Capturing Exosomes in Urine using a Polyamide 6 - Affinity Net

Abstract

Exosomes (EVs) are membrane-bound extracellular vesicles found in biological fluids that carry proteins/nucleic acids. In some cases, cargo is associated with diseases making EVs useful for early detection of diseases. Thus, it is key to find a technology to capture/concentrate EVs from biofluids to study their cargo. Currently, ultracentrifugation is the most common method but is time consuming and costly. In this experiment, an affinity net of Polyamide 6 (nylon) coupled with a dye (Remazol Brilliant Blue R) was developed to capture/concentrate EVs from urine. Characterization tests were performed revealing that %W(dye)/%W nylon was higher at high temperatures and acidic pH. Then, nylon - RBBR was incubated with urine samples to recover EVs. A western blot was performed using a CD63 antibody revealing that CD63 was detected during the elution step confirming the presence of EVs. The detection of CD63 indicates dyes can be used to attract EVs with specific surface proteins providing a time and cost-efficient alternative for EV capture. The use of the affinity net can be extremely beneficial to low-middle income countries for early detection of diseases without the need for high-tech or expensive machinery.