Abstract

Know What’s In Your Sample: Phenotyping of Extracellular Vesicles (EVs) with Fluorescent Nanoparticle Tracking Analysis (f-NTA)

Sven Rudolf Kreutel, Sales Director, Particle Metrix GmbH

In the last decade, Nanoparticle Tracking Analysis (NTA) has emerged as a vital and fast characterization technology for Extracellular Vesicles, Exosomes and Microvesicles. in the size range from 30 nm to 1 µm. While getting a particle size distribution, the user typically cannot discriminate whether the particle is a vesicle, protein aggregate, cellular trash or an inorganic precipitate from scatter data alone. The fluorescence detection capability of NTA enables the user to gain specific biochemical information about the particle surface and increases the resolution and the discrimination power. However, traditional NTA instruments are equipped with one laser wavelength in operation. This limits the detection of biomarkers to only a couple of fluorescence dyes. For change of excitation wavelength, it was necessary to change the laser source, a time and sample consuming step. To overcome this issue Particle Metrix developed a unique QUATT laser technology and now allows the rapid analysis of biomarker concentrations or ratios with four excitation lasers on the same sample. Here we report the multi-fluorescence detection of four independent biomarkers (CD63, CD81, CD9 and CD41) in one NTA sample with the new Particle Metrix ZetaView® QUATT for the first time.