The iClick? EdU Andy Fluor? 647 Flow Cytometry Assay Kit provides a simplified, more robust assay for analyzing DNA replication in proliferating cells as compared to the traditional BrdU cell proliferation assay. In this assay, the modified thymidine analogue EdU is efficiently incorporated into newly synthesized DNA and fluorescently labeled with a bright, photostable Andy Fluor? 647 dye in a fast, highly-specific click reaction. This fluorescent labeling of proliferating cells is accurate and compatible with antibody methods due to the mild click protocol. Newly synthesized DNA is analyzed using the 633 nm laser of the flow cytometer.