The size of particles being studied in ‘nano-technology’ is about

Nanotechnology is defined as the study, manipulation, and engineering of matter at the nanoscale, which is conventionally defined as the size range between 1 and 100 nanometers [2]. A nanometer (nm) represents one-billionth of a meter (10⁹ m) [4]. This specific range is significant because materials at this scale exhibit unique physical, chemical, and biological properties—such as increased surface area and quantum effects—that differ from their bulk counterparts [4]. The lower limit of 1 nm is typically set to distinguish nanoparticles from individual atoms or small molecules, while the upper limit of 100 nm marks the threshold where these novel 'nano' properties begin to transition into bulk material behavior [3]. International standards, including those from the EU and the U.S. National Nanotechnology Initiative, consistently utilize this 1–100 nm range for defining nanotechnology [3].

Sources

1. [1] https://www.sciencedirect.com/topics/engineering/nanoscale
2. [2] https://pmc.ncbi.nlm.nih.gov/articles/PMC6982820/
3. [4] https://education.nationalgeographic.org/resource/nanotechnology/
4. [3] https://www.sciencedirect.com/topics/engineering/nanometer-range