What is the largest size of particles that can be analysed?
The upper size limit is approximately 1000 nm. The NanoSight NTA technique analyses the movement of a particle undergoing Brownian motion by tracking the spot of light it scatters. For large particles: • The diffusion of the particle reduces making the accurate determination of its mean displacement progressively less accurate. • For dense particles, sedimentation rates become significant compared to the limited Brownian motion. • The spot of light becomes so large and its edges variable between frames, thus identifying its centre becomes increasingly difficult, leading to centring errors which are as large as the particle’s movement. These effects get progressively larger as particle size increases so there is no specific limit to our upper size range. This upper limit will depend on the nature of the system. In practice, for low density and low Ri particles such as polystyrene micro-spheres their buoyancy and weaker scattering allow them to remain Brownian movers with easily identifi
