoparticles. In our present research work we use Murraya koenigii leaves powder extract as reducing and capping agent. Plant sources containing the phytoconstituents viz., Tannins, Alkaloids, Polyphenols, Flavonoids, Citric acid etc. Metallic and metal oxides nanoparticles of various shapes, sizes, contents and physicochemical properties can be synthesized using green synthesis method. The synthesized Iron oxide Nanoparticles were characterized be different analytical techniques. The surface morphology revealed by SEM, elemental composition by EDX, Different functional groups revealed by FTIR spectroscopy and particle size measured by particle size analyzer.

Background: Brain cancer is one of the types of cancer that appears with the growth of cancer cells in the brain. In this experimental study, we investigated and compared the effect of cerium oxide nanoparticles synthesized by the green method from Aloe vera with urolithin B on U87MG cancer cells. Materials and Methods: Cerium oxide nanoparticles were produced by the green synthesis method from the Aloe vera plant and confirmed by nanoparticle size characterization tests and an FESEM microscope. The U87MG cells were obtained from Pasteur Institute of Tehran, Iran, and after passage, they were treated with cerium oxide nanoparticles and urolithin B drug for 72 h and cell colonies for 15 days. Results: The IC50 of cancer cells in the MTT test for urolithin B and cerium oxide nanoparticles synthesized by green method from Aloe vera plant with urolithin B were 170 μM and 135 μM, respectively. In addition, the survival percentage results from the clonogenic test at a concentration of 30 μM for cerium oxide nanoparticles (78%), urolithin B(61%), and cerium oxide nanoparticles with urolithin B(30%), and for a concentration of 60 μM, it was 60, 42, and 16%, respectively. Conclusion: Urolithin B has a higher cytotoxic effect (170μM) than cerium oxide nanoparticles synthesized by the green method from the Aloe vera plant, and when combined with cerium oxide nanoparticles, this cytotoxic effect increased more (135μM). It also reduced the survival percentage of colonies within 15 days of treatment.

The Green synthesis method is an attractive approach to producing nanoparticles due to its environmentally friendly nature and its ability to provide the same quality as conventional ZnO. Zinc oxide nanoparticles (ZnO NPs) were successfully synthesized using garlic (Allium sativum) bulb extract as a reducing agent using the green synthesis method. XRD results showed that the ZnO crystals formed were hexagonal wurtzite, with crystallite sizes of 30.84 and 42.5 nm for ZnO-G10 and ZnO-G20 samples. FTIR results showed the presence of typical ZnO absorption in the region around 440-480 cm−1. The photodegradation of congo red dye was further studied, and the maximum degradation efficiency reached 99.0% for 120 minutes. These results indicate the potential of ZnO material synthesized by the green synthesis method for photocatalyst applications.

Green synthesis, characterization and bioactivity of biogenic zinc oxide nanoparticles

Superparamagnetic properties of iron oxide nanoparticles using vitex negundo leaf extract by green synthesis method and its antimicrobial activity against wound pathogen

Silver nanoparticles (AgNPs) have garnered attention due to their antimicrobial properties and applications in nanomaterials. The objective of this study is to compare the antimicrobial activities of AgNPs synthesized using green and traditional methods with silver ions (Ag+). The characterization of AgNPs was conducted through the utilization of UV-Vis spectroscopy, energy-dispersive X-ray spectrometry, transmission electron microscopy, X-ray diffraction, and differential pulse voltammetry (DPV). AgNPs presented quasi-spherical nature and well-dispersed characteristics, with a mean diameter around 10nm and 25nm for the traditional and green methods respectively. DPV measurements showed a decline of the area under the curve from 1.79 μA mm-2 to 0.7679 μA mm-2, indicating limited colloidal stability of green AgNPs. In contrast, traditional AgNPs demonstrated stability over time, maintaining an area under the curve of around 31 μA mm-2 over a 30-day period. The antimicrobial efficacy against Staphylococcus aureus and Escherichia coli was assessed via the broth dilution method. The results indicated that there were similar minimum inhibitory concentrations and minimal bactericidal concentrations (MIC and MBC) for both nanoparticle types and Ag+ against S. aureus (≈ 1 mM). While differences were detected against E. coli: traditional AgNPs evidenced lower MIC and MBC values on day 30 (≈ 0.5 mM) and Ag+ evidenced MIC and MBC values of 0.5 and 0.75 mM on both days 1 and 30. Green AgNPs exhibited heightened antimicrobial activity over time, as evidenced by the planktonic growth of S. aureus and E. coli in days 1 and 30. This observation is concomitant with an increase in Ag⁺ release evidenced by DPV, underscoring the key role of silver ions in mediating antibacterial effects. This research contributes to a more comprehensive understanding of how synthesis method, nanoparticle stability, silver ion release, and testing methodology influence the antimicrobial performance of AgNPs, offering insights critical for their practical application.

Metal oxide nanoparticles have found their own inevitable place in the field of Metal oxide nanoparticles have found their own inevitable place in the field of nanotechnology due to their versatile applications like catalysis, drug delivery, sensors, energy devices, semiconductors, food technology, agriculture and medicine. The use of green synthesis techniques is becoming more and more significant as a practical means of producing nanoparticles that are less hazardous to the environment. It is hopeful for large-scale commercial production because green synthesis methods can yield nanomaterials with lower production costs and energy inputs than conventional synthesis methods. To attain this, plant extracts can be used as precipitating agents for the preparation of metal oxides, by this we can eliminate the usage of hazardous chemicals. Phytochemicals, which are active substances obtained from plants used as reducing and stabilizing agents in the ecologically benign manufacturing of nanoparticles. Furthermore, a cutting-edge green synthesis method that has garnered a lot of scholarly attention is the creation of metal and metal-based hybrid nanoparticles utilizing plants or plant extracts. In this review article we mainly, summarized the synthesis of various metal oxides include zinc oxides, cobalt oxides, iron oxides, magnesium oxides and other nano particles using the plant extract via green synthetic methods and we discussed about some biological applications of these metal oxides. HIGHLIGHTS Metal oxide nanoparticles have found their own inevitable place in the field of nanotechnology due to their unique properties. Green synthesis techniques and the synthesized metal oxide nanoparticles is becoming more and more significant because of less hazardous to the environment. Plant extracts can be used as precipitating agents for the preparation of metal oxides, by this we can eliminate the usage of hazardous chemicals. Phytochemicals, which are active substances obtained from plants used as reducing and stabilizing agents in the ecologically benign manufacturing of nanoparticles. GRAPHICAL ABSTRACT

The purpose of this study was to evaluate the economic feasibility of producing copper oxide (CuO) nanoparticles using the green synthesis method on an industrial scale for 10 years by evaluating from an engineering and economic perspective. Various economic parameters are used to analyze economic viability, including Gross Profit Margin (GPM), Cumulative Net Present Value (CNPV), Payback Period (PBP), as well as economic variations in sales, taxes, raw materials, labor wages, and utilities to ensure project feasibility. Technical analysis to produce 100 kg of CuO nanoparticles per day requires a total production cost of 220,322.850.00 IDR and the gross profit margin is 16,721,250.000,00 IDR per year. PBP analysis shows that the investment will be profitable after more than three years. This project can compete with PBP capital market standards because of the short investment return. The profit is relatively economical, so this project can be run for 10 years under ideal conditions. This research is expected to be a reference for technical and economic analysis of industrial-scale production of CuO nanoparticles

In this study, it was aimed to remove Congo Red (CR) dye in aqueous solution by biosynthesized Selenium Nanoparticles from Prunus armeniaca L. ( PA L‐SeNPs) leaf wastes by green synthesis method. The characteristic structure of PA L‐SeNPs was determined by UV‐vis spectroscopy, X‐ray diffraction (XRD), Brunauer–Emmett–Teller (BET), scanning electron microscope (SEM), energy dispersive X‐ray (EDX), fourier transform infrared spectroscopy (FTIR), thermogravimetry‐differential thermal analysis (TGA‐DTA), dynamic light scattering (DLS), zetasizer, and point of zero charge (pH pzc ). The effects of pH, adsorbent amount, time, initial concentration, and temperature were investigated by batch adsorption studies. 2 different kinetic and 4 isotherm models were tested and error analysis functions were determined for the most suitable model. Accordingly, the particle size, crystallinity, pH pzc value and average surface charge of PA L‐SeNPs were determined as 9.969 nm, 48.50 %, 3.47, and −23.6 mV, respectively. Also, the most suitable kinetic and isotherm models for the removal of CR dye with PA L‐SeNPs were found as Pseudo‐second‐order and Freundlich, with R 2 values of 0.996, respectively. Also, where the optimum pH was 7.00, the maximum adsorption capacity was calculated as 96.59 mgCR/g PA L‐SeNPs. The results obtained show that environmentally friendly and low‐cost PA L‐SeNPs produced by the green synthesis method are a suitable alternative for the removal of CR dye.

Simultaneous and rapid determination of polycyclic aromatic hydrocarbons by facile and green synthesis of silver nanoparticles as effective SERS substrate.

Fungal infections are a growing concern worldwide, necessitating the development of novel, sustainable antifungal agents. This review focuses on green synthesis of antifungal agents using plant extracts, highlighting their potential, efficacy, and applications. Fungal infections pose a significant threat to human health, necessitating the development of novel, eco-friendly antifungal agents. This review focuses on green synthesis of antifungal agents using plant extracts from Dragon Fruit (Hylocereus polyrhizus) and Tridax procumbens. Phytochemical constituents, such as flavonoids, phenolic acids, and betacyanins, exhibit potent antifungal activity against Candida, Aspergillus, and Fusarium. Dragon Fruit extract inhibits fungal growth by 80-90%. Tridax procumbens extract exhibits MIC values of 0.5-2.0 mg/mL against Candida spp. green synthesis methods (solvent-free, ultrasound-assisted) enhance antifungal activity. Plant extracts from Dragon Fruit and Tridax procumbens offer a sustainable, eco-friendly approach to developing novel antifungal agents. Green synthesis methods enhance antifungal activity, providing a promising alternative to conventional therapies.

<p indent="0mm">As a type of zeolite with high catalytic activity and high stability, nano ZSM-5 plays an important role in various fields of industry. However, a large amount of expensive and non-recyclable organic templates, as well as the high energy consumption caused by long-term crystallization, limit the application of nano ZSM-5 and cause environmental pollution. In addition, high temperature leads to excessive pressure in autoclave, posing safety hazard. Therefore, developing green synthesis strategies for nano ZSM-5 zeolite is of great significance. In this review, green synthesis methods of nano ZSM-5 in recent years are systematically described based on “green chemistry” principles. The advantages and limitations of different green synthesis methods are compared, and their development directions are prospected.

In this analysis, A green synthesis method utilizing a plant extract derived from Rumex nepalensis (spreng) was employed to synthesize silver nanoparticles. The synthesized nanoparticles were thoroughly characterized for their structural, surface morphological, optical, antioxidant, and antibacterial properties. Structural analysis revealed a face-centered cubic structure, while FTIR analysis confirmed the presence of biosurfactant molecules in the leaf extract that acted as reducing agents. SEM and TEM analyses further confirmed the spherical shape of the nanoparticles, with a size range of 19-28 nm. The evaluation of the silver nanoparticles demonstrated their antioxidant and antibacterial properties. These nanoparticles exhibited activities in both antioxidant and antimicrobial realms, showcasing their potential as dual-functional agents. This study highlights the effectiveness of the green synthesis method using Rumex nepalensis (spreng) extract for the production of silver nanoparticles with desirable properties for various applications.

Signifcant challenges for the modern international community are population growth and climate change, and the latest technologies are helping to solve them. These include nanotechnologies that are capable of positively influencing the quality of agricultural products, minimising the negative impact of pesticides on the environment and human health, and increasing production productivity and food safety. Nanotechnology helps to minimise waste by producing more efcient products, leading to the development of precision agriculture and efcient resource management. Minimising the production of hazardous substances, reducing energy consumption in green nanotechnology and almost no toxic chemicals make green nanomaterials widely used and desirable in various felds of human activity. Traditional and new methods for the formation of nanosized materials are considered, with an emphasis on their advantages and disadvantages. Extra- and intracellular ways of nanoparticle formation, as well as ascending and descending methods are described. The aim of the work was to establish the possibility of green synthesis of CuO nanoparticles using peppermint and lemon balm extracts. The plant extracts were prepared by ethanol extraction from the leaves in an extractor. The extract was separated from the plant material by fltering through flter paper. Copper nanoparticles were synthesised by the reduction of copper sulphate in the presence of peppermint or lemon balm extract, which acted as both a reducing agent and a nanoparticle stabiliser. The paper shows the possibility of synthesising copper oxide nanoparticles by the method using peppermint (Mentha piperita) and lemon (Melissa ofcinalis L.) balm leaf extracts. The TEM morphological study of Cu0 metal nanoparticles in the volume of polymeric nanocomposites and those created by the green synthesis method showed that the average size of copper (Cu0) nanoparticles is 3.5 and 12.2 nm, respectively. It was found that the thermo-chemical method of creating nanocomposites is cheap and accessible, but causes the formation of small metal nanoparticles, in contrast to the polymeric nanocomposite created by the green synthesis method, which is environmentally friendly and occurs at low temperatures. Key words: nanobiotechnology, nanoparticles, environmentally friendly products, nanoparticles, copper oxide, silver particles.

Green synthesized zinc oxide nanostructures and their applications in dye-sensitized solar cells and photocatalysis: A review