NTA is one of the methods the supplier reports using to characterize Bio Xsomes. Request the full analytical report, including the method and instrument used, rather than relying on a summary figure alone.
NTA is one of several analytical methods used to characterize extracellular vesicle preparations, and consensus reporting guidelines list it alongside other approaches such as imaging-based particle counting and antibody-based marker assays. No single method fully characterizes an EV preparation; NTA measures physical size and concentration but does not, on its own, confirm vesicle identity or composition.
When a supplier reports a particle concentration figure, ask which method produced it, since different analytical methods and instrument settings can report different values for the same sample. Request the underlying report rather than relying on a single number without that context. FDA states there are no FDA-approved exosome products; they are generally regulated as biologic drugs under section 351 of the PHS Act, and purchase and clinical-use decisions belong to the physician and their own regulatory counsel.
Knowing how a concentration number was generated helps a buyer interpret it correctly and compare documentation across suppliers.