Widely used in biological research for staining DNA in cells. It binds to the minor groove of double-stranded DNA, particularly AT-rich regions, and fluoresces brightly under ultraviolet light. Commonly employed in fluorescence microscopy to visualize nuclei in both live and fixed cells. Useful in cell biology studies, including chromosome analysis, apoptosis detection, and cell cycle research. Also applied in molecular biology techniques like flow cytometry and immunofluorescence to identify and quantify DNA content. Its high affinity for DNA and strong fluorescence make it a valuable tool for studying cellular structures and genetic material.