BODIPY dye is a small molecule dye with strong ultraviolet absorption ability, its fluorescence peak is relatively sharp, and the quantum yield is high. They are relatively insensitive to the polarity and pH of the environment and are relatively stable under different physiological conditions. Due to its structural asymmetry, BODIPY derives a variety of structural products. BODIPY lipid droplet dyes can well pass through the cell membrane into the cell, and localize the polar lipids in the cell to specifically stain the lipid droplets, which can be used for labeling of live cells and fixed cells . In Vitro General Protocol (Example for Py-BODIPY NHS ester) 1.Preparation of Py-BODIPY NHS ester working solution 1.1Preparation of the stock solution Dissolve 1 mg Py-BODIPY NHS ester in 382 μL DMSO to obtain 10 mM of stock solution. Note: It is recommended to store the stock solution at -20 ℃ -80 ℃ away from light and avoid repetitive freeze-thaw cycles. 1.2Preparation of BODIPY 493/503 working solution Dilute the stock solution in serum-free cell culture medium or PBS to obtain 1-10 μM of working solution. Note: Please adjust the concentration of Py-BODIPY NHS ester working solution according to the actual situation. 2.Cell staining 2.1 Suspension cells (6-well plate) a.Centrifuge at 1000 g at 4℃ for 3-5 minutes and then discard the supernatant. Wash twice with PBS, 5 minutes each time.The cell density is 1×10 6 mL. b.Add 1 mL of working solution, and then incubate at room temperature for 5-30 minutes. c.Centrifuge at 400 g at 4℃ for 3-4 minutes and then discard the supernatant. d.Wash twice with PBS, 5 minutes each time. e.Resuspend cells with serum-free cell culture medium or PBS. Observation by fluorescence microscopy or flow cytometry. 2.2 Adherent cells a. Culture adherent cells on sterile coverslips. b. Remove the coverslip from the medium and aspirate excess medium. c. Add 100 μL of working solution, gently shake it to completely cover the cells,and then incubate at room temperature for 5-30 minutes. d. Wash twice with medium, 5 minutes each time.Observation by fluorescence microscopy or flow cytometry. MCE has not independently confirmed the accuracy of these methods. They are for reference only. Form:Solid