Leica, AD-OXA12-25, ATTO Oxa12 Carboxy Fluorescent Label 5 mg

Optical properties
λ abs = 662 nm
ε max = 1.25×10 5 M -1 cm -1
λ fl = 681 nm
n fl = 30 %
τ fl = 1.8 ns
CF 260 = ε 260 /ε max = 0.32
CF 280 = ε 280 / ε max = 0.12
ATTO Oxa12 is a lipophilic variety of ATTO 655 .
Characteristic features of the label are strong absorption, good fluorescence quantum yield, excellent thermal and photo-stability, and outstanding ozone resistance. Absorption and fluorescence are pH-independent in the range pH 2 to 11, used in typical applications.
ATTO Oxa12 shows excellent solubility in polar organic solvents like DMF, DMSO or acetonitrile. ATTO Oxa12 is a cationic dye. After coupling to a substrate the dye carries a net electrical charge of +1. The fluorescence is excited most efficiently in the range 640 - 675 nm . A suitable excitation source is the 647 nm line of the Krypton-Ion laser or a diode-laser emitting at 650 nm.