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Free Webinar on Extracellular Vesicle (EV) Isolation and Characterization on Thursday, October 1; Sponsored by Beckman Coulter, Presentation Will Begin at 9.30 AM Pacific Time, 12.30 PM Eastern Time

Beckman Coulter is sponsoring a free educational webinar titled “Extracellular Vesicle Isolation by Flow Cytometric Sorting and Characterization by Analytical Ultra-Centrifugation and Dynamic Light Scatter,” which will discuss sorting stained EV populations on a high-speed sorter to provide for their visualization, separation, and characterization. The speaker is Carley Ross (photo), Ph.D., a Staff Development Scientist from Beckman Coulter Life Sciences Research and Development, who has been aiding in the development of the MoFlo Astrios and Astrios EQ as well as carrying out her current work on the analytical ultracentrifuge (AUC). The complimentary webinar, hosted by LabRoots, Inc., will be presented on October 1, 2015, beginning at 9:30 am Pacific Time, 12.30 pm Eastern Time. For full details and free registration go to Dr. Ross has been awarded two patents, one in flow cytometric sorting and the other for extracellular vesicle work on the AUC. In addition, she has been awarded the corporate Excellence in Values prize for her work ethic and two Excellence in Innovation awards for her collaborative work on projects for the Astrios. Dr. Ross received her Ph.D from Colorado State University from the Cell and Molecular Biology program with a focus on mammalian mutation assays on a flow cytometer. She then did post-doctoral work in biochemistry by studying the development of yeast prions, with a focus on molecular and protein science. Dr. Ross’ focus now is to bring Beckman Coulter’s technology to the cutting edge with small-particle-detection of extracellular vesicles on both the flow cytometry and AUC platforms.An abstract of Dr. Ross’s presentation is provided below.

Background: The extracellular vesicle (EV) research field has dramatically expanded in the last five years. Using a high-speed flow cytometric sorter, EVs can be isolated at high rates such that researchers can differentially separate, isolate and characterize the EVs for downstream analysis. EVs contaminated with proteins, dye, or antibody aggregates of the same size, but different mass, can be characterized based on these physical properties in the analytical ultra-centrifuge (AUC). This presentation focuses on characterizing the EVs on an XLA/I AUC and dynamic light scatter isolated by flow cytometric sorting.

Methods: Extracellular vesicles were isolated from a HeLa cell line using serial ultracentrifugation. HeLa EVs were measured for total protein content and confirmed using CD63 Dyna-beads. EVs were stained with PKH26 and sorted on the MoFlo Astrios EQ using side scatter and fluorescence. Instrument performance was tested with polystyrene latex beads ranging from 22- 104 nm, and 100 nm liposomes for minimum detection limits. Absorbance and interference were used on AUC to measure the EV sedimentation. DelsaMax (DM) Core, dynamic light scatter (DLS) instruments, were used to measure the particle sizes of EV samples.

Results: The Astrios EQ was able to distinguish and sort the EVs with some overlap on SSC noise. 100 nm liposomes and 81 nm were visible above noise. EVs stained with PKH-26 and sorted on SSC and fluorescence with populations above and in the noise. Sorted fractions were analyzed on the AUC and DM for unstained, stained, and aggregate population distributions. AUC indicated EV populations with varied sizes and dye aggregates and EV size and distribution were measured by the DM with DLS.

Conclusions: Sorting stained EV populations on a high-speed sorter provides for their visualization, separation, and characterization. The AUC effectively separated particles on their sedimentation velocity and clarified issues with dye aggregation versus EV staining. Addditionally, the DelsaMax allowed for quick analysis of post-sorted populations. The Astrios EQ was able to sort EVs and AUC provided additional analysis for exosome purity.


Beckman Coulter Life Sciences’ mission is to improve the health of people around the world. A global leader in research automation, flow cytometry, centrifugation, cellular analysis, genomics products, and particle characterization, the company provides sophisticated tools for basic biological research, including: causes of disease; potential new drug development; and advancing clinical research. Beckman Coulter Life Sciences delivers the highest-quality solutions and customer support — a commitment to excellence that’s evident in everything the company does.


LabRoots is the leading scientific social networking website and producer of online educational events and webinars. The company is a powerful advocate in amplifying global networks and communities, and contributing to the advancement of science through content-sharing capabilities and encouraging group interactions. Founded in 2008, LabRoots emphasizes digital innovation in scientific collaboration, and learning. The company has become a primary source for current scientific news, webinars, virtual conferences, and more. Join LabRoots for free and become part of the largest scientific learning community in the world.

[Press release] [Free webinar registration] [LabRoots web site]