NTA Used to Characterize Microvesicles as Potential Biomarkers

NanoSight recently reported on the work of Professor Hang (Hubert) Yin’s group at the University of Colorado at Boulder in which they apply Nanoparticle Tracking Analysis (NTA) to characterize biological nanoparticles, such as microvesicles.The Yin Research Lab is interested in studying at the interface of chemistry, biology, and engineering with a particular focus on structure-based drug design, cell signaling, biochemistry, biotechnology development, and membrane protein simulations.

The main research goal of the group is to identify and design peptides that sense membrane curvature to better understand protein/peptide-lipid interactions and potentially create non-invasive probes to detect highly curved extracellular vesicles. Currently, the group is studying microvesicles as potential biomarkers of tumor progression and cancer metastasis. These nanoparticles are shed into bodily fluids targeting other cells in the body and are vital for inter-cellular communication.

Their experimental protocol involves lipid vesicle preparation by pressure-controlled extrusion through different membrane pore sizes. Different lipid vesicle sizes are prepared in order to mimic the size range of the microvesicles that are shed into the extracellular matrix. Following vesicle extrusion, it is important to validate the vesicle size. By using NTA technology, the results provide an accurate quantification of different populations of vesicle sizes present in the sample. Prior to NTA, the group mostly used dynamic light scattering (DLS) to determine the sizes of its synthetic lipid vesicles.

“NTA brought several benefits over existing methods,” said Professor Hang Yin. “The detection ranges from 10 to 2000 nm for vesicle sizes, dimensions that cover our liposome size of interest. Flow cytometry has a lower limit detection of ~200 nm to accurately measure particle sizes, so it did not reach our lower requirement, while DLS measures the average size of all the particles present in the sample rather than accurately distinguish different pools of vesicle sizes, often creating a bias toward larger particles.”

NanoSight delivers the world’s most versatile and proven multi-parameter nanoparticle analysis in a single instrument. Its NTA detects and visualizes populations of nanoparticles in liquids down to 10 nm, dependent on material, and measures the size of each particle from direct observations of diffusion. Additionally, NanoSight measures concentration, and a fluorescence mode differentiates suitably labelled particles within complex background suspensions. Zeta potential measurements assess the surface charge on particles.

NTA’s particle-by-particle methodology goes beyond traditional light scattering and other ensemble techniques in providing high-resolution particle size distributions and validates data with information-rich video files of the particles moving under Brownian motion. NanoSight’s simultaneous multiparameter characterization matches the demands of complex biological systems, hence its wide application in development of drug delivery systems, of viral vaccines, and in nanotoxicology. This real-time data gives insight into the kinetics of protein aggregation and other time-dependent phenomena in a qualitative and quantitative manner.

NanoSight has a growing role in biodiagnostics, being proven in detection and speciation of nanovesicles (exosomes) and microvesicles. It has installed more than 450 systems worldwide with users including BASF, GlaxoSmithKline, Merck, Novartis, Pfizer, Proctor and Gamble, Roche, and Unilever together with the most eminent universities and research institutes. For more information, visit www.nanosight.com.