Used in molecular biology for labeling newly synthesized DNA. It is incorporated into DNA during replication by cellular polymerases, allowing detection of DNA synthesis in assays such as cell proliferation studies, apoptosis research, and cell cycle analysis. Commonly detected via click chemistry with fluorescent azide dyes, enabling visualization and quantification by fluorescence microscopy, flow cytometry, or microplate readers. Frequently applied in studies involving stem cells, cancer research, and developmental biology where tracking DNA replication is critical. Its small size and efficient incorporation make it a preferred alternative to older thymidine analogs like BrdU.