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Table 1.3 Molecular Probes kits for protein and nucleic acid labeling.

Kit Name# LabelingsKit ComponentsFeatures
Kits for Labeling Proteins with Fluorescent Dyes
APEX Antibody Labeling Kit5 labelings of 10–20 µg each of IgG antibody
  • Five vials of amine-reactive fluorescent label
  • Five APEX antibody labeling tips
  • Wash, labeling, neutralization and elution buffers
  • Dimethylsulfoxide (DMSO)
  • Labeling protocol
APEX Antibody Labeling Kits utilize a solid-phase labeling technique that captures the IgG antibody on the resin inside the APEX antibody labeling tip. Any contaminants, including stabilizing proteins, are eluted through the tip prior to labeling with the amine-reactive fluorescent dye. The fluorescent IgG conjugate is ready to use in 2.5 hours, with ~15 minutes hands-on time.
SiteClick R-PE Antibody Labeling Kit

SiteClick Qdot Antibody Labeling Kits		1 labeling of 100–125 µg of IgG antibody
  • DIBO-modified R-PE or Qdot fluorescent label
  • Labeling buffers and additive
  • β-Galactosidase
  • UDP-GalNAz
  • β-1,4-galactosyltransferase (GalT)
  • Antibody concentrators and collection tube
  • Labeling protocol
The SiteClick system is a modular, click chemistry–mediated method for enzymatically labeling essentially any antibody on its heavy chain N-linked glycans—far from the antigen-binding domain. The SiteClick antibody labeling method prevents disruption of the antigen-binding domain that can occur with traditional amine- or thiol-reactive labeling reagents and eliminates the need to genetically engineer labeling sites into the antibody prior to modification.
Alexa Fluor Antibody Labeling Kit

Pacific Blue Antibody Labeling Kit

Pacific Orange Antibody Labeling Kit		5 labelings of ~100 µg each of carrier-free antibody samples
  • Five vials of the succinimidyl ester (or tetrafluorophenyl ester) of the fluorescent dye
  • Sodium bicarbonate
  • Spin columns and collection tubes
  • Detailed protocols for conjugation, purification and determination of the degree of labeling
A buffered solution of the protein is added to one of the five vials of amine-reactive dye. The reactive dye has a succinimidyl ester (or tetrafluorophenyl ester) moiety that reacts efficiently with primary amines of proteins to form stable dye–protein conjugates. The conjugate can be purified on the included size-exclusion spin columns. Labeling and purification can be completed in less than 2 hours.
SAIVI Rapid Antibody Labeling Kit3 labelings of 0.5–3 mg each of carrier-free antibody solution
  • Three vials of amine-reactive Alexa Fluor dye
  • Sodium bicarbonate
  • Regulator solution
  • Purification resin and purification columns
  • Phosphate-buffered saline (PBS)
  • Syringes, syringe filters, column-loading pipettes and catch tubes
  • Detailed protocols for conjugation, purification and determination of the degree of labeling
SAIVI Antibody Labeling Kits provide a convenient means to label antibodies with an optimal degree of labeling for in vivo imaging applications over a 6-fold antibody concentration range with no adjustments in reaction volume, dye concentration or antibody concentration necessary. Purification of the dye-labeled antibody is achieved with a simple protocol that can be completed in less than 10 minutes. These optimally labeled antibodies are ready for applications that require azide-free reagents, such as live-cell imaging or direct injection into animals.
Alexa Fluor Microscale Protein Labeling KitThree 20–100 µg protein samples of a 12,000- to 150,000-dalton protein
  • Three vials of the succinimidyl ester (or tetrafluorophenyl ester) of the fluorescent dye
  • Sodium bicarbonate
  • Reaction tubes
  • Purification resin and spin filters
  • Detailed protocols for conjugation, purification and determination of the degree of labeling
Alexa Fluor Microscale Protein Labeling Kits provide a convenient means for labeling small amounts (20–100 µg) of purified protein with our superior Alexa Fluor dyes and purifying the resulting conjugate. Convenient spin columns are used to purify the labeled protein, with yields between 60 and 90% depending primarily on the molecular weight of the starting material. Labeling and purification can be completed in as little as 30 minutes. Microscale Protein Labeling Kits are also available for biotinylating proteins (see below).
Easy-to-Use Protein Labeling KitThree ~1 mg protein samples of a 150,000-dalton protein, such as an IgG
  • Three vials of the succinimidyl ester (or tetrafluorophenyl ester) of the fluorescent dye, each containing a magnetic stir bar
  • Sodium bicarbonate
  • Gravity-feed columns, a size-exclusion resin and concentrated elution buffer
  • Column funnels, foam column holders, disposable pipettes and collection tubes
  • Detailed protocols for conjugation, purification and determination of the degree of labeling
A buffered solution of the protein is added to one of the three vials of the amine-reactive dye. The reactive dye has a succinimidyl ester (or tetrafluorophenyl ester) moiety that reacts efficiently with primary amines of proteins to form stable dye–protein conjugates. Purification of the conjugate can be accomplished on the included gravity-feed size-exclusion columns.
FluoReporter Protein Labeling Kit5 to 10 protein samples of 0.2–2 mg each in 200 µL volumes
  • Five vials of the amine-reactive dye
  • Anhydrous DMSO
  • Reaction tubes, each containing a stir bar
  • Spin columns and collection tubes
  • Detailed protocols for conjugation, purification and determination of the degree of labeling
The amount of dye necessary for the desired protein sample is calculated using the guidelines outlined in the kit protocol. The reactive dye has a succinimidyl ester moiety that reacts efficiently with primary amines of proteins to form stable dye–protein conjugates. Purification of the conjugate can be easily accomplished using the included spin columns.
Zenon Antibody Labeling KitSee Zenon Technology: Versatile Reagents for Immunolabeling—Section 7.3
Kits for Labeling Proteins with Biotin or Dinitrophenyl (DNP)
APEX Biotin-
XX Antibody Labeling Kit		5 labelings of 10–20 µg each of IgG antibody
  • Five vials of biotin-XX sulfosuccinimidyl ester
  • Five APEX antibody labeling tips
  • Wash, labeling, neutralization and elution buffers
  • Dimethylsulfoxide (DMSO)
  • Labeling protocol
APEX Antibody Labeling Kits utilize a solid-phase labeling technique; see complete description above. The biotinylated IgG conjugate is ready to use in 2.5 hours, with ~15 minutes hands-on time.
Biotin-XX Microscale Protein Labeling KitThree 20–100 µg protein samples of a 12,000- to 150,000-dalton protein
  • Three vials of biotin-XX sulfosuccinimidyl ester
  • Sodium bicarbonate
  • Reaction tubes
  • Purification resin and spin filters
  • Detailed protocols for conjugation and purification
The Biotin-XX Microscale Protein Labeling Kit provides a convenient means for biotinylating small amounts (20–100 µg) of purified protein. Convenient spin columns are used to purify the labeled protein with yields between 60 and 90%, depending primarily on the molecular weight of the starting material. Labeling and purification can be completed in as little as 30 minutes. For determining the degree of labeling, the FluoReporter Biotin Quantitation Assay Kit for proteins is available separately or in combination with the Biotin-XX Microscale Protein Labeling Kit.
FluoReporter Mini-Biotin-XX Protein Labeling Kit5 biotinylation reactions of 0.1–3 mg each
  • Five vials of biotin-XX sulfosuccinimidyl ester
  • Reaction tubes, each containing a stir bar
  • Purification resin, spin columns and collection tubes
  • Dialysis tubing
  • Detailed protocols for conjugation and purification
The biotin-XX sulfosuccinimidyl ester (SSE) is water soluble and reacts with primary amines of proteins or other biomolecules to form stable biotin conjugates. The biotin-XX SSE has a 14-atom spacer that enhances the binding of biotin derivatives to avidin's relatively deep binding sites. Ready-to-use spin columns are included for purification of the biotinylated protein from excess reagents.
FluoReporter Biotin-XX Protein Labeling Kit5 biotinylation reactions, each with 5–20 mg of protein
  • Biotin-XX succinimidyl ester
  • DMSO
  • Gel filtration column
  • Avidin–HABA complex
  • Biotinylated goat IgG
  • Detailed protocols for conjugation, purification and determination of the degree of labeling
The biotin-XX succinimidyl ester (SE) reacts with primary amines of proteins or other biomolecules to form stable biotin conjugates. The biotin-XX SE has a 14-atom spacer that enhances the binding of biotin derivatives to avidin's relatively deep binding sites. A gel filtration column is provided for purifying the labeled proteins from excess biotin reagent. After purification, the degree of biotinylation can be estimated using the included avidin–biotin displacement assay.
FluoReporter Biotin/DNP Protein Labeling Kit5 to 10 labeling reactions of 0.2–2 mg of protein each
  • Five vials of DNP-X–biocytin-X succinimidyl ester
  • DMSO
  • Reaction tubes
  • Spin columns and collection tubes
  • Detailed protocols for conjugation, purification and determination of the degree of labeling
The FluoReporter Biotin/DNP Protein Labeling Kit is similar to other FluoReporter Protein Labeling Kits, except that it contains DNP-X–biocytin-X succinimidyl ester as the reactive label. When proteins are labeled with this chromophoric biotin derivative, the degree of biotinylation can be readily assessed from the extinction coefficient of DNP (EC360 nm = 15,000 cm-1M-1). An additional feature of the conjugates labeled with DNP-X–biocytin-X succinimidyl ester is that they can be recognized by avidin derivatives (or anti-biotin antibodies) and by anti-DNP antibodies, enabling researchers to choose among several detection techniques suitable for fluorescence and electron microscopy.
DSB-X Protein Labeling Kit5 protein conjugations of 0.5–3 mg each
  • Five vials of DSB-X biotin succinimidyl ester
  • DMSO
  • Reaction tubes
  • Purification resin, spin columns and collection tubes
  • Dialysis tubing for larger-scale separations
  • Detailed protocols for conjugation and purification
DSB-X biotin succinimidyl ester, a derivative of desthiobiotin with an additional seven-atom spacer, reacts with amine groups of biomolecules to form stable amides. The DSB-X biotin conjugate can be detected with avidin or streptavidin derivatives. Binding is almost totally reversed by addition of free biotin at neutral pH and normal ionic strength. Materials are included for both small- and large-scale preparations.
Kits for Labeling Nucleic Acids with Fluorescent Dyes
ULYSIS Nucleic Acid Labeling Kit20 labelings of 1 µg DNA
  • ULS labeling reagent and appropriate solvent
  • Labeling buffer
  • Deoxyribonuclease I (DNase I), for digesting DNA longer than 1000 base pairs prior to labeling
  • DNase I storage and reaction buffers
  • Control DNA from calf thymus
  • Nuclease-free H2O
  • Labeling protocol
The ULS reagent reacts with the N-7 position of guanine residues to provide a stable coordination complex between the nucleic acid and the fluorophore label. Separation of the labeled nucleic acids from the unreacted ULS complex can be accomplished through a simple procedure using a spin column (not provided).
ARES DNA Labeling Kit10 labelings of 1–5 µg DNA
  • 5-(3-Aminoallyl)-dUTP
  • Amine-reactive fluorescent dye and appropriate solvent
  • Sodium bicarbonate
  • Nuclease-free H2O
  • Detailed protocol for labeling DNA using reverse transcriptase or nick translation
In the first step, an amine-modified nucleotide, 5-(3-aminoallyl)-dUTP, is incorporated into DNA using conventional enzymatic labeling methods. In the second step, the amine-modified DNA is chemically labeled using an amine-reactive fluorescent dye. The amine-modified DNA can be purified using the PureLink PCR Purification Kit (K3100-01).
FISH Tag DNA KitSee Labeling Oligonucleotides and Nucleic Acids—Section 8.2
FISH Tag RNA KitSee Labeling Oligonucleotides and Nucleic Acids—Section 8.2
Oligonucleotide Amine Labeling Kit3 labelings of 50 µg each of an amine-modified oligonucleotide
  • Three vials of the amine-reactive dye
  • DMSO
  • Labeling buffer
  • Labeling protocol
The reactive dye used in the labeling has an amine-reactive succinimidyl ester moiety that reacts efficiently with an amine-modified oligonucleotide. Following the labeling reaction, the conjugate can be purified from the reaction mixture by preparative gel electrophoresis or reverse-phase HPLC.

For Research Use Only. Not for use in diagnostic procedures.