Elucidating Diversity of Exosomes: Biophysical and Molecular Characterization Methods

Abstract

Exosomes are cell-secreted nanovesicles present in biological fluids in normal and diseased conditions. Owing to their seminal role in cell-cell communication, emerging evidences suggest that exosomes are fundamental regulators of various diseases. Due to their potential usefulness in disease diagnosis, robust isolation and characterization of exosomes is critical in developing exosome-based assays. In the last few years, different exosome characterization methods, both biophysical and molecular, have been developed to characterize these tiny vesicles. Here, in this review we summarize: first, biophysical techniques based on spectroscopy (e.g., Raman spectroscopy, dynamic light scattering) and other principles, for example, scanning electron microscopy, atomic force microscopy; second, antibody-based molecular techniques including flow cytometry, transmission electron microscopy and third, nanotechnology-dependent exosome characterization methodologies.

Message in a Bottle: Upgrading Cardiac Repair into Rejuvenation

“…To date, there is no consensus on standardised methods to separate the different vesicle sub-fractions in a reproducible way. As a result, isolation, characterisation and functional analysis of EVs have become a major focus in this research field [107,108].…”

Surface-Enhanced Raman Spectroscopy (SERS) Based on ZnO Nanorods for Biological Applications

“…These biomarkers are now understood to be fundamental to healthy intercellular communication and can be produced in diseased cells. Label free Raman spectroscopy is useful for verification of biological samples ranging from nanoscale to millimeter size, such as tissue [1,2], cells [3][4][5], bacteria [6,7], exosomes [8,9], and proteins [10,11]. After incident laser emission with a single wavelength, Raman spectroscopy can identify biomarkers with the spectral peak position as a fingerprint because the molecular vibrations of the sample are represented by spectra due to inelastic scattering.…”

Extracellular Vesicles: Isolation Methods

“…A large number of excellent reviews have been published recently reporting the different EV isolation and characterization techniques. [15][16][17][18][19][20][21][22][23] However, our goal in this review is Extracellular vesicles (EVs) have recently been at the center of attention of cellular biologists and physicians as their role in intercellular communications has become progressively revealed. EVs display a huge diversity concerning their biogenesis and functions, leading to a still evolving classification comprising exosomes, microvesicles and apoptotic bodies.…”