Nanoparticles are ultra-small particles with at least one dimension between 1 to 100 nanometers .pptx

Nanoparticles are ultra-small particles with at least one dimension between 1 to 100 nanometers (nm). Because of their tiny size, they exhibit unique physical, chemical, and biological properties that differ from bulk materials.

1. “Reduction of Hexavalent Chromium by CuO Nanoparticles Synthesized from Catharanthus roseus Extract” Ayushi Sharma Department of Microbiology, MJP Rohilkhand University, Bareilly 48th All India Botanical Conference | NEHU Shillong, 2025Plant diversity and green biotechnology for sustainable bioeconomy

2. INTRODUCTION The Chromium Crisis: A Growing Environmental Threat Hexavalent chromium Cr(VI) is a highly toxic heavy metal contaminant arising from industrial processes including electroplating, leather tanning, and pigment manufacturing. Its presence in water bodies poses severe risks to both human health and ecosystems . Health & Environmental Impact Carcinogenic and mutagenic effects on humans Bioaccumulation in aquatic food chains DNA damage and cellular oxidative stress Disruption of ecological balance Traditional remediation methods are costly, energy-intensive, and generate toxic sludge byproducts. Eco-friendly nanotechnology offers a sustainable alternative .

3. Objectives of Research Work Green Synthesis Synthesize copper oxide nanoparticles (CuO NPs) using Catharanthus roseus leaf extract as a bio-reducing agent Reduction Efficiency Evaluate the effectiveness of CuO NPs in reducing toxic Cr(VI) to non-toxic Cr(III) in aqueous solutions Environmental Application Demonstrate a plant-based nanotechnology approach for sustainable wastewater treatment and heavy metal remediation

4. Why Catharanthus roseus? Catharanthus roseus (Madagascar periwinkle) is a medicinal plant abundant in North India, perfectly aligning with the AIBC conference theme of leveraging plant biodiversity for bioeconomy applications . Phytochemical Advantages Alkaloids & flavonoids – powerful reducing agents Phenolic compounds – provide nanoparticle stability Hydroxyl groups – facilitate metal ion reduction Readily available – cost-effective and sustainable These biomolecules act synergistically as both reducing and capping agents during nanoparticle synthesis, eliminating the need for toxic chemical reagents.

5. Experimental Methodology 01 Plant Extract Preparation Fresh C. roseus leaves collected, washed, and boiled to obtain aqueous phytochemical extract rich in bioactive compounds 02 Nanoparticle Synthesis Plant extract mixed with copper nitrate [Cu(NO₃)₂] solution under controlled conditions, resulting in CuO NP formation 03 Characterization Analysis UV-Vis spectroscopy, X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) performed 04 Chromium Reduction Testing Batch experiments conducted varying pH, nanoparticle dosage, and contact time to optimize Cr(VI) reduction efficiency

6. Leaves Flowers Stem Roots Fruits Bio reduction Metal Salt Green synthesis of Metallic NP Antimicrobial test Characterization Methodology

7. Nanoparticle Characterization Results UV-Vis Spectroscopy Characteristic absorption peak observed at 280–300 nm, confirming successful CuO nanoparticle formation and optical properties X-Ray Diffraction Sharp diffraction peaks revealed monoclinic crystalline structure of CuO, confirming phase purity and high crystallinity FTIR Analysis Identified functional groups: hydroxyl (–OH), carbonyl (C=O), and copper-oxygen (Cu–O) bonds indicating phytochemical capping SEM Imaging Spherical and quasi-spherical CuO nanoparticles observed with particle size ranging from 20–50 nm, ideal for catalytic applications

8. Chromium Reduction Performance Optimal Reaction Conditions pH range: 2–4 (acidic conditions) Contact time: 2 hours for maximum efficiency Temperature: Ambient (25°C) NP dosage: Optimized for cost-effectiveness Reduction Mechanism Surface electron transfer from CuO nanoparticles to Cr(VI) ions, mediated by phytochemical functional groups. The toxic hexavalent chromium is reduced to trivalent chromium, which is significantly less toxic and more stable. 85% Reduction Efficiency Achieved within 2 hours 20-50 Particle Size (nm) Optimal for catalysis 2-4 Optimal pH Range Acidic conditions

9. Key Findings & Discussion Exceptional Reduction Efficiency Over 85% reduction of Cr(VI) to Cr(III) achieved within 2 hours under optimized conditions, demonstrating strong catalytic activity Spectroscopic Confirmation FTIR analysis showed disappearance of characteristic Cr(VI) peaks, providing molecular evidence of successful reduction reaction Morphological Changes Post-reaction SEM imaging revealed slight nanoparticle agglomeration, indicating surface interaction with chromium species Synergistic Action Results demonstrate powerful combination of plant biomolecules and metal oxide nanoparticles for environmental remediation

10. Advantages of Green Nanotechnology Approach Environmentally Benign No toxic chemical reducing agents required—plant extracts provide natural, safe synthesis pathway Cost-Effective & Scalable Abundant plant material and simple synthesis procedure enable large-scale production at minimal cost Waste-to-Value Conversion Transforms hazardous Cr(VI) contamination into non-toxic Cr(III), supporting UN SDG 6 (Clean Water & Sanitation) Bioeconomy Contribution Exemplifies plant-based green biotechnology for sustainable industrial applications and circular economy principles

11. Conclusions & Future Perspectives Key Conclusions Catharanthus roseus -mediated CuO nanoparticles demonstrate high efficiency in reducing hexavalent chromium Green synthesis approach is sustainable, economical, and scalable for industrial applications Technology shows promise for wastewater treatment and heavy metal remediation Represents significant contribution to environmental nanobiotechnology and sustainable bioeconom y Future Research Directions Field trials in industrial wastewater, regeneration studies, and exploration of other plant species for enhanced performance. Acknowledgments MJP Rohilkhand University, Bareilly Indian Botanical Society & NEHU, ShillongMentorship by Dr. Pankaj Kumar Arora 48th All India Botanical Conference NEHU Shillong, 2025"Exploring Green Biotechnology in the Scotland of the East"

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