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Efficient, easy-to-use kits for labeling antibodies and other proteins with our superior CF® dyes and other labels.
Jump to a section below to choose a kit that’s right for you:

Easy-to-use with minimal hands-on time, Mix-n-Stain™ kits require no purification after labeling
Mix-n-Stain™ kits specific for labeling nanobodies (single variable or VHH domains)
Antibody labeling for flow cytometry made easy
Make your own enzyme-coupled antibodies
Create fluorescent SNAP-tag®, CLIP-tag™, Halotag® & other ligands, no purification required
Larger scale kits, for optimized protein labeling & purification
Kits for labeling antibodies with our superior near-IR CF® Dyes, for in vivo small animal imaging


Mix-n-Stain™ antibody labeling kits dramatically simplify the process of antibody labeling. The resulting conjugates perform comparably to pre-labeled antibodies from leading suppliers. Because the labeling is covalent, the conjugates are stable for long-term storage, and ideal for multi-color imaging and multiplex flow cytometry.

Each Mix-n-Stain™ kit comes with everything you need to perform the conjugation. Without a separation step, you will have an optimally labeled antibody conjugate ready to be used in any immunofluorescence staining experiment.

One breakthrough feature of Mix-n-Stain™ kits is that antibody labeling can be conducted in the presence of many common buffer components such as BSA, gelatin, azide and low concentrations of Tris. As a result, the kits are compatible with most commercial antibody formulations without an antibody purification step prior to the conjugation process.

See below for our selection of Mix-n-Stain™ kits with a variety of label options.

Rapid Antibody Labeling with Next-Generation Fluorescent CF® Dyes, Biotin, & More

With Mix-n-Stain™ CF® Dye Antibody Labeling Kits, you can covalently label as little as ≤5 ug up to 100 ug of an antibody in just 30 minutes, with minimal hands-on time and 100% recovery of antibody. With slight modification in protocol, antibodies can be labeled in the presence of BSA, gelatin, or ascites fluid, for unrivaled convenience. See the Compatibility and Protocol Selection Flowchart below, or download the Product Protocol for a step-by-step worksheet to determine kit compatibility with your antibody.

These kits feature a choice of 29 superior CF® dyes, which have advantages in brightness and photostability compared to Alexa Fluor®, DyLight®, or other fluorescent dyes. Due to the high water solubility of CF® dyes, other proteins like BSA or gelatin in the labeling reaction have minimal effect on non-specific background, because non-IgG proteins are washed away during IF staining. We also offer Mix-n-Stain™ kits for biotin, FITC, DIG, and DNP labeling, as well as Mix-n-Stain™ Maxi Antibody Labeling Kits for 1 mg scale labeling reactions.


  • 3 kit sizes: 5-20 ug, 20-50 ug, or 50-100 ug Ab
  • Choice of 29 CF® Dye colors, biotin, FITC, or haptens
  • Less than 30 seconds of hands-on time
  • 30 minutes total reaction time
  • No purification of the product is required
  • Compatible with common antibody stabilizers

Compatible with antibody stabilizers and ascites

Monoclonal mouse anti-tubulin clone DM1A in ascites or purified in PBS with 1% BSA was labeled with CF®488A Mix-n-Stain™ using the modified protocol for total protein labeling. The Mix-n-Stain™-labeled antibodies performed comparably in immunofluorescence staining of HeLa cells as unlabeled antibody (in ascites) detected with secondary antibody.

Combine direct & indirect IF for flexible multiplexing

Combined direct and indirect immunofluorescence staining of rat testis with mouse anti-tubulin and CF®488A goat anti-mouse (min x rat) (microtubules, green), CF®555 Mix-n-Stain™ labeled mouse anti-ZO1 (tight junctions, red) and CF®640R phalloidin (actin filaments, cyan). See our Tech Tip: Combined Direct & Indirect Immunofluorescence Using Primary Antibodies from the Same Host.

Featuring CF® Dyes with superior brightness

Mouse anti-transferrin receptor antibody from (endosome and plasma membrane marker) was labeled using Lightning-Link® Rapid DyLight® Conjugation Kits from Novus Biologicals (left) or Mix-n-Stain™ CF® Dye Antibody Labeling Kits (right) according to manufacturers’ instructions. The CF® dye conjugates show higher signal and more specific staining compared the DyLight®conjugates when imaged using the same settings, due to the superior brightness of CF® dyes. The insets show the same field of view imaged with a higher gain setting.

Mix-n-Stain CF® Dye, Biotin, FITC & Hapten Antibody Labeling Kits

Product descriptionLabel optionsLabeling time
Mix-n-Stain™ CF® Dye Antibody Labeling KitsChoice of 29 bright & photostable CF® Dyes30 minutes (~30 seconds hands-on time)

Download the product protocol
Mix-n-Stain™ Maxi Antibody Labeling KitsChoice of 12 bright & photostable CF® Dyes, FITC, Cyanine 555 (Cy®3), and Cyanine 647 (Cy®5)
Mix-n-Stain™ Nanobody Labeling KitsChoice of 7 bright & photostable CF® Dyes and Biotin
Mix-n-Stain™ FITC Antibody Labeling KitsFITC
Mix-n-Stain™ Biotin Antibody Labeling KitsBiotin
Mix-n-Stain™ Digoxigenin Antibody Labeling KitsDigoxigenin (DIG)
Mix-n-Stain™ DNP Antibody Labeling KitsDNP

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Mix-n-Stain™ Nanobody Labeling Kits are designed specifically for labeling single-domain Nanobodies® (also called camelid single variable or VHH domains) with one of Biotium’s bright and photostable CF® dyes or biotin. The kits allow optimal labeling of between 5-50 ug of nanobody in just 30 minutes, with minimal hands-on time and no purification. Labeling tolerates common buffer additives, including BSA.

The kits come with a selection of our next-generation CF® dyes or biotin. CF® dyes have advantages in brightness and photostability compared to Alexa Fluor®, DyLight®, and other fluorescent dyes (learn more about CF® Dyes).


  • Label 5-20 ug or 20-50 ug of Nanobody®
  • Choice of 7 CF® Dye colors or biotin
  • Simple 30 minute labeling, no purification
  • Compatible with common stabilizers
  • Dye options for super-resolution and 2-photon imaging (learn more)
Anti-histone nanobody was labeled using the Mix-n-Stain™ CF®488A 5-20 ug Nanobody Labeling Kit, then used to stain methanol-fixed HeLa cells at 2 ug/mL. Labeling either 5 ug or 20 ug of nanobody generated bright and specific conjugates, but protein amounts at the upper end of the kit range were more optimal. Adding 15 ug BSA to 5 ug nanobody to bring the protein amount to 20 ug produced more optimal labeling and brighter staining. Labeled BSA did not affect specificity of staining.

Overview of the Mix-n-Stain™ Nanobody Labeling Protocol.


Mix-n-Stain™ Nanobody Labeling Kits

LabelEx/EmLabeling size
(ug nanobody)
Catalog number
BiotinN/A5-20 ug92500
20-50 ug92501
CF®405S404/431 nm5-20 ug92502
20-50 ug92503
CF®488A490/515 nm5-20 ug92504
20-50 ug92505
CF®568562/583 nm5-20 ug92506
20-50 ug92507
CF®594593/614 nm5-20 ug92508
20-50 ug92509
CF®640R642/662 nm5-20 ug92510
20-50 ug92511
CF®647650/665 nm5-20 ug92512
20-50 ug92513
CF®680R680/701 nm5-20 ug92514
20-50 ug92515
Note: Before selecting a kit, please download the Product Protocol to see Kit Compatibility and Protocol Selection guidelines.

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R-PE (commonly called PE), APC and PerCP are fluorescent proteins widely used in flow cytometry. These fluorophores belong to the family of phycobiliproteins, which are derived from cyanobacteria and eukaryotic algae. Because of their high extinction coefficients and quantum yields, they are the brightest flow cytometry dyes in their respective channels. They also can be coupled to small molecule dyes to form long Stokes shift tandem dyes, which expand multiplexing capability. Traditional protein-protein conjugation is complicated and time-consuming, but Mix-n-Stain™ kits greatly simplify the procedure, making it easy for any biologist to label their antibody for flow cytometry.


  • Label 25-50 ug, 50-100 ug, or 1 mg Ab
  • Labeling procedure of ~ 4 hours or less with no purification
  • Choice of 5 bright fluorescent labels
  • Novel RPE-CF®647T & APC-CF®750T tandem dyes for PE-Cy®5/APC-Cy®7 channels
  • Greatly simplifies antibody labeling for flow cytometry


Anti-mouse secondary antibody was labeled with APC using either the Mix-n-Stain™ APC Labeling Kit, or a competitor’s APC labeling kit. The antibodies were used to detect mouse anti-CD3 staining of Jurkat cells. The Mix-n-Stain™ labeled antibody showed lower background without primary antibody (pink) and higher signal on CD3-labeled cells (blue).

Mix-n-Stain™ Fluorescent Protein Antibody Labeling Kits

Mix-n-Stain™ R-PE
Antibody Labeling Kit
496, 546, 565/
578 nm
9229825-50 ug IgG
PI-Mix-n-Stain™ R-PE
~4 hours
(~15 min. hands-on)
9229950-100 ug IgG
Mix-n-Stain™ APC
Antibody Labeling Kit
650/660 nm9230625-50 ug IgG
PI-Mix-n-Stain™ APC
9230750-100 ug IgG
Mix-n-Stain™ PerCP
Antibody Labeling Kit
482/677 nm9230825-50 ug IgG
PI-Mix-n-Stain™ PerCP
9230950-100 ug IgG
Mix-n-Stain™ RPE-CF®583R
Antibody Labeling Kit
(PE-Cy®5 channel)
9244225-50 ug IgG
PI-Mix-n-Stain™ RPE-CF® Dye
~2 hours
(few min. hands-on)
9244350-100 ug IgG
Mix-n-Stain™ RPE-CF®647T
Antibody Labeling Kit
(PE-Cy®5 channel)
9234025-50 ug IgG
PI-Mix-n-Stain™ RPE-CF® Dye
9234150-100 ug IgG
923461 mg IgG
Mix-n-Stain™ APC-CF®750T
Antibody Labeling Kit
650/780 nm
(APC-Cy®7 channel)
9231025-50 ug IgG
PI-Mix-n-Stain™ APC-CF®750T
9231150-100 ug IgG
Note: Kits are not recommended for labeling IgM antibodies. Cy Dye is a registered trademark of GE Healthcare.

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Mix-n-Stain™ Enzyme Antibody Labeling Kits allow you to prepare antibody conjugates labeled with horseradish peroxidase (HRP), alkaline phosphatase (AP), or glucose oxidase (GOx) in about 2-3 hours. The resulting labeled antibodies are suitable for use in applications such as western blotting, ELISA and immunohistochemistry.


  • Label with HRP, alkaline phosphatase (AP), or glucose oxidase (GOx)
  • 2-3 hour labeling, with no purification
  • Compatible with western blotting, ELISA and immunohistochemistry

Mix-n-Stain™ Enzyme Antibody Labeling Kits

Product descriptionCatalog numberReaction size Product protocolLabeling time
Mix-n-Stain™ HRP Antibody Labeling Kit9230010-20 ug antibody
PI-Mix-n-Stain™ HRP
~3.5 hours (few minutes hands-on time)
9230125-50 ug antibody
9230250-100 ug antibody
Mix-n-Stain™ Maxi HRP Antibody Labeling Kit924371 mg antibody
PI-Mix-n-Stain™ Maxi HRP
Mix-n-Stain™ Alkaline Phosphatase Antibody Labeling Kit9231425-50 ug antibody
PI-Mix-n-Stain™ AP
~2 hours (few minutes hands-on time)
9231550-100 ug antibody
Mix-n-Stain™ Glucose Oxidase Antibody Labeling Kit9231225-50 ug antibody
PI-Mix-n-Stain™ GOx
9231350-100 ug antibody

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Mix-n-Stain™ CF® dye small ligand labeling kits are designed for rapid labeling of small (MW ~ 150 – 5,000) and relatively high affinity biological ligands (or substrates). Labeling takes about 30 minutes, without a final purification step. The ligands to be labeled must contain an aliphatic amine group that is not required for biological activity of the ligand. The amine group will form a covalent linkage with the reactive CF® dye provided in the kit. For example, suitable ligands or substrates include SNAP-tag®, CLIP-tag™ and HaloTag® ligands with an aliphatic amine. Many other small ligands are also possible candidates if they meet the criteria described above.

Simply mix your small molecule ligand with the reaction buffer and the optimally formulated dye provided, and incubate for 30 minutes, followed by a brief 5 minute quenching step. No reactive Mix-n-Stain™ dye is available at the end of labeling; therefore the conjugate is ready for cell staining and imaging without further purification. Mix-n-Stain™ labeled ligands perform comparably to commercially-available pre-labeled ligands (Figure 1), at a fraction of the cost.

For live cell imaging, the Mix-n-Stain™ small ligand kits are ideal to generate fluorescent chemical tags that provide smaller, brighter, and more versatile alternatives to fluorescent proteins. Labeling of various chemical tags with Mix-n-Stain™ kits yielded highly efficient and specific labeling of the target proteins both on surface and inside of living cells. The Mix-n-Stain™ small ligand kits have also been proven compatible with fixed cell imaging and gel-based assays.


  • Choice of 10 CF® Dye colors for extracellular staining
  • Choice of 5 CF® Dye colors for intracellular staining
  • For labeling molecules with a MW of 150-5000, containing an inactive aliphatic amine
  • Suitable ligands or substrates include SNAP-tag®, CLIP-tag™ and HaloTag® ligands
  • 30 minutes total reaction time, no purification necessary
Figure 1. Live cell imaging of HeLa cells expressing CLIP-NK1R labeled with (A) CLIPamine conjugated to green fluorescent CF®488A using Mix-n-Stain™ compared to (B) CLIP-surface 488 from New England BioLabs. Cell nuclei were stained blue with Hoechst 33342.
Figure 2. Three color imaging in live HeLa cells. Cell surface protein ADRβ2 was labeled using the CF®488A Mix-n-Stain™ kit via the SNAP-tag® (green). Mitochondrial protein Cox8A was labeled using the CF®540 Mix-n-Stain™ kit via the CLIP-tag™ (red). Cell nuclei were stained blue with Hoechst 33342.

Mix-n-Stain™ Small Ligand Kits

Product descriptionLabel optionsLabeling time
Mix-n-Stain™ CF® Dye Small Molecule Labeling KitsExtracellular Staining: Choice of 10 bright and stable CF® Dyes~30 minutes (minimal hands-on time)

Download the product protocol
Intracellular Staining: Choice of 5 bright and stable CF® Dyes

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CF® Dye SE Protein Labeling Kits allow you to label your antibody of interest with one of our many bright and photostable CF® Dyes. The difference is that while the Mix-n-Stain™ kits come optimized for consistent labeling of small amounts of antibody, the SE Protein Labeling Kits are designed for 3 labelings of up to 1 mg protein with removal of free dye after labeling. The SE Protein Labeling Kits allow the user to optimize the amount of dye and antibody and determine the degree of protein labeling, for optimization of labeling and antibody performance.


  • Choice of 19 CF® Dye colors or biotin
  • Reagents for 3 labeling reactions with purification
  • Each reaction can label up to 1 mg of antibody or protein
  • Includes instructions for determining degree of labeling


VivoBrite™ Antibody Labeling Kits use the same labeling technology as our SE Protein Labeling Kits. The kits include the same components as the SE Protein Labeling Kits, with the addition of a syringe and syringe filter to sterile filter the labeled protein, allowing it to be used for in vivo small animal studies. The VivoBrite™ kits are offered in 4 near-IR CF® Dye colors, which are useful for small animal in vivo imaging. Biotium’s near-IR fluroescent dyes are best in class for brightness, photostability, and water solubility.


  • Choice of 4 near-IR CF® Dye colors
  • Kit contains reagents for 3 labeling reactions
  • Each reaction can label up to 1 mg of antibody
  • Kit can also be used to label other proteins
  • The resulting labeled protein is purified and sterile

Protein Labeling Kits

Product descriptionLabel optionsProduct protocol
CF® Dye SE Protein Labeling Kits19 CF® Dye colors across the spectrum, plus biotinPI-CF® Dye SE Protein Labeling Kits
VivoBrite™ Antibody Labeling Kits for Small Animal In Vivo Imaging4 near-IR CF® DyesPI-VivoBrite™ Antibody Labeling Kits


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Alexa Fluor is a registered trademark of Thermo Fisher Scientific. Cy is a registered trademark of GE Healthcare. SNAP-tag is a registered trademark of New England Biolabs. CLIP-tag is a trademark of New England Biolabs. HaloTag is a registered trademark of Promega.

Mix-n-Stain™ Biotin Antibody Labeling Kit

From: $106 Sizes: 5-20 ug labeling, 20-50 ug labeling, 50-100 ug labelingCatalog #: 92244, 92266, - 92286View allHide

Mix-n-Stain™ CF® Dye Antibody Labeling Kits

From: $106 Sizes: 5-20 ug labeling, 10-20 ug labeling, 20-50 ug labeling, 25-50 ug labeling, 50-100 ug labelingCatalog #: 92433, 92432, 92431, 92430, 92429, 92428, 92427, 92426, 92425, 92230, 92231, 92232, 92233, 92234, 92235, 92236, 92237, 92238, 92239, 92240, 92241, 92242, 92243, 92245, 92246, 92247, 92248, 92250, 92251, 92252, 92253, 92254, 92255, 92256, 92257, 92258, 92259, 92260, 92261, 92262, 92263, 92264, 92265, 92267, 92268, 92270, 92271, 92272, 92273, 92274, 92275, 92276, 92277, 92278, 92279, 92280, 92281, 92282, 92283, 92284, 92285, 92287, 92288, 92289, 92290, 92291, 92303, 92304, 92305, 92316, 92317, 92318, 92319, 92320, 92321, 92322, 92323, 92324, 92331, 92332, 92333, 92334, 92335, 92336, 92337, 92338, - 92339View allHide

Mix-n-Stain™ CF® Dye Small Ligand Labeling Kits

From: $168 Sizes: 1 labelingCatalog #: 92350, 92351, 92352, 92353, 92354, 92355, 92356, 92357, 92358, 92359, 92360, 92361, 92362, 92363, - 92364View allHide

Mix-n-Stain™ Digoxigenin Antibody Labeling Kit

From: $116 Sizes: 5-20 ug labeling, 20-50 ug labeling, 50-100 ug labelingCatalog #: 92328, 92329, - 92330View allHide

Mix-n-Stain™ Enzyme Antibody Labeling Kits

From: $101 Sizes: 25-50 ug labeling, 50-100 ug labelingCatalog #: 92300, 92301, 92302, 92312, 92313, 92314, - 92315View allHide

Mix-n-Stain™ FITC Antibody Labeling Kit

From: $67 Sizes: 5-20 ug labeling, 20-50 ug labeling, 50-100 ug labelingCatalog #: 92294, 92295, - 92296View allHide

Mix-n-Stain™ Fluorescent Protein & Tandem Dye Antibody Labeling Kits

From: $122 Sizes: 25-50 ug labeling, 50-100 ug labeling, 1 mg labelingCatalog #: 92298, 92299, 92306, 92307, 92308, 92309, 92310, 92311, 92340, 92341, 92346, 92442, - 92443View allHide

CF® Dye & Biotin SE Protein Labeling Kits

From: $406 Sizes: 3 labelingsCatalog #: 92208, 92209, 92210, 92211, 92212, 92213, 92214, 92215, 92216, 92217, 92218, 92219, 92220, 92221, 92222, 92223, 92224, 92225, 92226, - 92228View allHide

VivoBrite™ Rapid Antibody Labeling Kits for Small Animal In Vivo Imaging

From: $440 Sizes: 3 labelingsCatalog #: 92160, 92161, 92162, - 92163View allHide

Mix-n-Stain™ Maxi Antibody Labeling Kits, 1 mg Labeling

From: $490 Sizes: 1 mg labelingCatalog #: 92415, 92419, 92420, 92404, 92421, 92405, 92406, 92407, 92408, 92409, 92410, 92422, 92423, 92424, - 92411View allHide

Mix-n-Stain™ Nanobody Labeling Kits

From: $120 Sizes: 5-20 ug labeling, 20-50 ug labelingCatalog #: 92501, 92500, 92502, 92503, 92504, 92505, 92506, 92507, 92508, 92509, 92510, 92511, 92512, 92513, 92514, - 92515View allHide


Mix-n-Stain™ Antibody Labeling Kits

For CF® dye, cyanine dye, FITC, biotin, DNP, and dig kits, see the Mix-n-Stain™ Kit Compatibility and Protocol Selection Flowchart, below. We also recommend downloading the updated Product Protocol and completing the pre-labeling checklist to find the right protocol and kit size to use for each antibody you wish to label. Learn more about CF® dyes on our CF® Dye Technology Page, or download the CF® Dye Brochure. Note that Mix-n-Stain™ Maxi 1 mg Scale Kits, Mix-n-Stain™ Fluorescent Protein Labeling Kits (R-PE, APC, PerCP, or tandem dye), Mix-n-Stain™ Enzyme Labeling Kits (AP, HRP, GOx) have different compatibility requirements and labeling protocols. Check the protocol for your kit to verify that your antibody is compatible with labeling, then choose a kit size that matches your the amount of antibody you wish to label.  
Mix-n-Stain™ CF® Dye Antibody Labeling Kit Compatibility and Protocol Selection Flowchart. Click to enlarge.

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There is no need to measure the dye amount or vary the reaction time as long as the amount of your antibody to be labeled falls within the range specified for each kit. With Mix-n-Stain™ labeling kits optimal labeling is ensured because of the proprietary dyes and reaction buffer.

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The kits are optimized for labeling antibodies with a concentration between 0.5-1.0 mg/mL. If your antibody solution is too dilute, you can concentrate it by centrifugation using the ultra-filtration vial provided in the kit. If your antibody solution is too concentrated, you can dilute it with 1x PBS. Antibody concentrations outside the recommended range may result in either under or over labeling.

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CF® Dyes

The exact chemical structures of CF® dyes are currently confidential but will be fully disclosed at a later stage when pending patents become granted. In general terms, the structure of a CF® dye may be divided into two parts: a) dye core structure (i.e. the aromatic ring skeleton that defines the dye’s color or absorption/emission wavelengths), and b) core structure-modifying elements. At present, CF® dyes bear the core structures of coumarin, pyrene, rhodamine or cyanine dyes. Blue fluorescent CF® dyes are based on coumarin or pyrene dye core structure, while green to near-IR CF® dyes are based on either cyanine or rhodamine dye core structures. Core structure-modifying elements refer to various chemical attachments to the core structure and are a key aspect of the CF® dye invention that makes CF® dyes superior to other commercial dyes.

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Rhodamine-based CF® dyes (designated R) generally have better photostability but weaker fluorescence than their cyanine-based equivalents (designated C). Therefore, rhodamine-based near-IR CF® dyes are a better choice for microscopy, while cyanine-based CF® dyes are more ideal for flow cytometry, Western blotting, and other applications where photobleaching is less of a concern. Another factor to consider is the size of the dyes. Some of the cyanine-based near-IR CF® dyes are much larger than the rhodamine-based equivalents. For antibody labeling, either version of the CF® dyes is suitable. However, for applications where the dye size may cause a steric problem, the smaller dye may be a better choice.

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All three of these dyes can be excited by the 405 nm laser (or UV mercury lamp). They differ in their emission wavelengths. CF®405S has blue fluorescence emission at 431 nm, similar to AlexaFluor® 405, Cascade Blue®, and DyLight™ 405 (Thermo Scientific). CF®405M has longer wavelength blue fluorescence emission at 452 nm, similar to Horizon™ V450 (BD Biosciences) and Pacific Blue® (Thermo Scientific). CF®405L has orange fluorescence emission at 545 nm, similar to Pacific Orange® (Thermo Scientific). We recommend choosing the dye that best fits your instrument’s detection settings. See our CF® Dye Quick Reference Table and CF® Dye Selection Guide for more information on CF® dyes.

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