5(6)-TAMRA NHS Ester (5(6)-Carboxytetramethylrhodamine, TMR, TRITC) is a bright orange-fluorescent dye with excitation ideally suited to the 532 nm or 546 nm laser lines. It has been used widely for preparing peptide, protein, nucleotide and nucleic acid conjugates, especially fluorescent antibodies and avidin derivatives used in immunochemistry. The absorbance and emission maxima of TAMRA conjugates are 553 nm and 575 nm respectively.
TAMRA NHS Ester reacts specifically and efficiently with a primary amine (e.g., side chain of lysine residues or aminosilane-coated surfaces) at pH 7-9 to form a stable, covalent amide bond. The NHS ester (or succinimidyl ester) is the most popular tool for conjugating dyes to the primary amines of protein or antibody (Lys), amine-modified oligonucleotides, and other amine-containing molecules.