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Albumin from Bovine Serum (BSA), Alexa Fluor™ 488 conjugate (Invitrogen™)

This albumin from bovine serum (BSA), Alexa Fluor 488 conjugate is a bright and photostable conjugate exceptionally suited for applications in which well-defined molecular weight tracers are needed. These applications include studying the rate of endocytosis and exocytosis and following intracellular protein processing.

Transferrin From Human Serum, Alexa Fluor™ 680 Conjugate (Invitrogen™)

Transferrin is a monomeric serum glycoprotein (~80,000 daltons) that binds to a specific receptor on the surface of vertebrate cells and delivers up to two Fe3+ atoms via receptor-mediated endocytosis—our labeled LDL complexes are useful tools for studying this phenomenon. Once iron-carrying transferrin proteins are inside endosomes, the acidic environment favors dissociation of iron from the transferrin–receptor complex. Following the release of iron, the apotransferrin is recycled to the plasma membrane, where it is released from its receptor to scavenge more iron. Fluorescent transferrin conjugates can therefore be used with fluorescent LDL to distinguish the lysosomally directed and recycling endosomal pathways.

These experiments are typically performed by adding fluorescently labeled transferrin to cultured cells and analyzing them by microscopy. We offer a biotinylated transferrin conjugate and more than 10 fluorescent versions.

Transferrin Specifications:

Label (Ex/Em): Alexa Fluor® 680 (679/702)

Amount: 15 mg solid (contains 5 mg of transferrin conjugate)

Key Applications of Labeled Transferrin
Some of the many applications for labeled transferrin include:
• Image transferrin receptor dynamics using FRET
• Observe receptor trafficking in live cells by confocal laser-scanning microscopy
• Investigate events occurring during endosomal acidification
• Measure transferrin receptor binding affinity in mammals and parasites

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

Albumin from Bovine Serum (BSA), Alexa Fluor™ 594 conjugate (Invitrogen™)

Bovine serum albumin, Alexa Fluor 594 conjugate is a bright and photostable conjugate exceptionally suited for applications in which well-defined molecular weight tracers are needed. These applications include studying the rate of endocytosis and exocytosis and following intracellular protein processing.

BODIPY™ 558/568 C12 (4,4-Difluoro-5-(2-Thienyl)-4-Bora-3a,4a-Diaza-s-Indacene-3-Dodecanoic Acid) (Invitrogen™)

The orange-red fluorescent fatty acid, BODIPY® 558/568 C12 can be used as a synthetic precursor to a wide variety of fluorescent phospholipids. Unlike fluorophores like pyrene, DPH and NBD, BODIPY® dyes are relatively environment insensitive and is fluorescent in both aqueous and lipid environments.

CaptureSelect™ Biotin Anti-Anti-α2-Macroglobulin Conjugate (Thermo Scientific™)

CaptureSelect™ Anti-α2-Macroglobulin Conjugate consists of a 13 kDa camelid antibody fragment (affinity ligand) that specifically binds with high affinity and selectivity to human α2-macroglobulin. The affinity ligand is chemically conjugated to biotin via an appropriate spacer that retains the binding reactivity of the ligand when used in combination with streptavidin-based conjugates or streptavidin pre-coated surfaces. This conjugate allows you to detect, quantitate, and characterize native and recombinant human α2-macroglobulin.

Applications for CaptureSelect Biotin Anti-α2-Macroglobulin Conjugate include ELISA, immunoprecipitation with streptavidin-coupled Dynabeads™, MSIA Streptavidin D.A.R.T.’S, Gyrolab™-based immunoassays, and label-free detection platforms such as those based on surface plasmon resonance (Biacore™ and IBIS-MX96 systems) and bio-layer interferometry (ForteBio™ Octet™ systems).

Alexa Fluor™ 594 Biocytin, Sodium Salt (Biocytin Alexa Fluor™ 594) (Invitrogen™)

The cell-impermeant, fixable, polar tracer Alexa Fluor® 594 biocytin combines the red-fluorescent Alexa Fluor® 594 fluorophore with biotin and an aldehyde-fixable primary amine. Polar tracers are commonly used to investigate cell-cell and cell-liposome fusion as well as membrane permeability and transport through gap junctions or cell uptake during pinocytosis. This water-soluble tracer can be introduced into cells by whole-cell patch clamping, iontophoresis, osmotic lysis of pinocytic vesicles or comparable methods. The biotin allows for detection and subsequent amplification with enzyme-modified streptavidins including horseradish (HRP) and alkaline phosphatase (AP) that can be used with TSA and ELF® technologies, respectively.

Vybrant™ Alexa Fluor™ 555 Lipid Raft Labeling Kit (Invitrogen™)

Vybrant Lipid Raft Labeling Kits are designed to provide convenient, reliable and extremely bright fluorescent labeling of lipid rafts in live cells. Kits include cholera toxin subunit B (CT-B) labeled with either the green-fluorescent Alexa Fluor 488, the orange-fluorescent Alexa Fluor 555 or the red-fluorescent Alexa Fluor 594 dye, as well as an antibody that specifically recognizes CT-B. A 10X solution of phosphate-buffered saline (10X PBS), pH 7.2, and detailed instructions are also included in the kits.

Lectin SBA From Glycine max (soybean), Alexa Fluor™ 594 Conjugate (Invitrogen™)

Lectin soybean agglutinin (SBA) selectively binds terminal α- and β-N-acetylgalactosamine and galactopyranosyl residues.

BODIPY™ FL C16 (4,4-Difluoro-5,7-Dimethyl-4-Bora-3a,4a-Diaza-s-Indacene-3-Hexadecanoic Acid) (Invitrogen™)

The green fluorescent fatty acid, BODIPY® FL C16 can be used as a synthetic precursor to a wide variety of fluorescent phospholipids. Unlike fluorophores like pyrene, DPH and NBD, BODIPY® dyes are relatively environment insensitive and is fluorescent in both aqueous and lipid environments.

FL - CBP-1 Peptide, 100µM

LanthaScreen® fluorescent nuclear receptor coregulator peptides contain known interaction motifs and are labeled with fluorescein. These peptides are matched and validated to complement the LanthaScreen® TR-FRET Nuclear Receptor Coregulator Assays. Assays developed using these reagents enable primary or secondary screening of nuclear receptor agonists and/or antagonists.

How they work
Ligand binding to nuclear receptors causes conformational changes in the receptor, resulting in a cascade of events, including dissociation of repressor proteins, association of coactivator proteins, and assembly of pol II and other transcriptional factors for activation of target genes. TR-FRET based assays can be developed using the LanthaScreen® panel of fluorescein-labeled coregulator peptides to investigate conformational changes of nuclear receptors upon ligand binding, either by determining the affinity of ligand-bound receptor for different coregulator peptides, or by identifying additional agonists or antagonists via displacement or recruitment of a specific coregulator peptide. In the LanthaScreen® TR-FRET RXR beta Coactivator Assay, a terbium (Tb)-labeled anti-GST antibody is used to indirectly label GSTtagged RXR beta protein. An agonist (9-cis Retinoic Acid) added to the receptor which, upon ligand binding, causes a conformational change resulting in recruitment of the Fl-D22 coactivator peptide (Figure 1). The binding of the fluorescent coregulator peptide to RXR beta causes an increase in the TR-FRET emission ratio (Figure 2).

Contents and Storage:

LanthaScreen® fluorescent nuclear receptor coregulator peptides are supplied as 100 µM solutions in peptide-appropriate buffers. Store peptides at -20°C.

CaptureSelect™ Biotin Anti-IgG-Fc (Multi-species) Conjugate (Thermo Scientific™)

CaptureSelect™ Biotin Anti-IgG-Fc (ms) Conjugate consists of a 13 kDa llama antibody fragment (affinity ligand) that specifically binds to the Fc part of IgG from multiple species. The affinity ligand is chemically conjugated to biotin via an appropriate spacer that retains the binding reactivity of the ligand when used in combination with streptavidin-based conjugates or streptavidin pre-coated surfaces.

The CaptureSelect™ Biotin Anti-IgG-Fc (ms) Conjugate allows you to:

Detect, quantitate, and characterize IgG antibodies from multiple species (all subclasses, IgG-specific), multi-species IgG-derived Fc fusion proteins, recombinant IgG antibodies, and total IgG in plasma and/or serum samples
Avoid cross-binding with other isotypes, such as IgA and IgM

Applications for CaptureSelect™ Biotin Anti-IgG-Fc (ms) Conjugate include ELISA, Western blot, Gyrolab™-based immunoassays, and label-free detection platforms such as those based on surface plasmon resonance (Biacore™ and IBIS-MX96 systems) and bio-layer interferometry (ForteBio™ Octet™ systems).

CaptureSelect™ Biotin Anti-LC-kappa (Murine) Conjugate (Thermo Scientific™)

CaptureSelect™ Biotin Anti-LC-kappa (mur) Conjugate consists of a 13 kDa llama antibody fragment (affinity ligand) that specifically binds to the constant domain of kappa light chains of mouse and rat antibodies. The affinity ligand is chemically conjugated to biotin via an appropriate spacer that retains the binding reactivity of the ligand when used in combination with streptavidin-based conjugates or streptavidin pre-coated surfaces.

The CaptureSelect™ Biotin Anti-LC-kappa (mur) Conjugate allows you to:

Detect, quantitate, and characterize all mouse and rat antibody isotypes and subclasses (for example, IgG1 to 3, IgM, and IgA), and all Fab fragments thereof, that contain a kappa light chain; as well as Fab and/or Fab2 fragments obtained after papain or pepsin digestion
Avoid cross-binding with IgG from bovine sources such as FCS
Screen antibody-antigen interactions—biotin anti-LC-kappa (mur) forms a stable [low k(diss)] complex with mouse and rat antibodies through multivalent binding

Applications for CaptureSelect™ Biotin Anti-LC-kappa (mur) Conjugate include ELISA, Western blot, Gyrolab™-based immunoassays, and label-free detection platforms such as those based on surface plasmon resonance (Biacore™ and IBIS-MX96 systems) and bio-layer interferometry (ForteBio™ Octet™ systems).

CaptureSelect™ Biotin Anti-IgG-Fc (Human) Conjugate (Thermo Scientific™)

CaptureSelect™ Biotin Anti-IgG-Fc (Hu) Conjugate consists of a 13 kDa llama antibody fragment (affinity ligand) that specifically binds to the Fc part (CH3 domain) of all four human IgG subclasses. The affinity ligand is chemically conjugated to biotin via an appropriate spacer that retains the binding reactivity of the ligand when used in combination with streptavidin-based conjugates or streptavidin pre-coated surfaces.

The CaptureSelect™ Biotin Anti-IgG-Fc (Hu) Conjugate allows you to:

Detect, quantitate, and characterize all human IgG antibodies (subclasses 1 to 4), recombinant human IgG antibodies, human IgG-derived Fc-fusion proteins including CH2 deleted (or mutated) Fc formats, and total IgG in human plasma and/or serum samples
Avoid cross-binding with other isotypes, such as IgA, IgM, IgD, and IgE, free light chains, or IgG antibodies from non-primate species (for example, bovine, horse, and murine)

Applications for CaptureSelect™ Biotin Anti-IgG-Fc (Hu) Conjugate include ELISA, Western blot, Gyrolab™-based immunoassays, and label-free detection platforms such as those based on surface plasmon resonance (Biacore™ and IBIS-MX96 systems) and bio-layer interferometry (ForteBio™ Octet™ systems).

Fibrinogen From Human Plasma, Alexa Fluor™ 594 Conjugate (Invitrogen™)

Molecular Probes® fibrinogen conjugates are prepared by attaching fluorescent dye molecules to purified human fibrinogen (approximately 15 dye molecules for each fibrinogen molecule), purifying the conjugate to remove unreacted dye, and then lyophilizing for storage.

Fluorescently labeled fibrinogen has proven to be a valuable tool for investigating platelet activation and subsequent fibrinogen binding. For instance, fluorescein-labeled fibrinogen has been used to detect fibrinogen bound to activated platelets by flow cytometry.

Human Fibrinogen Conjugate Specifications:
• Label (Ex/Em): Alexa Fluor® 594 (~590/617 nm)
• Spectrally similar to Texas Red® dye conjugates, but brighter
• Lyophilized product can be dissolved in buffer (e.g., sodium bicarbonate, pH 8.3) for use
• Fluorescence is typically detected using fluorescence microscopy or flow cytometry


Find More Probes for Cell Adhesion and Receptor Binding
Review Probes for Cell Adhesion, Chemotaxis, Multidrug Resistance and Glutathione—Section 15.6 and Probes for Following Receptor Binding and Phagocytosis—Section 16.1 in the Molecular Probes® Handbook for more information on these probes.

For Research Use Only. Not for human or animal therapeutic or diagnostic use.

5-Dodecanoylaminofluorescein (Invitrogen™)

The lipophilic fluorescein probe, 5-dodecanoylaminofluorescein contains a C12 alkyl chain that will bind to membranes with the fluorophore at the aqueous interface and the alkyl tail protruding into the lipid interior. Lipophilic fluorescein probes are commonly utilized for fluorescence recovery after photobleaching (FRAP) measurements of lipid lateral diffusion.