Live-cell fluorescence microscopy is an essential technique for the visualization of fundamentally important and physiologically relevant biological events. A key challenge with this technique is the ability to image weak fluorophors without causing cell damage, photobleaching, or undesirable changes to cell health. We have addressed this problem by developing Gibco® FluoroBrite™ DMEM, a DMEM-based formulation with background fluorescence that is comparable to PBS and 90% lower than that emitted by standard phenol red–free DMEM. Formulated to include the required nutrients for routine cell culture when supplemented with 10% fetal bovine serum and 4 mM L-glutamine or GlutaMAX™, FluoroBrite™ DMEM is designed to enhance the signal-to-noise ratio of fluorophors so that researchers can visualize even the weakest fluorescent events in an environment that promotes optimum cell health.
- Enhancement of fluorescence signal during live-cell imaging
- DMEM-based to help preserve cell health
Figure 1. FluoroBrite™ DMEM has 10% of the background fluorescence emitted by standard phenol red–free DMEM and provides a 9-fold enhancement in signal-to-noise ratio. (A) Images of live epithelial cells that have been labeled with CellLight® Golgi-GFP, BacMam 2.0 (Cat. No. C10592) and cultured in phenol red–free DMEM (Cat. No. 31053) or FluoroBrite™ DMEM with 10% fetal bovine serum. Cells in 10X images are co-labeled with CellLight® Actin-RFP, BacMam 2.0 (Cat. No. C10583). Cells in 40X images (inset) are co-labeled with ER-Tracker™ Red (BODIPY® TR Glibenclamide; Cat. No. E34250). (B) Fluorescence signal from PBS, FluoroBrite™ DMEM, and phenol red–free DMEM at 509 nm in response to excitation at 480 nm. (C) Fluorescent signal from dextran labeled with Alexa Fluor® 488 dye (Cat. No. D22910) over background in PBS, FluoroBrite™ DMEM, and phenol red–free DMEM.
Figure 2. Cell lines cultured in FluoroBrite™ DMEM and standard DMEM display comparable long-term growth over multiple passages. Graphs display the average viable cell density (solid line; left y axis) and average percent viability (dotted line; right y axis) for three cell lines cultured for several passages in a standard phenol red–free DMEM (Cat. No. 31053) or FluoroBrite™ DMEM, both supplemented with 10% fetal bovine serum and and 4 mM GlutaMAX™. Note: the Sp2 suspension cell line was tested for long-term growth in FluoroBrite™ DMEM because of its known hypersensitivity to nutrient deficiencies.