The plasma membrane (PM), consists of a lipid bilayer separating the intracellular environment from the extracellular space. Consequently, the PM plays a central role in many cell behaviors, such as cell migration, cell stretching, and signaling cascades. Additionally, PM dysfunction is an important biomarker because it is related to the cell status and is linked to many diseases.

Dojindo’s PlasMem Bright dyes overcome these limitations. PlasMem Bright dyes are designed to stain PMs for over a day. Furthermore, the PlasMem Bright dyes are more water-soluble compared with other commercially available dyes and can be diluted with culture medium. The PlasMem Bright dyes offer two different color options (green and red) and are provided as ready-to-use DMSO solutions. A working solution can be prepared easily via a single dilution step using growth medium or HBSS.

For more information on PlasMem Bright Dyes, please refer to the publication below:Takahashi, M. et al., “Amphipathic Fluorescent Dyes for Sensitive and Long-Term Monitoring of Plasma Membranes“ bioRxiv, 2020, doi: https://doi.org/10.1101/2020.11.16.379206

The general number of usable assays per 100 ul35 mm dish x 10μ-Slide 8 well x 10

Low toxicity, No washing, and High retentivity

High retentivity on plasma membrane

HeLa cells stained with each plasma membrane staining reagent were incubated for 24 hrs and each the resulting fluorescent image was compared. PlasMem Bright series had higher retentivity on plasma membrane than other products.

Clear visualization of plasma membrane

Observe morphology of neuron (differentiated SH-SY5Y cells) and localization of mitochondria in axon.

Experimental Example: Mitochondrial detection in neuroblast (SH-SY5Y cells)

The neuroblasts SH-SY5Y cells were stained with PlasMem Bright Green (green), MitoBright LT Red (red) and Hoechst 33342 (blue), and 3D images were obtained with a confocal fluorescence microscope.

<Detection Condition>Plasma Membrane (PlasMem Bright Green, green): Ex. 488 nm / Em. 500 – 560 nmMitochondria (MitoBright LT Red, red): Ex. 561 nm / Em. 560 – 620 nmNuclear (Hoechst 33342, blue): Ex. 405 nm / Em. 400 – 450 nm

<Protocol>(1) Wash SH-SY5Y cells with HBSS(2) Add PlasMem Bright Green (diluted 200 times), Hoechst 33342 (final concentration: 5 µg / ml) and MitoBright LT Red (final concentration: 0.1 µmol / l) prepared in the medium.(3) Incubate for 10 minutes(4) Wash the cells twice with HBSS(5) Observation with a fluorescence microscope

Experimental Example: Co-staining with exosomes

HeLa cells stained with PlasMem Bright Green were added with exosomes stained with the ExoSparkler Exosome Membrane labeling Kit-Red, and the uptake of exosomes into the cells was observed.

• HeLa cells (Live cell)

• HeLa cells (PFA fixed cells)

<Detection conditions>Plasma Membrane (PlasMem Bright Green, green): Ex. 488 nm / Em. 500 –560 nmExosome (ExoSparkler Exosome Membrane Labeling Kit-Red, red): Ex. 561 nm / Em. 560 –620 nm

<Protocol>(1) HeLa cells and incubate for 24 hours(2) Remove the supernatant and add PlasMem Bright Green (100-fold dilution) prepared in the medium.(3) Incubate for 10 minutes(4) Wash the cells 3 times with HBSS(5) Add 175 μl of MEM medium and 25 ul of Exosome solution stained with ExoSparkler Exosome Membrane Labeling Kit-Red.(6) Incubate overnight in a CO2 incubator(For immobilization) Wash cells twice with HBSS, add 4% PFA, incubate for 15 minutes, then wash cells twice with HBSS(7) Observed with a confocal laser scanning microscope

Experimental example: Time-lapse imaging of brain-derived mouse neuroblastoma (N1E-115 cells)

Time-lapse imaging of N1E-115 cells stained with PlasMem Bright Green diluted 200-fold in medium for 30 min.

<Detection conditions>・ Cells: N1E-115 cells (brain-derived mouse neuroblastoma)・ Medium: 5% FBS, 1% glutamine-containing D-MEM (Low-glucose)・ Culture equipment: 35 mm glass bottom dish・ Imaging equipment: Fluorescence microscope with incubator・ Shooting time: 1 hour, shooting interval: 2 minutes

Data was kindly provided from Dr. K Fukui, Shibaura Institute of Technology.

Excitation and emission spectra of PlasMem Bright dyes

Nuclear (Blue), Mitochondria (Red), Plasma Membrane (Green)