Assessment of the efficiency of encapsulation of a fluorescent drug using Nanoparticle Tracking Analysis

The use of nanoparticles in drug delivery continues to grow rapidly. Nanoparticles offer excellent pharmacokinetic properties, controlled and sustained release, and targeting of spe-cific cells, tissues or organs. When considering a nanomaterial drug delivery system, size is clearly a key parameter as it directly influences the processes of delivery, uptake, deg-radation and clearance from the body.

However, it is also imperative to have an accurate measurement of the number based concentration of nano-objects and more importantly the concentration of nano-objects loaded with the drug of interest.

This poster outlines an example where the methodology of Nanoparticle Tracking Analysis (NTA) is used to characterise nanoparticles for drug delivery purposes. Complementary to classical light scattering techniques, NTA allows nanoparticles as small as 30nm to be sized on a particle-by-particle basis, enabling high resolution profile. On the same analysis, NTA also delivers concentration measurement through a direct count (particles per ml), helping the understanding of aggregation or other particle behaviour in complex systems. Finally, a fluorescence mode allows differentiation of suitably labelled particles.