Nanoparticle & Microparticle Synthesis

Microparticle and nanoparticle synthesis is typically achieved by physical and chemical methods. In physical methods, particles are created by reducing the size of the source material, a so-called top-down approach to microfabrication and nanofabrication. Physical techniques include milling, gas condensation, electro-spraying, lithography, and thermal decomposition.  In many chemical methods, particles are created by nucleating and growing particles from atomic or molecular precursors normally in the liquid or vapor phase of a chemical reaction, a so-called bottom-up approach. Chemical methods for synthesis of microparticles and nanoparticles include microemulsion, hydrothermal, microfluidic, chemical vapor, pyrolysis, and sol-gel processes. Chemical synthesis of nanoparticles produces nanostructures with less defects, provides access to more complex and homogeneous chemical compositions, and is easily scalable for low-cost and rapid fabrication. 

Since these techniques are often labor-intensive and result in toxic byproducts, biological methods or green nanoparticle synthesis methods have emerged, such as biogenesis with microorganisms and plant extracts. These sustainable methods produce non-toxic, eco-friendly particles suitable for biomedical and environmental applications.