DAPI (dilactate), a blue fluorescent dye, primarily targets and binds to AT clusters within the minor groove of dsDNA, significantly enhancing fluorescence by about 20-fold upon binding. It is particularly effective in staining the nucleus, allowing for clear identification of the cell cycle phases, while it does not stain the cytoplasm. The dilactate form of DAPI exhibits greater water solubility compared to its dihydrochloride counterpart. [1] [2]

DAPI dilactate 工作液制备：1.1 储备液的制备：将 5 mg DAPI dilactate 溶解于 1 mL ddH2O 得 5 mg/mL 储备液 (DAPI, dilactate 10.9 mM)。注意：储于-20°C 或 -80°C 避光，防止反复冻融。1.2 工作液的制备：储备液在 PBS 中以 1:5000 稀释至 1 μg/mL，4°C 保存工作液。注意：可根据需要调整浓度。细胞染色：2.1 悬浮细胞 (96 孔板)：a．4°C，1000 g 离心 3-5 分钟，弃上清，PBS 洗涤 2 次 (5 分钟/次)，细胞密度为 1×10^6/mL。b．加 1 mL 工作液，室温孵育 3-10 分钟。c．4°C，400 g 离心 3-4 分钟，弃上清。d．PBS 洗涤 2 次 (5 分钟/次)。e．无血清培养基或 PBS 重悬细胞，荧光显微镜或流式细胞术检测。2.2 贴壁细胞：a．在无菌盖玻片上培养。b．从培养基上取下盖玻片，吸出多余培养基。c．加 100 μL 工作液，摇匀，室温孵育 3-10 分钟。d．培养基洗涤 2 次 (5 分钟/次)，荧光显微镜或流式细胞术检测。注意：储备液长期保存应分装储于 ≤-20°C，短期保存于 2-6°C 避光，DAPI 溶液至少可稳定保存 6 个月。