Biological Conjugation

Vari Fluor 594 TSA (200×) (VF 594 Tyramide) is a fluorescent probe belonging to the Vari Fluor TSA series. Vari Fluor TSA series fluorescent probes can be used for high-density in situ labeling of target antigens using horseradish peroxidase (HRP) assays, which are widely used in ELISA, IF, IHC and other techniques with high detection sensitivity.

5-FAM SE is a single isomer, is a fluorescent labeling reagent used for labeling peptides, proteins and nucleotides. 5-FAM SE can react with amines and can yield stable amine conjugates.

BODIPY dye is a small molecule dye with strong ultraviolet absorption ability, its fluorescence peak is relatively sharp, and the quantum yield is high. They are relatively insensitive to the polarity and pH of the environment and are relatively stable under different physiological conditions. Due to its structural asymmetry, BODIPY derives a variety of structural products. BODIPY lipid droplet dyes can well pass through the cell membrane into the cell, and localize the neutral lipids in the cell to specifically stain the lipid droplets, which can be used for labeling of live cells and fixed cells.

4-Methylumbelliferyl-α-D-galactopyranoside (4MU-α-Gal), a substrate for α-galactosidase A (GLA), is a blue pro-fluorogenic substrate. 4-Methylumbelliferyl-α-D-galactopyranoside forms two products, galactose and fluorescent 4MU, upon cleavage by GLA.

Sulfobromophthalein (Bromosulfophthalein) disodium salt is an organic anion dye used in the study of a variety of membrane carriers expressed in animal tissues and involved in transport of agents and metabolites.

Sulfo-Cy5 azide is a near-infrared fluorescent probe with favorable click chemistry reactivity. Sulfo-Cy5 azide enables fluorescence imaging, tissue and cellular visualization of PD-L1 in tumors, and site-specific modification of anti-PD-L1 antibodies. Sulfo-Cy5 azide has been employed for RNA labeling and imaging. Sulfo-Cy5 azide can be conjugated to targeting agents for fluorescence imaging in atherosclerosis and breast cancer models (Ex/Em = 645/670 nm).

Janelia Fluor 646, SE (JF646, SE) is a red fluorescent dye can be used in cellular imaging. Janelia Fluor fluorescent dyes can be chemically conjugated to the specific HaloTag substrate (a chloroalkane ligand) to form a fluorescent ligand, rather than binding directly to the HaloTag protein itself. Janelia Fluor products are licensed under U.S. Pat. Nos. 9,933,417, 10,018,624 and 10,161,932 and other patents from Howard Hughes Medical Institute (Ex/Em = 646/664 nm).

5(6)-TAMRA SE is a fluorescent dye that emits red fluorescence. 5(6)-TAMRA SE binds to oligonucleotides and is used in DNA sequencing. 5(6)-TAMRA SE can be used in cancer research (Ex/Em = 565/580 nm).

Cyanine5 azide chloride is a Fluorescent probe for cell-selective bacterial protein labeling, as well as a fluorescent dye for single-molecule imaging and dynamic tracking of intracellular organelles. Cyanine5 azide chloride can conjugate with the alkynyl side chain of propargylglycine incorporated into bacterial proteins by the engineered methionyl-tRNA synthetase variant PraRS via copper (I)-catalyzed azide-alkyne [3+2] cycloaddition reaction, thereby enabling in-gel fluorescent visualization of labeled proteins. Cyanine5 azide chloride can diffuse across cell membranes and undergo copper-free click reaction with DBCO-functionalized scAVD pre-bound to DBCO-functionalized biotin, forming fluorescent nanoprobes with enhanced brightness, photostability and localization accuracy, and exhibiting discrete photobleaching steps. The excitation wavelength of Cyanine5 azide chloride is Ex = 633 nm.

The Labeling Kits Centrifugation-Based Rapid Desalting Column (5KD) is a laboratory tool for rapid desalting, particularly suitable for the purification and concentration of proteins and other biological molecules. This product utilizes centrifugal force and passes through a specific filter membrane (with a molecular weight cut-off of 5KD) to effectively remove salts and other small molecule impurities from the sample.

BG-NH2 is a pharmaceutical intermediate. BG-NH2 is suitable for synthesizing fluorescent SNAP tag substrates to label RNA.

Cyanine7 DBCO (Cy7 DBCO) is a near-infrared fluorescent dye and an efficient bio-orthogonal quencher. Cyanine7 DBCO is formed by covalent connection of the near-infrared fluorescent dye Cy7 and the dibenzocyclooctyne (DBCO) functional group. After reacting with N3-Cy5-COOH, the fluorescence of Cy5 decreases by 90% within 90 minutes, and rapid signal attenuation can be observed within 2-5 minutes. Cyanine7 DBCO can be used for the study of deep tissue imaging and receptor-targeted therapeutic strategies.

5-DTAF is a fluorescein dye that directly react with polysaccharides and other alcohols in aqueous solution at pH ＞9. The maximum of the 5-DTAF emission profile is at a wavelength of 518 nm after excitation at 488 nm. 5-DTAF can be used for biomolecular labeling, protein detection, and cell imaging.

6-TAMRA (6-Carboxytetramethylrhodamine) is a fluorescent dye. 6-TAMRA is often used in combination with 6-FAM (HY-66021) as an acceptor or fluorescence quencher for fluorescence resonance energy transfer (FRET) in biochemical studies such as potassium ion detection and ribonuclease activity assays.

7-Amino-4-(trifluoromethyl)coumarin (Coumarin 151) is a fluorescent marker for the sensitive detection of proteinases. The excitation and emission wavelengths are 400 and 490 nm, respectively.

Cyanine 5.5 azide (CY 5.5 azide) is a potent fluorescent dye. Cyanine 5.5 azide can label DNA. Cyanine 5.5 azide can be used for NIR live organism imaging. (λ_ex=684 nm, λ_em=710 nm). Cyanine 5.5 azide is a click chemistry reagent, it contains an Azide group and can undergo copper-catalyzed azide-alkyne cycloaddition reaction (CuAAc) with molecules containing Alkyne groups. It can also undergo strain-promoted alkyne-azide cycloaddition (SPAAC) reactions with molecules containing DBCO or BCN groups.

Cy3-N3 is a Cy3-azide fluorescent dye used to label for protein and nucleic acid. Cy3-N3 is a click chemistry reagent, it contains an Azide group and can undergo copper-catalyzed azide-alkyne cycloaddition reaction (CuAAc) with molecules containing Alkyne groups. It can also undergo strain-promoted alkyne-azide cycloaddition (SPAAC) reactions with molecules containing DBCO or BCN groups (Ex/Em = 548/563 nm).

Cyanines are formally compounds with two nitrogen atoms linked by an odd number of methene units. 26 28 The nitrogen atoms are parts of the heterocyclic units (such as indole, benzoxazol, or benzothiazol) . The structures and optical properties of representative cyanine dyes used for in vivo imaging are presented. Cyanines are characterized by long wavelength, tunable absorption and emission, very high extinction coefficient (up to 300,000 M 1 cm 1), good water solubility, and relatively straightforward synthesis.

Naph-EA-mal (Thiol-green 1) is a rapid detect and ultrafast turn-on thiol fluorescence probe for protein labeling and bioimaging. Naph-EA-mal (Thiol-green 1) can be used to detect thiols in living cells, label the protein thiols, quantify the concentration of total thiols in cell lysate, and determine the reversible protein thiols oxidation in fixed cells. Ex: 488 nM; Em: 540 nM.

BODIPY 576/589 is a long wavelength biological labeled dye contains a free COOH-group (Em/Ex = 589/576 nm).