Exosome Analytical Services

Exosomes / Extracellular Vesicles (EVs) are an emerging class of biologics that play a crucial role in intercellular communication and hold tremendous promise. A key challenge in the translation of exosomes is the implementation of robust analytical methods for characterization. The size, heterogeneity, and complex composition of exosomes creates challenges for the use of conventional analytical tools and strategies, especially for critical quality attributes such as purity and potency.

RoosterBio has developed an extensive panel of analytical methods to support process development and manufacturing of exosomes, which we offer to our customers as either a stand-alone service or as an integrated component of a broader process development program. Our standard exosome analytics are bundled into a Base Package and Plus Package, along with additional supplemental assays to meet a broad range of customer needs, regardless of their cell type or production process.

Contact Us For Your Analytical Needs

We Offer Two Exosome / Extracellular Vesicle Characterization Packages & Supplemental Assays Specially Designed for Starting & Advanced Programs Alike
Assay Assay Result EV / Exosome Base Package EV / Exosome Plus Package Supplemental Assay
Nanoparticle Tracking Analysis (NTA) Particle Number, Particle Size
EV / Exosome Purity % Lipidated EV by Particle Concentration
Protein Quantitation Total Protein
Surface Marker Expression Marker Expression
Cytosolic Marker Expression TSG101 Expression
miRNA Quantitation miRNA Content
miRNA Identity Analysis miRNA Identity
Albumin Analysis Process Related Impurity
CD63 Quantitation Quantified Marker Expression
Scratch Assay Wound Healing

Advanced Equipment for Advanced Analytics


ProteinSimple – Simple Western Jess

NanoFCMNanoFCM Flow NanoAnalyzer

Attune NxT Acoustic Focusing CytometerThermoFisher Attune NxT Flow Cytometer


ThermoFisher QuantStudio 5 Real-Time PCR System

Nanoparticle Tracking Analysis (NTA)

Nanoparticle Tracking Analysis is one of the most widely used methods for characterizing extracellular vesicle identity. This assay utilizes light scattering to quantify the size distribution and concentration of particles in a sample which are two key identity components of extracellular vesicle characterization. Results are provided as a concentration in particles per mL and a size distribution graph of extracellular vesicle diameters. This standardized assay is conducted using the ZetaView x30 Quatt.

Extracellular Vesicle / Exosome Purity

This extracellular vesicle assay uses the NanoFCM to measure the purity of your samples as a percent of particle population with membrane-bound lipids. As a result, these results will inform you what percentage of your particle concentration is made up of extracellular vesicles. Additional assays can utilize either the ZetaView or nanoFCM Flow NanoAnalyzer to assess tetraspanin make-up of the particle population and custom target readouts for your target of interest upon request.

Protein Quantitation

This protein quantitation assay is a widely used identity and content tool to measure total protein content of an extracellular vesicle sample. Quantitation of protein content is a useful metric for process optimization as well as the characterization of a purified sample. Results are provided as total protein per mL and a bicinchoninic acid assay (BCA), microBCA, or Bradford assay will be used depending on customer preference and sample submission.

Surface Marker Expression

CD9, CD63, and CD81 are tetraspanin proteins widely expressed in different cell types and considered identity markers of extracellular vesicles. This western blot assay provides a sensitive, semi-quantitative readout via image and densiometric conversion for all three tetraspanins in sample preparations. Additional assays utilizing the nanoFCM Flow NanoAnalyzer or Simple Western Jess to asses these tetraspanins or your surface markers of interest are available upon request.

Cytosolic Marker Expression

This identity assay measures expression of TSG101, a MISEV-recognized cytosolic marker in extracellular vesicle preparations. Results are provided via Simple Western Jess.

miRNA Quantitation

Bioanalyzer quantitation of miRNA content, as well as miRNA size distribution, provides a critical content readout for understanding your extracellular vesicles. Results are provided as miRNA concentration (miRNA per µL), gel view of miRNA migration, and electropherogram of size and signal intensity. This assay can also quantify total RNA should it be preferred.

miRNA Identity Analysis

Quantitatively identify specific miRNAs present in your extracellular vesicle samples. This real-time qPCR analysis provides readouts across several functional categories as well as a minimum of two reference readouts. Additional readouts can be customized to your target of interest upon request.

Albumin Analysis

This quantitative ELISA measures human albumin which is a common media component but impurity when found in extracellular vesicle preparations. Step-wise removal of albumin can be an informative analytical readout as well as a purity indicator for “final product” extracellular vesicle samples. The results of this purity assay are reported as albumin protein per mL.

CD63 Quantitation

Used for process development, this identity assay is a quantitative ELISA, which measures a MISEV-recognized surface marker in extracellular vesicle preparations. Results are provided as CD63 protein per mL.