Figure 4
From: Digital Detection of Exosomes by Interferometric Imaging
Exosomes purified from HEK cell line, captured with anti- CD81 antibody on silicon chip and detected by SP-IRIS (A) and AFM (B,C). (A) SP-IRIS Image of the anti-CD81 spot incubated with a suspension of exosomes (6.75E + 10 exosomes/mL), the red circles highlight the countable nanoparticles. (B) AFM image of the same spot area: the blue dots identify particles larger than 15 nm; the yellow circles show in image (B) perfectly match the particles detected by SP-IRIS in image (A). (C) Zoom in area of the anti-CD81 spot shown in the green frame highlights the particles larger than 15 nm in height detected by AFM and SP-IRIS. Particles smaller than 15–10 nm are detectable only with AFM as they are below SP-IRIS detection limit.
