Extracellular vesicles (EVs) are biological particles ranging in size from about 30 - 10,000 nanometers in diameter. Extracellular vesicles comprise diverse types of particles having a broad range of physical properties and biological origin, and include exosomes, ectosomes, microvesicles, microparticles, oncosomes, and apoptotic bodies. Extracellular vesicles have roles associated with an equally broad set of biological processes, including immune response, transfer of functional proteins and nucleic acid, elimination of unwanted materials, nutrition, surface-receptor mediated cell signaling, and numerous conditions of disease including cancer metastasis. Because of their involvement in so many physiological processes, extracellular vesicles hold enormous potential as therapeutics and biomarkers of health and disease. In these applications, accurate quantification of extracellular vesicles is critical for performing well controlled science, as well as ensuring safety and efficacy of extracellular vesicle-based products.
Research on extracellular vesicles (also known as exosomes) is maturing, and conventional vesicle quantification technologies such as nanoparticle tracking analysis (NTA), dynamic light scattering (DLS) and tunable resistive pulse sensing (TRPS) are unable to keep pace to meet the increasing standards of rigor the field demands. Emerging immobilization-based methods for exosome quantification also suffer from the complexities of the affinity-based techniques used to fix the samples before measurement.
Spectradyne's nCS1TM delivers accurate measurements of exosome/vesicle size and concentration in minutes, using microfluidic resistive pulse sensing (MRPS). The nCS1TM is fast and easy to use and requires just a few microliters of your precious sample for total analysis.
"The nCS1 is fast, accurate, and easy to use for routine EV quantification. We looked at other nanoparticle measurement solutions and the nCS1 is the only instrument that could measure the size of every nanoparticle of interest in as little as 3 uL of volume. Moreover, their customer service is superb and have went out of their way to ensure our nCS1 is always functioning well."
Joseph Sedlak, Co-Founder at Mercy BioAnalytics
For measuring the biological activity of exosomes, characterizing vesicles of different biological origin and exploring vesicle biomarker applications, accurate concentration measurements are critical for performing well-controlled experiments.
The figure below shows a comparison of Spectradyne's nCS1TM to NTA and the gold standard, Cryo-TEM. The nCS1TM measurements are in excellent agreement with those of TEM, and indicate that the exosome concentration increases to smaller particle size down to 50 nm. In contrast, NTA reports misleading results: A loss of counting efficiency is apparent for particles as large as 200 nm in diameter, leading to a 10,000-fold error by 65 nm. Critically, NTA reports a prominent peak in the exosome size distribution near 130 nm diameter that does not in fact exist. Read more about why this happens.
More and more researchers are choosing the nCS1TM for extracellular vesicle quantification because it is fast and easy to use and delivers a more accurate analysis of their vesicles than they can obtain using any other method.
The purity of extracellular vesicles isolated by size exclusion chromatography or ultracentrifugation is critical for downstream applications and analysis. Spectradyne's nCS1TM delivers highly accurate EV concentration from 50 nm up and enables researchers to increase traceability and reproducibility in their science by properly characterizing their EV purification protocol.
Figure 2 shows the distribution of EV concentration as a function of size obtained with Spectradyne's nCS1TM for 8 EV fractions separated by size exclusion chromatography. The high-resolution measurements deliver two main conclusions. First, the majority of EVs eluted in fractions 3, 4 and 5. Second, each of these fractions contained a broad distribution of sizes in the sample, indicating further purification of this sample would be required to isolate a specific size range of EVs.
The insights delivered by these nCS1TM measurements enabled significant time savings for the customer in downstream work and could not practically have been obtained with any other method.
Spectradyne's nCS1TM delivers the most accurate concentration and size measurements of extracellular vesicles available in a practical bench top solution. The nCS1TM is fast and easy to use, and requires only 3 microliters of your sample to help you do better EV science. Contact us today for a free sample measurement or to request a demonstration!