Abstract
Exosomes are the nanoscopic lipid bi-layered extracellular vesicles that can deliver molecular medicine in the form of targeted therapeutics with great fidelity demonstrating enhanced permeability and high retention effect. In our investigation, we focused on the comparison of three major exosome isolation techniques based on the biophysical and physicochemical characteristics of exosomes isolated from COLO 205 and MCF-7 cancer cell’s conditioned media. Commercially available Total Exosome Isolation reagent (TEI), Protein organic solvent precipitation (PROSPR) and differential ultracentrifugation are the three methods used for isolation with an aim to select a suitable method for clinical translation. HRTEM images of exosomes are subjected to 3D image analysis and particle size distribution of exosomes depicted the morphological differences. Molecular and analytical characterization of exosomes using western blotting, Raman and ATR-FTIR spectroscopy and the multivariate analysis on the spectral data obtained, assessed for better molecular specifications and purity of particle. TEI method isolated exosomes with higher exosomal yield, purity, and recovery directly translatable into drug delivery and targeted therapeutics whereas ultracentrifuge had good recovery of particle morphology but showed particle aggregation and yielded exosomes with smaller mean size. PROSPR technique isolated a mixture of EVs and showed the least recovery of exosomes in particle size distribution. This comparative study should help in choosing a specific exosome isolation technique required for the objective of downstream applications.
Competing Interest Statement
The authors have declared no competing interest.