The past decade has witnessed a phenomenal rise in nanotechnology research due to its broad range of applications in diverse fields including food safety, transportation, sustainable energy, environmental science, catalysis, and medicine. The distinctive properties of nanomaterials (nano-sized particles in the range of 1 to 100 nm) make them uniquely suitable for such wide range of functions. The nanoparticles when manufactured using green synthesis methods are especially desirable being devoid of harsh operating conditions (high temperature and pressure), hazardous chemicals, or addition of external stabilizing or capping agents. Numerous plants and microorganisms are being experimented upon for an eco–friendly, cost–effective, and biologically safe process optimization. This review provides a comprehensive overview on the green synthesis of metallic NPs using plants and microorganisms, factors affecting the synthesis, and characterization of synthesized NPs. The potential applications of metal NPs in various sectors have also been highlighted along with the major challenges involved with respect to toxicity and translational research.

Green Synthesis of Metallic Nanoparticles: Applications and Limitations

The sustainable growth of any society is in direct proportion with developing novel methods and technologies for the management of its environmental quality. The use of Magnetic Nanoparticles (MNPs) has emerged as an efficient tool for remediation of wastewater owing to its intrinsic qualities including size, surface effect, quantum effect, etc. These intrinsic properties of MNPs have diversified their application in managing the qualitative stress on water resources. The present review aims to assess the use of MNPs in removing organic and inorganic contaminants from wastewater. Insights into various synthesis methods and their effects on contaminant removal are also presented. It is reported that MNPs provide target specificity and cost-effectiveness as compared to conventional treatment methods. Moreover, the biological synthesis of MNPs is proven to be eco-friendly and aids in sustainable development. Nearly 100% removal of various types of contaminants such as pharmaceuticals and personal care products, dyes, pesticides, heavy metals, etc. can be achieved through MNPs. Some MNPs have shown a magnetic saturation reaching up to 70 emu/g, and recycling up to 5 cycles with >95% removal efficiency. High pollutant removal efficiency (>98%) can also be achieved in a short time (within 5 min) by MNPs. It is noteworthy that, nanosorption along with the redox reactions are the most frequently used and efficient mechanisms of contaminant removal from wastewater samples.

Synthesis and characterization of magnetic nanoparticles, and their applications in wastewater treatment: A review

Recent developments in nanoscience have appreciably modified how diseases are prevented, diagnosed, and treated. Metal nanoparticles, specifically silver nanoparticles (AgNPs), are widely used in bioscience. From time to time, various synthetic methods for the synthesis of AgNPs are reported, i.e., physical, chemical, and photochemical ones. However, among these, most are expensive and not eco-friendly. The physicochemical parameters such as temperature, use of a dispersing agent, surfactant, and others greatly influence the quality and quantity of the synthesized NPs and ultimately affect the material’s properties. Scientists worldwide are trying to synthesize NPs and are devising methods that are easy to apply, eco-friendly, and economical. Among such strategies is the biogenic method, where plants are used as the source of reducing and capping agents. In this review, we intend to debate different strategies of AgNP synthesis. Although, different preparation strategies are in use to synthesize AgNPs such as electron irradiation, optical device ablation, chemical reduction, organic procedures, and photochemical methods. However, biogenic processes are preferably used, as they are environment-friendly and economical. The review covers a comprehensive discussion on the biological activities of AgNPs, such as antimicrobial, anticancer anti-inflammatory, and anti-angiogenic potentials of AgNPs. The use of AgNPs in water treatment and disinfection has also been discussed in detail.

A Review on Silver Nanoparticles: Classification, Various Methods of Synthesis, and Their Potential Roles in Biomedical Applications and Water Treatment

In the last three decades, pharmaceutical research has increased tremendously to offer safe and healthy life. However, the high consumption of these harmful drugs has risen devastating impact on ecosystems. Therefore, it is worldwide paramount concern to effectively clean pharmaceuticals contaminated water streams to ensure safer environment and healthier life. Nanotechnology enables to produce new, high-technical material, such as membranes, adsorbent, nano-catalysts, functional surfaces, coverages and reagents for more effective water and wastewater cleanup processes. Nevertheless, nano-sorbent materials are regarded the most appropriate treatment technology for water and wastewater because of their facile application and a large number of adsorbents. Several conventional techniques have been operational for domestic wastewater treatment but are inefficient for pharmaceuticals removal. Alternatively, adsorption techniques have played a pivotal role in water and wastewater treatment for a long, but their rise in attraction is proportional with the continuous emergence of new micropollutants in the aquatic environment and new discoveries of sustainable and low-cost adsorbents. Recently, advancements in adsorption technique for wastewater treatment through nanoadsorbents has greatly increased due to its low production cost, sustainability, better physicochemical properties and high removal performance for pharmaceuticals. Herein, this review critically evaluates the performance of sustainable green nanoadsorbent for the remediation of pharmaceutical pollutants from water. The influential sorption parameters and interaction mechanism are also discussed. Moreover, the future prospects of nanoadsorbents for the remediation of pharmaceuticals are also presented. 

Sustainable green nanoadsorbents for remediation of pharmaceuticals from water and wastewater: A critical review

Sustainable green nanoadsorbents for remediation of pharmaceuticals from water and wastewater: A critical review.

Adsorption of organic pollutants, toxic metal ions, and removal of harmful bacteria can give us clean and pure drinkable water from wastewater resources. Respective magnetite nanoparticles (MNPs) were synthesized using a cheaper and greener way in an open-air environment with the use of crude latex of Jatropha curcas (JC) and leaf extract of Cinnamomum tamala (CT). Characterization of MNPs had been performed by dynamic light scattering (DLS), Ultraviolet-visible (UV-vis) spectroscopy, Fourier-transform infrared (FTIR) spectroscopy, powdered X-ray diffraction (XRD), and field emission scanning electron microscope (FE-SEM). The size ranges of the synthesized MNPs were observed in between 20–42 nm for JC-Fe3O4 and within 26–35 nm for CT-Fe3O4 by FE-SEM images. The effect of synthesized magnetic nanoparticles in wastewater treatment (bacterial portion), dye adsorption, toxic metal removal as well as antibacterial, antioxidant, and cytotoxic activities were studied. This purification will lead to an increase in the resources of pure drinking water in the future.

Tae Wan Kim

Papers

Green Synthesis, Characterization and Application of Natural Product Coated Magnetite Nanoparticles for Wastewater Treatment

Preparation of a Camptothecin‐conjugated Molecular Carrier and its Cytotoxic Effect Toward Human Colorectal Carcinoma In Vitro

Intracellular delivery of oxaliplatin conjugate via cell penetrating peptide for the treatment of colorectal carcinoma in vitro and in vivo.