Development of a quantum-dot-labelled magnetic immunoassay method for circulating colorectal cancer cell detection

Figure 2 Representative fluorescence-activated cell sorting analysis of peripheral blood samples. A: Events which fell within region R1 are confirmed to be cytokeratin 19 (CK19)+ and fluorescent in FL3 (anti-CK19 conjugated with QDs); B: From the R1 gate, the events confirmed to be CK19+CD45-are those in the UL region, in UR region the events represent those that are CK19+CD45+ and fluorescent in FL1 (anti-CD45 conjugated with Alexa Fluor). We deemed that the cells in the UL are those meeting the criteria for circulating tumor cells.