Application of AFM, TEM, and NTA for characterization of exosomes produced by placenta-derived mesenchymal cells

Abstract

Exosomes and microvesicles usually require characterization at the single-particle level. The most commonly used methods for this purpose are transmission electron microscopy (TEM) and nanoparticle tracking analysis (NTA). However, atomic force microscopy (AFM) is also a promising method for the characterization of exosomes, and its opportunities seem underestimated. Here we describe the characterization of exosomes isolated from the conditioned media of human placenta cells using AFM, TEM, and NTA; we focus on the technical aspects of AFM imaging and data processing.