Nanoparticle tracking analysis

Nanoparticle Tracking Analysis (NTA) is a technique developed by Nanosight which allows nano-particles (smaller than the wavelength of light) to be seen via a microscope.


The particles can then be sized and analysed in real-time by individually tracking their Brownian motion for a much lower cost than using electron microscopes or other techniques.


Applications that this techniques had been proved on are viruses, gold and polystyrene standard particles, inkjet particles, metal oxides (such as TiO2, Al2O3 etc...), pharmaceutical particles for drug delivery, wear particle from orthopaedic implants, fuel additives in oil, soot in oil, CNTs, silicates and many more...


The NTA technology is most similar to Dynamic Light Scattering (DLS, also called Photon Correlation Spectroscopy, PCS) however it has a number of advantages and disadvantages when comparing the two:

Nanosight NTA advantages


• NTA conduct particle-by-particle analysis, compared to DLS’s average, so NTA avoids DLS’s bias towards larger particles and NanoSight is much better for poly-disperse systems, where NTA can better resolve several peaks in a sample population.

• NTA can detect at much lower concentrations, down to 107 particles per ml.

• NTA gives a good estimate of concentration, DLS cannot do this.

• NTA does not need calibration, and, importantly, knowledge of refractive index is not required (this is a key weakness in DLS where estimates have to be made).

• Finally, NanoSight has a unique image, rich in information, which validates the results. The image NanoSight images provide a quick and easy way to check a sample.

DLS advantages:

• DLS samples many more particles.

• DLS is ideally suited to monodisperse particle systems.

• DLS has a wider size range 3-6000nm compared to NTA's 10-1000nm.

Also, as the samples require minimal preparation the time required to process one sample is much reduced. Speculators suggest that eventually the analysis may be done in real-time with no preparation e.g. when detecting the presence of viruses or biological weapons in air.

Ankersmid M&C bvba,  (32) - 3/820 80 01