mixed isomers

Rhodamine B isothiocyanate (RITC) is a cell-permeant fluorogenic dye most often used as a conjugate to antibodies and proteins for fluorescence detection in microscopy. It displays excitation emission maxima of 570 595 nm, respectively, and can be used in conjunction with immunohistochemistry for multi-labeling studies. It has also been used as an anterograde and retrograde tracer in neurons and in nanoparticles to detect apoptosis.

5(6)-CR110 [5-(and 6)-Carboxyrhodamine 110] *Mixed isomers* is a Fluorescein for peptide and oligonucleotide labeling. Compared to fluorescein labeling reagents such as FITC and FAM, CR110 reagents give more photostable and pH-independent bioconjugates that have the absorption maximum around the preferred 488 nm excitation wavelength. They are photostable alternative reagents superior to FITC and FAM.

5(6)-CR110, SE [5-(and 6)-Carboxyrhodamine 110, succinimidyl ester] *Mixed isomers* is a Fluorescein for peptide and oligonucleotide labeling. Compared to fluorescein labeling reagents such as FITC and FAM, CR110 reagents give more photostable and pH-independent bioconjugates that have the absorption maximum around the preferred 488 nm excitation wavelength. They are photostable alternative reagents superior to FITC and FAM.

5(6)-TAMRA contains a carboxylic acid that can be used to react with primary amines via carbodiimide activation of the carboxylic acid. This bright, orange-fluorescent dye produces conjugates with absorption emission maxima of ~555 580 nm.

ROX dyes have a strong red fluorescence.Their excitation and emission wavelengths are longer than those of traditional rhodamine dyes.They are used as labels for peptides, proteins, and other biological ligands.5-ROX, 6-ROx, and their mixture of 5(6) -RoX

5(6)-TRITC [Tetramethylrhodamine-5-(and-6) -Isothiocyanate] *Mixed isomers* is used to label antibodies with strong fluorescent dyes

5(6)-Carboxyfluorescein (5-(and-6)-Carboxyfluorescein mixed isomers) contains a carboxylic acid that can be used to react with primary amines via carbodiimide activation of the carboxylic acid.

5(6)-Aminofluorescein (5(6)-AFM) is a high-purity, high-quality chemical utilized as a molecular probe and a significant fluorescent agent.

5(6)-FAM SE (5(6)-Carboxyfluorescein N-hydroxysuccinimide ester) is an amine-reactive green fluorescent dye. 5(6)-FAM SE is widely used for labeling proteins or other molecules that contain a primary or secondary aliphatic amine.

Difluorocarboxyfluorescein NHS Ester, 6-isomer, is a fluorescent analogue of fluorescein that reacts with amines. It addresses several limitations of fluorescein, offering enhanced photostability and a lower pKa (~4.7 compared to fluorescein's 6.4), resulting in fluorescence that remains largely pH-insensitive within physiological ranges. Although mixed isomers of difluorocarboxyfluorescein NHS ester are often used as routine fluorescent dyes for labeling proteins, peptides, and nucleotides, purifying peptides and nucleotides labeled with the 5(6) isomer can be challenging due to signal broadening during HPLC purification. Peptides and nucleotides labeled with a single isomer typically show improved resolution in HPLC purification, which is often necessary during conjugation processes.

5(6)-ROX, SE is an amine-reactive fluorescent probe that is widely used for oligonucleotide labeling and automated DNA sequencing applications.