Nanoparticle sizing is a field of research that focuses on measuring and characterizing the size of nanoparticles, which are particles that are typically between 1 and 100 nanometers in size. These tiny particles have unique properties due to their small size, which makes them useful in a variety of applications such as drug delivery, imaging, and electronics. Researchers in this area use a variety of techniques to measure nanoparticle size, including dynamic light scattering, electron microscopy, and atomic force microscopy. These techniques help researchers understand the physical properties of nanoparticles, such as their shape, distribution, and surface area, which can influence their behavior in different environments. Overall, nanoparticle sizing is an important area of research that helps scientists and engineers better understand and manipulate nanoparticles for various applications in industries such as healthcare, materials science, and environmental science.