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Nothing left to fear about labeling your antibody with PE, APC, and PerCP

Label your antibody with PE, APC, and PerCP like a pro (but without all those columns)

The phycobiliproteins R-PE (commonly referred to simply as PE), APC, and PerCP are light-harvesting protein-fluorophore complexes produced by algae. These large proteins are among the brightest known fluorophores. In addition, they have widely separated fluorescence excitation and emission. These properties have made R-PE, APC, and PerCP essential antibody labels for multicolor flow cytometry. In addition to allowing sensitive detection, they make it possible for several different fluorophores to be detected using a single excitation wavelength. Phycobiliproteins also can be linked to small molecule dyes to create tandem dyes with even longer emission wavelengths, enabling multiparameter flow analysis.

Labeling antibodies with phycobiliproteins involves protein-protein conjugation, which is much more difficult than labeling a protein with fluorescent dyes like FITC, Alexa Fluor®, or CF® dyes. Efficient conjugation with fluorescent proteins requires large quantities of pure antibody and multiple reaction and column purification steps. This is both daunting and impractical for most biologists, especially if you’re trying to conserve precious antibodies. Until recently, if your antibody of interest wasn’t commercially available with R-PE or other phycobiliproteins, then these labels simply weren’t an option for you.

Now, Biotium has optimized an alternative conjugation strategy that allows rapid, small scale antibody labeling with R-PE, APC, PerCP, and related tandem dyes. The labeling can be done in less than 4 hours with only a few minutes of hands-on time. Even better, you can label as little as 25 ug up to 100 ug antibody in common buffers. See below to compare our Mix-n-Stain™ R-PE labeling protocol to conventional labeling. With Mix-n-Stain™, what was once best left to the professionals is now fast and simple.

Mix-n-Stain™ Fluorescent Protein Antibody Labeling Kits are available for R-PE, APC, Per-CP, and tandem dyes, as well as challenging enzyme-antibody labeling reactions, including HRP, AP, and GOX. Also see our original Mix-n-Stain™ Antibody Labeling Kits, for 30 minute labeling of 5-100 ug antibody with our bright and photostable CF® dyes, biotin, and other labels.

Comparison of conventional R-PE conjugation vs. Mix-n-Stain™ R-PE Antibody Labeling Kits.

* Based on a protocol contributed to Purdue University Cytometry Laboratories by David Chambers.