Tandem dye naming cheat sheet: APC, PE, and PerCP variants across vendors
APC-Fire 750, APC-Cy7, APC-H7, and APC-eFluor 780 are all red-laser tandems emitting near 775–785 nm, but they come from different vendors and have different stability profiles. This page maps every major PE, APC, and PerCP tandem variant to its emission peak and cross-vendor equivalents, so you can find substitutes or decode unfamiliar names quickly.
What this page covers
Why the same dye has so many names
Tandem fluorophores are proprietary; each vendor independently conjugates the same donor dye to different acceptors, or to the same acceptor using a different linker chemistry. The result is a proliferation of trade names that describe essentially the same spectral position but carry different part numbers, pricing, and stability characteristics.
For example: PE-Cy7 (BD, BioLegend, Invitrogen) and PE/Fire 810 (BioLegend) both use PE as the donor and a Cy7-like acceptor, but Fire 810 emits ~25 nm longer, which means they are not drop-in substitutes on a conventional instrument, even though the names sound like the same class of dye.
Conversely, APC-Cy7 (BioLegend) and APC-H7 (BD) are close enough to be interchangeable on most instruments, but APC-H7 uses a proprietary stabilized linker that gives more consistent lot-to-lot performance.
The emission peak is the ground truth. When in doubt, compare spectra rather than names.
Tandem variant reference
Select a donor dye to see all commercial tandem variants sorted by emission peak. Cross-vendor equivalents are grouped together so you can find a substitute at a glance.
| Name | Em. peak | Vendor(s) | Cross-vendor equivalents | Notes |
|---|---|---|---|---|
PE-eFluor 610 | 610 nm | Invitrogen (eBioscience) |
| eBioscience branding. Spectrally very close to PE-Dazzle 594. Check emission spectrum before assuming direct substitutability. |
PE-Dazzle 594 | 612 nm | BioLegend |
| BioLegend's version of PE-CF594. Very similar emission; often interchangeable on the same filter set. |
PE-CF594 | 612 nm | BD Biosciences |
| BD's Texas Red-based tandem. Excellent brightness and stability compared to older PE-Texas Red. Good first choice in the 610 nm window. |
PE-Texas Red | 615 nm | BD / Invitrogen |
| Older tandem; less stable than CF594. Most labs have migrated to PE-CF594 or PE-Dazzle 594 for better lot-to-lot consistency. |
PE/Fire 640 | 640 nm | BioLegend | — | BioLegend Fire series tandem at 640 nm. Fills the gap between PE-CF594 and PE-Cy5. Less common; verify filter availability on your instrument. |
PE-Cy5 | 667 nm | BD / BioLegend / Invitrogen |
| Older tandem with known instability. Susceptible to spectral spillover into PE channel upon degradation. PE-Vio 670 offers improved stability as a Miltenyi alternative. |
PE-Vio 670 | 670 nm | Miltenyi Biotec |
| Miltenyi's RE AffinityDye-based alternative to PE-Cy5. Generally more photostable than Cy5-based conjugates. |
PE-Cy5.5 | 695 nm | BD / BioLegend / Invitrogen |
| Prone to FRET instability like PE-Cy5. Lot-match your single-stain controls. Consider PE/Fire 700 for better stability. |
PE/Fire 700 | 700 nm | BioLegend |
| BioLegend Fire tandem with better stability than PE-Cy5.5. A practical upgrade if you are experiencing lot-to-lot variability with PE-Cy5.5. |
PE/Fire 744 | 744 nm | BioLegend | — | Fills spectral gap between PE-Cy5.5 and PE-Cy7. Useful on full-spectrum instruments. Cross-vendor equivalent is uncommon. |
PE-Cy7 | 785 nm | BD / BioLegend / Invitrogen |
| Most widely used PE tandem but highest instability risk. Light and oxygen exposure degrade signal quickly. Always run fresh single-stain controls. |
PE/Fire 810 | 810 nm | BioLegend |
| Longer-emission Fire tandem; useful on spectral instruments to push PE-based detection further into the near-IR. |
Similar-sounding dyes: know the differences
Fluorochrome names often borrow color words that overlap across brands, creating confusion about whether two dyes are interchangeable. These groups are particularly prone to mix-ups.
| Dye | Maker | Em. peak | Key note |
|---|---|---|---|
| Pacific Blue | Invitrogen | ~450 nm | UV or violet excitation; original 'Pacific' dye |
| BV421 | BD Biosciences | ~421 nm | Violet 405 nm; brighter than Pacific Blue |
| VioBlue | Miltenyi | ~450 nm | Violet 405 nm |
| V450 | BD Biosciences | ~448 nm | Older BD violet dye; largely replaced by BV421 |
| Atlantic Blue | Invitrogen | ~440 nm | UV 355 nm excitation; not violet! |
Watch out
| Dye | Maker | Em. peak | Key note |
|---|---|---|---|
| BV510 | BD Biosciences | ~510 nm | Violet 405 nm; excellent for viability or dump channels |
| VioGreen | Miltenyi | ~530 nm | Violet 405 nm; slightly longer emission than BV510 |
| V500 | BD Biosciences | ~500 nm | Violet 405 nm; older version of BV510 |
| Pacific Orange | Invitrogen | ~551 nm | Violet 405 nm; emission at ~551 nm is further out than BV510/VioGreen; confirm your detector before substituting |
| Krome Orange | Beckman Coulter | ~528 nm | Violet 405 nm; unique to Beckman Coulter instruments |
Watch out
Before you substitute one vendor for another
Cross-vendor substitution is usually possible within the same emission group, but it requires verification. Run through this checklist before swapping.
- Confirm the substitute shares the same excitation laser and filter configuration on your instrument.
- Compare emission spectra; even a 15 nm shift can require a compensation update.
- Use a spectrum viewer (BD, BioLegend, FPbase) to simulate the new dye in your full panel before ordering.
- Order a test lot before committing to a large purchase; run a side-by-side titration with the original.
- Update your compensation matrix using single-stain controls made with the new substitute, not the old one.
- If the experiment is longitudinal, document the substitution in your methods; it's a reagent change.
Same peak, different spectrum
Spectrum viewers and resources
References
- [1]Roederer M. Spectral compensation for flow cytometry: visualization artifacts, limitations, and caveats. Cytometry. 2001;45(3):194–205.
- [2]Tung JW, et al. Modern flow cytometry: a practical approach. Clin Lab Med. 2007;27(3):453–68.
- [3]Baumgarth N, Roederer M. A practical approach to multicolor flow cytometry for immunophenotyping. J Immunol Methods. 2000;243(1-2):77–97.