Nanoparticle Tracking Analysis (NTA) utilizes the properties of both light scattering and Brownian motion in order to obtain the particle size distribution of samples in liquid suspension.
A laser beam is passed through the sample chamber and the particles in suspension in the path of the beam scatter light in such a manner that they can be easily visualized via a long working distance, x20 magnification microscope onto which is mounted a video camera. The camera captures a video file of the particles moving under Brownian motion. The Nanoparticle Tracking Analysis (NTA) software tracks many particles individually and using the Stokes Einstein equation calculates their hydrodynamic diameters. The NanoSight range of instruments provides high resolution particle size, concentration and aggregation measurements while a fluorescence mode provides specific results for labelled particles. The range provides real time monitoring of the subtle changes in the characteristics of particle populations with all of these analyses confirmed by visual validation.
The technique enables the simultaneous measurement of multiple characteristics saving on time and sample volumes while minimal sample preparation and instrument consumables reduces running costs on a day to day basis.
ASTM E2834-12(2012) Standard Guide for Measurement of Particle Size Distribution of Nanomaterials in Suspension by Nanoparticle Tracking Analysis (NTA). Applications include: