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Lectin PNA From Arachis hypogaea (peanut), Alexa Fluor™ 647 Conjugate Invitrogen™

Lectin PNA is specific for terminal β-galactose. It will agglutinate human erythrocytes, but only after neuraminidase treatment.[ALTREF PN40265]

Dextran, Tetramethylrhodamine and biotin, 10,000 MW, Lysine Fixable (mini-Ruby) Invitrogen™

Labeled dextrans are hydrophilic polysaccharides most commonly used in microscopy studies to monitor cell division, track the movement of live cells, and to report the hydrodynamic properties of the cytoplasmic matrix. The labeled dextran is commonly introduced into the cells via microinjection.

Need a different emission spectrum or longer tracking? View our other mammalian cell tracking products.

Dextran Specifications:

Label (Ex/Em): Tetramethylrhodamine & Biotin (555/580)
Size: 10,000 MW
Charge: Anionic
Fixable: Fixable via Lysine

High Manufacturing Standards of Molecular Probes® Dextrans
We offer more than 50 fluorescent and biotinylated dextran conjugates in several molecular weight ranges. Dextrans are hydrophilic polysaccharides characterized by their moderate-to-high molecular weight, good water solubility, and low toxicity. They also generally exhibit low immunogeniticy. Dextrans are biologically inert due to their uncommon poly-(α-D-1,6-glucose) linkages, which render them resistant to cleavage by most endogenous cellular glycosidases.

In most cases, Molecular Probes® fluorescent dextrans are much brighter and have higher negative charge than dextrans available from other sources. Furthermore, we use rigorous methods for removing as much unconjugated dye as practical, and then assay our dextran conjugates by thin-layer chromatography to help ensure the absence of low molecular weight contaminants.

A Wide Selection of Substituents and Molecular Weights
Molecular Probes® dextrans are conjugated to biotin or a wide variety of fluorophores, including seven of our Alexa Fluor® dyes (Molecular Probes dextran conjugates–Table 14.4) and are available in these nominal molecular weights (MW): 3,000; 10,000; 40,000; 70,000; 500,000; and 2,000,000 daltons.

Dextran Net Charge and Fixability
We employ succinimidyl coupling of our dyes to the dextran molecule, which, in most cases, results in a neutral or anionic dextran. The reaction used to produce the Rhodamine Green™ and Alexa Fluor® 488 dextrans results in the final product being neutral, anionic, or cationic. The Alexa Fluor®, Cascade Blue®, lucifer yellow, fluorescein, and Oregon Green® dextrans are intrinsically anionic, whereas most of the dextrans labeled with the zwitterionic rhodamine B, tetramethylrhodamine, and Texas Red® dyes are essentially neutral. To produce more highly anionic dextrans, we have developed a proprietary procedure for adding negatively charged groups to the dextran carriers; these products are designated "polyanionic" dextrans.

Some applications require that the dextran tracer be treated with formaldehyde or glutaraldehyde for subsequent analysis. For these applications, we offer "lysine-fixable" versions of most of our dextran conjugates of fluorophores or biotin. These dextrans have covalently bound lysine residues that permit dextran tracers to be conjugated to surrounding biomolecules by aldehyde-mediated fixation for subsequent detection by immunohistochemical and ultrastructural techniques. We have also shown that all of our 10,000 MW Alexa Fluor® dextran conjugates can be fixed with aldehyde-based fixatives.

Key Applications Using Labeled Dextrans
There are a multitude of citations describing the use of labeled dextrans. Some of the most common uses include:

Neuronal tracing (anterograde and retrograde) in live cells
Cell lineage tracing in live cells
Neuroanatomical tracing
Examining intercellular communications (e.g., in gap junctions, during wound healing, and during embryonic development)
Investigating vascular permeability and blood–brain barrier integrity
Tracking endocytosis
Monitoring acidification (some dextran–dye conjugates are pH-sensitive)
Studying the hydrodynamic properties of the cytoplasmic matrix

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

FL - eA2 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.

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.

Biotin-X DHPE (N-((6-(Biotinoyl)amino)hexanoyl)-1,2-Dihexadecanoyl-sn-Glycero-3-Phosphoethanolamine, Triethylammonium Salt) Invitrogen™

The biotinylated phospholipid, biotin-X DHPE can be used to couple avidin or streptavidin to cell membranes, liposomes and lipoid monolayers.

Lectin HPA From Helix pomatia (edible snail), Alexa Fluor™ 488 Conjugate Invitrogen™

Lectin Helix pomatia agglutinin (HPA) selectively binds to α-N-acetylgalactosamine residues and type A erythrocytes.

Dextran, Texas Red™, 3000 MW, Lysine Fixable Invitrogen™

Labeled dextrans are hydrophilic polysaccharides most commonly used in microscopy studies to monitor cell division, track the movement of live cells, and to report the hydrodynamic properties of the cytoplasmic matrix. The labeled dextran is commonly introduced into the cells via microinjection.

Need a different emission spectrum or longer tracking? View our other mammalian cell tracking products.

Dextran Specifications:

Label (Ex/Em): Texas Red® (595/615)
Size: 3,000 MW
Charge: Zwitterionic
Fixable: Fixable via Lysine

High Manufacturing Standards of Molecular Probes® Dextrans
We offer more than 50 fluorescent and biotinylated dextran conjugates in several molecular weight ranges. Dextrans are hydrophilic polysaccharides characterized by their moderate-to-high molecular weight, good water solubility, and low toxicity. They also generally exhibit low immunogeniticy. Dextrans are biologically inert due to their uncommon poly-(α-D-1,6-glucose) linkages, which render them resistant to cleavage by most endogenous cellular glycosidases.

In most cases, Molecular Probes® fluorescent dextrans are much brighter and have higher negative charge than dextrans available from other sources. Furthermore, we use rigorous methods for removing as much unconjugated dye as practical, and then assay our dextran conjugates by thin-layer chromatography to help ensure the absence of low molecular weight contaminants.

A Wide Selection of Substituents and Molecular Weights
Molecular Probes® dextrans are conjugated to biotin or a wide variety of fluorophores, including seven of our Alexa Fluor® dyes (Molecular Probes dextran conjugates–Table 14.4) and are available in these nominal molecular weights (MW): 3,000; 10,000; 40,000; 70,000; 500,000; and 2,000,000 daltons.

Dextran Net Charge and Fixability
We employ succinimidyl coupling of our dyes to the dextran molecule, which, in most cases, results in a neutral or anionic dextran. The reaction used to produce the Rhodamine Green™ and Alexa Fluor® 488 dextrans results in the final product being neutral, anionic, or cationic. The Alexa Fluor®, Cascade Blue®, lucifer yellow, fluorescein, and Oregon Green® dextrans are intrinsically anionic, whereas most of the dextrans labeled with the zwitterionic rhodamine B, tetramethylrhodamine, and Texas Red® dyes are essentially neutral. To produce more highly anionic dextrans, we have developed a proprietary procedure for adding negatively charged groups to the dextran carriers; these products are designated "polyanionic" dextrans.

Some applications require that the dextran tracer be treated with formaldehyde or glutaraldehyde for subsequent analysis. For these applications, we offer "lysine-fixable" versions of most of our dextran conjugates of fluorophores or biotin. These dextrans have covalently bound lysine residues that permit dextran tracers to be conjugated to surrounding biomolecules by aldehyde-mediated fixation for subsequent detection by immunohistochemical and ultrastructural techniques. We have also shown that all of our 10,000 MW Alexa Fluor® dextran conjugates can be fixed with aldehyde-based fixatives.

Key Applications Using Labeled Dextrans
There are a multitude of citations describing the use of labeled dextrans. Some of the most common uses include:

Neuronal tracing (anterograde and retrograde) in live cells
Cell lineage tracing in live cells
Neuroanatomical tracing
Examining intercellular communications (e.g., in gap junctions, during wound healing, and during embryonic development)
Investigating vascular permeability and blood–brain barrier integrity
Tracking endocytosis
Monitoring acidification (some dextran–dye conjugates are pH-sensitive)
Studying the hydrodynamic properties of the cytoplasmic matrix

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

β-Py-C10-HPC (1-Hexadecanoyl-2-(1-Pyrenedecanoyl)-sn-Glycero-3-Phosphocholine) Invitrogen™

This phospholipid analog of phosphocholine, ß-py-C10-HPC is labeled with pyrene on the sn-2 acyl chain. Pyrene forms excimers at high concentrations, excimer emission ~470nm. Pyrene is environment sensitive, essentially nonfluorescent in water.

FL - TB3 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.

Dextran, Texas Red™, 40,000 MW, Neutral Invitrogen™

Labeled dextrans are hydrophilic polysaccharides most commonly used in microscopy studies to monitor cell division, track the movement of live cells, and to report the hydrodynamic properties of the cytoplasmic matrix. The labeled dextran is commonly introduced into the cells via microinjection.

Need a different emission spectrum or longer tracking? View our other mammalian cell tracking products.

Dextran Specifications:

Label (Ex/Em): Texas Red® (595/615)
Size: 40,000 MW
Charge: Zwitterionic
Fixable: Nonfixable

High Manufacturing Standards of Molecular Probes® Dextrans
We offer more than 50 fluorescent and biotinylated dextran conjugates in several molecular weight ranges. Dextrans are hydrophilic polysaccharides characterized by their moderate-to-high molecular weight, good water solubility, and low toxicity. They also generally exhibit low immunogeniticy. Dextrans are biologically inert due to their uncommon poly-(α-D-1,6-glucose) linkages, which render them resistant to cleavage by most endogenous cellular glycosidases.

In most cases, Molecular Probes® fluorescent dextrans are much brighter and have higher negative charge than dextrans available from other sources. Furthermore, we use rigorous methods for removing as much unconjugated dye as practical, and then assay our dextran conjugates by thin-layer chromatography to help ensure the absence of low molecular weight contaminants.

A Wide Selection of Substituents and Molecular Weights
Molecular Probes® dextrans are conjugated to biotin or a wide variety of fluorophores, including seven of our Alexa Fluor® dyes (Molecular Probes dextran conjugates–Table 14.4) and are available in these nominal molecular weights (MW): 3,000; 10,000; 40,000; 70,000; 500,000; and 2,000,000 daltons.

Dextran Net Charge and Fixability
We employ succinimidyl coupling of our dyes to the dextran molecule, which, in most cases, results in a neutral or anionic dextran. The reaction used to produce the Rhodamine Green™ and Alexa Fluor® 488 dextrans results in the final product being neutral, anionic, or cationic. The Alexa Fluor®, Cascade Blue®, lucifer yellow, fluorescein, and Oregon Green® dextrans are intrinsically anionic, whereas most of the dextrans labeled with the zwitterionic rhodamine B, tetramethylrhodamine, and Texas Red® dyes are essentially neutral. To produce more highly anionic dextrans, we have developed a proprietary procedure for adding negatively charged groups to the dextran carriers; these products are designated "polyanionic" dextrans.

Some applications require that the dextran tracer be treated with formaldehyde or glutaraldehyde for subsequent analysis. For these applications, we offer "lysine-fixable" versions of most of our dextran conjugates of fluorophores or biotin. These dextrans have covalently bound lysine residues that permit dextran tracers to be conjugated to surrounding biomolecules by aldehyde-mediated fixation for subsequent detection by immunohistochemical and ultrastructural techniques. We have also shown that all of our 10,000 MW Alexa Fluor® dextran conjugates can be fixed with aldehyde-based fixatives.

Key Applications Using Labeled Dextrans
There are a multitude of citations describing the use of labeled dextrans. Some of the most common uses include:

Neuronal tracing (anterograde and retrograde) in live cells
Cell lineage tracing in live cells
Neuroanatomical tracing
Examining intercellular communications (e.g., in gap junctions, during wound healing, and during embryonic development)
Investigating vascular permeability and blood–brain barrier integrity
Tracking endocytosis
Monitoring acidification (some dextran–dye conjugates are pH-sensitive)
Studying the hydrodynamic properties of the cytoplasmic matrix

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

Pierce™ Horseradish Peroxidase, Biotinylated Thermo Scientific™

Thermo Scientific Pierce Biotinylated Proteins include biotin-labeled proteins (BSA), enzymes (HRP, AP) and fluorophores (FITC) for use as controls or signal amplification in IHC via avidin-biotin complex (ABC) techniques.

Biotinylated HRP is most commonly used in immunohistochemistry (IHC) to amplify the signal of biotinylated primary antibodies using the ABC staining method.

Biotinylated enzymes—biotin-labeled horseradish peroxidase (B-HRP), alkaline phosphatase (B-AP) and beta-galactosidase (B-bGal) for use in avidin-biotin complex (ABC) staining

Biotin, also known as vitamin H, is a small molecule (MW 244.3) that is present in tiny amounts in all living cells and is critical for a number of biological processes. The valeric acid side chain of the biotin molecule can be derivatized in order to incorporate various reactive groups that are used to attach biotin to other molecules. In the context of immunohistochemistry (IHC), biotin is conjugated to antibodies or to the enzyme reporters used to detect target antigens.

Related Products
Pierce™ Bovine Serum Albumin, Biotinylated
Pierce™ Alkaline Phosphatase, Biotinylated
Pierce™ Biotin-Fluorescein Conjugate
Pierce™ Biotin

CaptureSelect™ Biotin Anti-Gonadotropin Conjugate Thermo Scientific™

CaptureSelect™ Biotin Anti-Gonadotropin Conjugate consists of a 13 kDa camelid antibody fragment (affinity ligand) that specifically binds with high affinity and selectivity to the alpha chain of human gonadotropins. This group of human glycoprotein hormones includes human chorionic gonadotropin (HCG), luteinizing hormone (LH), thyroid-stimulating hormone (TSH), and follicle-stimulating hormone (FSH), which all possess an identical alpha chain subunit . 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 gonadotropins.

Applications for CaptureSelect Biotin Anti-Gonadotropin Conjugate include ELISA, immunoprecipitation with streptavidin-coupled Dynabeads™, Gyrolab™-based immunoassays, and label-free detection using platforms such as those based on surface plasmon resonance (Biacore™ and IBIS-MX96 systems) and bio-layer interferometry (ForteBio™ Octet™ systems).

Gelatin From Pig Skin, Oregon Green™ 488 Conjugate Invitrogen™

Molecular Probes® fluorescent conjugates of gelatin are designed for researchers studying not only collagen-binding proteins and collagen metabolism, but also for the study of gelatinases and collagenases (metalloproteins that digest collagen and gelatin). We offer two fluorescent conjugates of gelatin—one in which gelatin is coupled to fluorescein (G13187) and the other in which gelatin is coupled to our Oregon Green® 488 dye (G13186).

Gelatin Conjugate Specifications:
• Label (Ex/Em): Oregon Green® 488 (~499/519 nm)
• Degree of labeling is listed on the product label (based on molecular weight of 100,000)


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

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

Griffonia Simplicifolia (African Legume) Lectin I (GSL I), DyLight 594 Invitrogen™

Griffonia Simplicifolia Lectin I (GSL I-B4), DyLight 594, is a bright red GSL I-B4-fluorophor conjugate that is sourced from the African legume Griffonia simplicifolia (Bandeiraea simplicifolia). This B4 isoform of GSL I contains only B subunits and is widely used as a marker of endothelial cells in non-primates such as mouse, rat, rabbit, and goat, as well as a marker of non-peptidergic unmyelinated primary afferent neurons.

• Very bright DyLight 594 conjugate detected with traditional Texas Red filter set, Ex/Em: 592/617 nm
• Applications: immunofluorescence, glycobiology
• Sugar specificity: galactose
• Inhibiting/eluting sugar: 500 mM galactose (S-9003) or 100 mM raffinose
• Blood group specificity: B>>A1
• Unconjugated lectin molecular weight: 114 KDa
• Immunofluorescence working concentration: 5–20 µg/mL

GSL I-B4-DyLight 594 is provided at a 1 mg/mL concentration in 10 mM HEPES, 0.15 M NaCl, pH 7.5, 0.08% sodium azide, 0.1 mM Ca2+. If a precipitate forms upon long-term storage, warm to 37°C.

GSL I is a tetrameric lectin consisting of A and B subunits. There are five GSL-I isolectins with different subunit compositions. The B4 isolectin (all B subunits) is blood-group-B specific and has an exclusive affinity for terminal α-D-galactosyl residues. It specifically agglutinates blood group B erythrocytes and was originally employed for this purpose. Subsequent work has shown that the GSL I B4 isolectin is cytotoxic to several normal and tumor cell types and has particularly strong affinity for brain microglial and perivascular cells. It has also been particularly valuable as a histochemical and flow cytometric probe for specifically labeling endothelial cells in a number of species. GSL I B4 isolectin has been used effectively for tracing central and peripheral neuronal pathways following local injections, as well as for labeling stimulated murine macrophages, bovine thyroid cells, various murine cell types, laminin, and thyroglobulin.

Transferrin From Human Serum, Fluorescein 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): Fluorescein (495/518)

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.
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