Notice: This product is being discontinued and is directly replaced by the pHrodo iFL version for improved flurescent labeling available in Green (P36015) and Red (P36014).

pHrodo™ Red Microscale Labeling Kit

Catalog number:  P35363

Related applications:

Cell Viability, Proliferation & Function

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pHrodo® Red is the new name for pHrodo®, a fluorogenic dye that dramatically increases in fluorescence as the pH of its surroundings become more acidic. Original pHrodo® and pHrodo® Red dyes are the same molecule. Use this pHrodo® Red microscale protein labeling kits to conveniently label 3 separate samples of small amounts (20-100 µg) of purified protein or antibody with pHrodo®-SE conjugate.

pHrodo® Red dye conjugates are non-fluorescent outside the cell, but fluoresce bright red in phagosomes, making them ideal tools for studies ranging from phagocytosis of bioparticles to receptor internalization. pHrodo Red™ offers staining that is faster and more accurate than ratiometric dyes.

The pHrodo® Red Microscale Labeling Kit Is:
Convenient—Labeling typically takes 2 hours with less than 30 min hands-on
Versatile—Label proteins with MW between 12 and 150 kDa
Customizable—Create your own probes for studying phagocytosis and endocytosis

Get Better Results in Endocytosis Studies
Endocytosis and phagocytosis underly physiological events ranging from host-pathogen response to receptor desensitization via internalization (as is common in the GPCR class of receptors). Once internalized, material can be acidified in endosomes or lysosomes. When conjugated to target molecules, our pHrodo® Red dye fluorogenic pH sensitive probe allows direct visual monitoring of material entering these acidic compartments. At neutral and basic pH values, pHrodo® Red dye emission is at its minimum; with acidification, pHrodo® Red dye emission is increased by as much as 8-fold (at pH 4). The fluorescence of pHrodo® Red dye is dimmed by complete media and whole blood, further improving the signal-to-noise ratio. The pHrodo® Red Microscale Labeling Kit can label proteins with molecular weights between 12 and 150 kDa, including IgG antibodies (~150 kDa) in quantities ranging from 20-100 µg.

Gain Experimental Flexibility with a Validated Technology
pHrodo® has been cited in over 150 publications and used in a variety of applications. It is validated in flow cytometry, high throughput and high content screening (HTS and HCS), and other imaging applications. pHrodo® Red offers reduced signal variability and improved timing compared to ratiometric dyes like BCECF and SNARF, and the lack of fluorescence outside the cell eliminates the need for wash steps and quencher dyes. The red fluorescence of pHrodo® Red is ideal for multiplexing applications with green-fluorescent compounds such GFP, Fluo-4, or calcein.

For Research Use Only. Not intended for any animal or human therapeutic or diagnostic use.
For Research Use Only. Not for use in diagnostic procedures.


For Use With (Equipment): Fluorescence Microscope
Labeling Scale: 20-100 µg
No. of Reactions: 3 Preps
Shipping Condition: Room Temperature
Color: Red
Emission: Visible
Excitation: Visible
Label Type: pH-Sensitive Dyes
Labeling Target: Proteins (General)
Label or Dye: pHrodo™ Red
Product Line: Molecular Probes™, pHrodo™

Contents & storage

Store at 2-8°C. Desiccate and protect from light.