EVs were isolated with anti-CD9 antibody-coated polystyrene microbeads, and tumour markers on the captured EVs were detected with antibodies decorated with quantum dot probes (i.e. QD525 nm, QD585 nm, QD625 nm) as shown in Fig. 10b supporting the detection of the EV proteins CEA, Cyfra21-1, and ProGRP. Here, CD9 is linked to neoplasm.