Green synthesis of biofunctionalized iron oxide nanoparticles using lagerstroemia indica: structural characterization, antioxidant potential, and corrosion inhibition efficiency Divya Kundu, Ruchi Bharti, Uma Koul, Ajay Thakur, Monika Verma, Renu Sharma, Annu Pandey Nano Express, 2026 This study reports a green, one-pot synthesis of biofunctionalized iron-oxide nanoparticles (Fe 3 O 4 / γ -Fe 2 O 3 ) using Lagerstroemia indica leaf extract as a combined reducing/capping system. X-ray diffraction confirms mixed magnetite/maghemite phases, while UV–Vis and FTIR support phytochemical surface passivation. SEM-EDX shows agglomerated nanoscale domains enriched in Fe and O; DLS and ζ-potential indicate colloidal stabilization by plant-derived polyphenols. Antioxidant activity quantified by DPPH, ABTS, and total antioxidant capacity increases with dose, achieving up to 92.9% DPPH scavenging at 200 μg ml −1 . Potentiodynamic polarization and electrochemical impedance spectroscopy in 0.5 M HCl demonstrate mixed-type inhibition with maximum efficiency of ∼75% at 200 mg l −1 , attributed to synergistic adsorption of phytochemical shells and mixed-valence Fe centers that impede charge transfer. The aqueous, additive-lean process furnishes multifunctional nanomaterials with practical antioxidant and corrosion-protection performance.
Sustainable synthesis of silver oxide nanoparticles from Lobularia maritima: a new approach to antioxidant and photocatalytic applications Uma Koul, Ruchi Bharti, Renu Sharma, Ajay Thakur, Monika Verma, Annu Pandey Nano Express, 2025 This study introduces a green and sustainable method for synthesizing silver oxide nanoparticles (Ag 2 O NPs) using Lobularia maritima extract as a natural reducing and stabilizing agent. Unlike traditional chemical and physical methods that rely on toxic reagents and high energy inputs, this eco-friendly approach is cost-effective, safer, and aligns with green chemistry principles. The synthesized Ag 2 O NPs exhibited impressive antioxidant activity, with 80 ± 0.02% 2,2′-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) and 75 ± 0.02% 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging efficiencies, comparable to those of ascorbic and gallic acids. In photocatalytic tests, they achieved 91% degradation of methylene blue under visible light within 120 min, outperforming many chemically synthesized Ag 2 O NPs. Characterization via ultraviolet-visible (UV–vis) spectroscopy, Fourier transform infrared (FTIR), scanning electron microscopy with energy dispersive x-ray analysis (SEM-EDX), dynamic light scattering (DLS), and x-ray diffraction (XRD) confirmed the high purity, stability, and controlled morphology of the samples. These findings highlight the potential of plant-based Ag 2 O NPs for real-world applications in environmental cleanup and biomedical fields. Future research can focus on scaling production and testing biocompatibility for broader industrial use.
Environmental and health impacts of air pollution: A state of art review on the strategy to control air pollution Ruchi Bharti, Ajay Thakur, Monika Verma, Renu Sharma Aip Conference Proceedings, 2025 One of our era's greatest curse is air pollution, on account of its impact on climate change and its effects on public and individual health due to increased morbidity and mortality.There are many pollutants that are significant factors in disease in humans.Particulate Matter (PM), a type of particle with a variable but extremely small diameter that enters the respiratory system through inhalation and causes respiratory and cardiovascular disorders, reproductive and central nervous system malfunction, and cancer, is one of them.Although, ozone in the stratosphere protects against ultraviolet irradiation, but at the same time, the large concentrations of ozone at ground level are damaging to the respiratory and cardiovascular systems.Further, air pollutants like nitrogen oxide, sulphur dioxide, volatile organic compounds (VOCs), dioxins, and polycyclic aromatic hydrocarbons (PAHs) when inhaled at high volumes, can cause immediate poisoning.Similarly, heavy metals like lead, when absorbed into the human body, can cause direct poisoning or chronic intoxication, depending on the level of exposure.Respiratory disorders such as Chronic Obstructive Pulmonary Disease (COPD), asthma, and bronchiolitis, as well as lung cancer, cardiovascular events, central nervous system dysfunctions, and skin diseases, are all caused by the aforementioned compounds.Last but not least, natural disasters and climate change caused by pollution have an impact on the geographical distribution of many infectious diseases.Only public awareness combined with a multidisciplinary approach by scientific specialists will be able to handle this problem; national and international institutions must address the rise of this threat and suggest long-term remedies.This study critically evaluated recent advances in physicochemical and biological technology for cutting-edge air pollution challenges, as well as prevention and treatment of interior pollutants.
Eco-friendly Synthesis and Characterization of Bioactive Iron Oxide Nanoparticles Using Tagetes erecta Leaf Extract for Antioxidant and Anti-Corrosion Application Shobhit Sharma, Ruchi Bharti, Ajay Thakur, Renu Sharma, Monika Verma Orbital, 2025 In this study, we present a sustainable and efficient approach for synthesizing bioactive iron oxide nanoparticles (FeO NPs) using Tagetes erecta leaf extract, an eco-friendly and readily available biological resource. The green synthesis method not only eliminates the need for hazardous chemicals but also leverages the plant’s bioactive compounds, which act as natural reducing and stabilizing agents. The synthesized FeO NPs were meticulously characterized through various advanced techniques, including UV-visible spectroscopy, FTIR, SEM-EDX, XRD, and DLS, confirming their formation, structural attributes, and spherical morphology. The antioxidant potential of FeO NPs was evaluated using DPPH and ABTS assays, revealing significant free radical scavenging activities, particularly in the DPPH assay with a scavenging percentage of 92.91%, comparable to standard antioxidants like ascorbic and gallic acids. Furthermore, the FeO NPs demonstrated exceptional anti-corrosion capabilities, achieving a maximum inhibition efficiency of 79.5% at a concentration of 40 mg, as verified through electrochemical impedance spectroscopy and potentiodynamic polarization methods. This was supported by weight-loss studies, which highlighted superior performance at higher concentrations. By utilizing Tagetes erecta leaves, known for their rich bioactive profile and medicinal properties, this research advances the field of green nanotechnology. It underscores the feasibility of developing multifunctional nanoparticles for applications in environmental protection, biomedicine, and industrial corrosion prevention. This work provides a promising framework for integrating sustainability into nanomaterial synthesis while enhancing their functional properties.
Synthesis and Characterization of Silver Oxide Nanoparticles Using Lemon (Citrus limon) Leaves Extract: An Eco-Friendly Approach towards the Development of Potent Bioactive Antioxidant Agent Shivani Rana, Ruchi Bharti, Ajay Thakur, Monika Verma, Renu Sharma Russian Journal of Applied Chemistry, 2025 Abstract The primary objective of this study was to employ an eco-friendly approach for the synthesis of silver oxide nanoparticles (AgO NPs) using aqueous extracts derived from lemon (Citrus limon) leaves. This method offers numerous advantages, including biocompatibility, environmental sustainability, and resilience, making it an attractive alternative to conventional synthesis techniques. The synthesized AgO NPs underwent comprehensive analysis using Fourier Transform Infrared Spectroscopy, X-Ray Diffraction, Dynamic light scattering and Scanning Electron Microscopy-Energy Dispersive X-ray Analysis. Furthermore, the antioxidant potential of the synthesized AgO NPs was evaluated using 2,2-diphenyl-1-picrylhydrazyl and 2,2-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid assays. These assays provide insights into the ability of the nanoparticles to scavenge free radicals, highlighting their potential applications in biomedical and environmental settings. Overall, the comprehensive characterization and evaluation of the synthesized AgO NPs underscore their potential as versatile nanomaterials with promising antioxidant potential, paving the way for further exploration in various fields of research and application.
Eco-Friendly Ultrasound-Assisted Synthesis and Comprehensive Analysis of Spiropyranopyrazole Derivatives: A DMAP-Catalyzed One-Pot Approach with Spectroscopic and Computational Insights Monalisa Giri, Ruchi Bharti, Ajay Thakur, Monika Verma, Renu Sharma, Ravi Bansal Current Organocatalysis, 2025 Introduction: Spiropyranopyrazole derivatives are spiro-heterocycles of pharmacologi-cal interest due to their wide-ranging bioactivities, including antimicrobial, anticancer, and anti-inflammatory properties. However, conventional synthesis approaches are often time-consuming, environmentally taxing, and involve hazardous reagents. This study aims to develop an eco-friendly, efficient synthetic route using ultrasound-assisted conditions in water with DMAP as an organocatalyst. Method: A green one-pot multicomponent reaction was employed to synthesize spiropyranopyra-zole derivatives using ethyl acetoacetate, hydrazine hydrate, isatin derivatives, and malononitrile under ultrasonic irradiation. DMAP (20 mol%), in aqueous medium, was used as a catalyst. The synthesized compounds (5a–5j) were characterized via FTIR, ¹H NMR, ¹³C NMR, and elemental analysis. Theoretical validation was performed using DFT calculations at the B3LYP/6-311+G(d,p) level. ADME predictions were conducted to assess pharmacokinetic behavior and drug-likeness. objective: The study aims to develop a green, ultrasound-assisted, one-pot synthesis of spiropyranopyrazole derivatives using 4-(Dimethylamino)pyridine (DMAP) as an organocatalyst in water. The research further investigates the structural, electronic, and pharmacokinetic properties of the synthesized compounds through spectroscopic characterization, density functional theory (DFT) calculations, and ADME (Absorption, Distribution, Metabolism, and Excretion) analysis. Results: The ultrasound-assisted protocol delivered excellent yields (90–96%) within 1 hour with-out the use of toxic solvents or chromatographic purification. Reaction optimization confirmed DMAP in water as the most effective condition. Theoretical DFT calculations supported the stabil-ity and electronic properties of the synthesized compounds. ADME studies indicated high oral bi-oavailability, good solubility, favorable lipophilicity, and compliance with major drug-likeness fil-ters for most derivatives. Discussion: The green synthetic strategy demonstrated excellent efficiency across various substi-tuted isatins, highlighting its robustness. DFT results correlated well with spectroscopic data, con-firming structural integrity and predicting potential biological interactions. ADME profiling further reinforced the therapeutic potential of the compounds. Conclusion: This study offers a sustainable, high-yielding, and rapid methodology for synthesizing spiropyranopyrazole derivatives using water as a green solvent. Combined spectroscopic, compu-tational, and pharmacokinetic evaluations establish the synthesized compounds as promising can-didates for future pharmaceutical development.
Development of fullerenes and their derivatives Ruchi Bharti, Ajay Thakur, Monika Verma, Renu Sharma, Neha Sen Handbook of Functionalized Carbon Nanostructures from Synthesis Methods to Applications, 2024
Low temperature synthesis of carbon nanostructures Ruchi Bharti, Priya Kaushik, Shivani Naik, Ajay Thakur, Monika Verma, Renu Sharma Handbook of Functionalized Carbon Nanostructures from Synthesis Methods to Applications, 2024
