Green Synthesis of Nanoparticles PDF

# Analysing NPS by Mass Spectrometry ## Introduction * Each plant produces differently shaped and sized NPS. * Plants can produce different metabolites, some of which can act as reducing agents. * The reducing agent may be the same or different. ## Synthesis of NPS * Multiple metabolites can...

# Analysing NPS by Mass Spectrometry ## Introduction * Each plant produces differently shaped and sized NPS. * Plants can produce different metabolites, some of which can act as reducing agents. * The reducing agent may be the same or different. ## Synthesis of NPS * Multiple metabolites can be combined for the synthesis of NPS. * Sources of ions are the salt _63r Agl_ and _AgNo3_. ## Mechanism of NPS Synthesis * **Ag ion** reduction - phenolic acid, flavonoid, napthodianthrones act as reducing agents resulting in the formation of _Ag_ nuclei. * **Aggregation** of _Ag_ nuclei forms _Ag_ clusters through clapping. * **Clapping** results in the formation of _Ag_ NPS. * **Growth**: _Ag_ NPS grow. ## NPS Stabilization * **Colour Change**: Indicates the synthesis of NPS and stabilization. ## Synthesizing NPS Using A Bottom Up Approach **Metal Ions** undergo **reduction** to produce **Reduced Metal Ions**. * **Clapping**: Reduced metal ions are stabilized via clapping. * **Diverse Shapes**: Ultimately, the process produces differently shaped **NPS**. ## Application of NPS * **Textile** * **Electronics** * **Agriculture** * **Biomedicine** * **Cosmetics** * **Enviro** * **Food Safety** ## Characterizing NPS * **XRD** (X-Ray Diffraction) * **FTIR** (Fourier Transform Infrared Spectroscopy) * **UV-Vis Spec** (Ultraviolet-Visible Spectroscopy) * **TEM** (Transmission Electron Microscopy) * **SEM** (Scanning Electron Microscopy) * **Quil bat Chroms** * **Teal Sumn** ## Characterizing _Aloe vera_ NPS | Plant | Metal Ions | Size (nm) | Shape | |:---|:---|:---|:---| | Aloe vera | Au, Ag | 50-350 | Shere, Triangle | | Mangifera indica | Ag | 20 | * | | Eucalyptus macrocarpa | Au | 20-100 | Hexagonal * | | Aloe vera | In2O3 | 5-50 | Spherical | * Asterisk (*) indicates further information needed to determine the shape. ## Green Synthesis of NPS Using A "Bottom Up Approach" * **Plants** convert **metals** into **nanoparticles** * **Plant compounds** participate in the **metabolism of metal ions**. * This process contributes to the **reduction of metal ions** into **metal atoms**. * **Terpenoids**, **flavonoids**, **AA (Tryptophan & Tyrosine)** help to **reduce and stabilize** **NPS** ### Mechanism * **Plant extract** contains **meta ions**. * **Plant reducing agents**: facilitate the formation of **reduced metal atoms**. * **Nucleation**: the formation of a new phase, in this case, the formation of metal NPS. * **Organic Coating**: the formation of a layer that coats and stabilizes the particle. * **Coalescence**: the merging of particles. ## Green Synthesis: Advantages and Disadvantages **Advantages** * **Environmentally Friendly** * **Large** synthesis * **Low Temperature** * **Pressure**, **Energy**, and **Toxic Chemicals** required are low. * **Easy availability** over **micro-organisms**. **Disadvantages** * **Size and Shape Control** of NPS is difficult to control due to the heterogeneous nature of the synthesis. * **Low Yield** of **Secreted** proteins which decreases the synthesis rate. ## Biogenic Synthesis of NPS * **Cellulose** NPS (size: 40-9nm) - The shape is **spherical**. * **Zein** NPS * **Pectin** NPS **Advantages** * **Easily Available** * **Directly Used** for NP synthesis. * **Option for Waste Management** * **Does not Induce Toxin NP** * **Fast and Cost Effective Approach** * **Leads to Synthesis** using **Enzymes/Microorganisms** **Example: ** * **Ag** nanoparticles synthesized by _Pseudomonas stutzeri_ _AG 259 bacterium_. * The bacterium contains a **reductase enzyme** which participates in the reaction. * The enzyme is **NADH dependent** and the process results in the formation of **Ag** nanoparticles.