LD540  别名：LD 540

LD540 是一种基于BODIPY荧光基团修饰的新型高灵敏度亲脂性染料，适用于脂滴的精确标记和成像。LD540 具有良好的光稳定性和适宜的荧光光谱，可与多种常用荧光染料 (如DAPI和Alexa Fluor 647等) 兼容，支持多色成像的需求。此外，LD540 同时适用于固定的细胞和活细胞，并能标记超小脂滴。

LD540 在水和其它极性溶剂中几乎无任何荧光，一旦与甘油三酯等中性脂肪结合，便发出明亮的红色荧光。LD540 在乙醇中最大激发光波长约为537nm，最大发射光波长约为544nm。

Staining of cells with LD540

Fixed cells
For a stock solution, LD540 was dissolved in ethanol at 0.5 mg/mL, which was stored at −20°C. Cells were fixed with 4% paraformaldehyde, permeabilized with saponin and immunostained with antibodies as described previously. Cells were incubated with a solution of 0.05–0.1 μg/mL LD540 in PBS for 5–30 min, washed three times with PBS and once with water and mounted in Mowiol/Dabco as described. For some applications, it can be useful to avoid glycerol-containing mounting media such as Moviol, because they were reported to induce LD fusion. When antibody staining was not necessary, cells were only fixed without permeabilization and stained with LD540 as described above.

Living cells
Normal growth medium was exchanged for DMEM (without phenol red), 25 mm HEPES pH 7.4 supplemented with 10% fetal calf serum (FCS) (live cell imaging medium, LCIM). Cells were stained with LD540 at 0.5 μg/mL in LCIM for 10 min followed by three washes with LCIM. The higher concentration of LD540 needed is probably due to the presence of large amounts of BSA in the FCS, which captures some of the dye.
https://pubmed.ncbi.nlm.nih.gov/19765264/