During the last two decades, biomedical research at a worldwide level has been
drastically increasing its efforts to develop nanoparticle based drugs and bring them
from the bench to the bedside.
Today, many high-potent molecule-based drugs are used in suboptimal conditions: low
dosage (because of their toxicity) or lack of efficiency in the targeting specific organs,
cell types, etc.
Thanks to recent discoveries, it has been recognized that nanoparticles, like polymers
or liposomes, have excellent properties as drug delivery vehicles to address some of
these issues. When considering a nanoparticle-based drug it is critical to characterize
the size of these vectors, as it has a considerable effect on their pharmacokinetics
or their efficiency and ability to reach their target within the body. Equally, it is also
imperative to have an idea of the concentration of nano-objects and more importantly
the dosage of nano-objects loaded with the drug of interest.
Here we describe the use of Nanoparticle Tracking Analysis (NTA) for size and
concentration measurements of drug delivery nanoparticles. In addition, by using
a fluorescently tagged drug molecule, it was possible to determine how many drug
delivery nanoparticles had successfully been loaded with drug molecules.