Determining fluorescence Limit of Detection with Nanoparticle Tracking Analysis
NanoSight instruments can also operate in fluorescence mode where only fluorescently labeled particles are detected and measured. This application note works through an experiment to approximately establish a baseline in terms of the fluorescence limit of detection for a given fluorophore.
Introduction
The ability to detect nanoparticle fluorescence is important when attempting to distinguish a particular subset of particles from within a complex background. Particles which are fluorescent can be measured in terms of particle size and concentration to understand the nature of those particles. A typical application for this is in understanding the fate of drug delivery vectors as well as understanding the toxicology of nanoparticles in biological environments. Alternatively, fluorescently labeled antibodies may be used to bind specifically to target particles within a sample, thus providing a mechanism to identify specific particle populations within an unknown sample. This has implications in diagnostic applications such as research into exosomes and microvesicles, where specific markers can be identified and monitored in the detection of disease.
Nanoparticle Tracking Analysis (NTA), available on the NanoSight range of instruments, can operate in light scatter mode where all particles within a sample are visualized and measured (and thus does not require the sample to be fluorescently labeled to take a measurement). Alternatively, the instruments can also operate in fluorescence mode where only fluorescently labeled particles are detected and measured.