AttoPhos® AP Fluorescent Substrate System Technical Bulletin

Instructions for Use of Product(s)
S1000, S1001
Literature # TB280

The AttoPhos® AP Fluorescent Substrate System provides a highly sensitive fluorescent alkaline phosphatase substrate. The system includes AttoPhos® Substrate, AttoPhos® Buffer and Calibration Solution. AttoPhos® Substrate (2′-[2-benzothiazoyl]-6′-hydroxybenzothiazole phosphate [BBTP]) is cleaved by alkaline phosphatase to produce inorganic phosphate (Pi) and the alcohol, 2′-[2-benzothiazoyl]-6´-hydroxybenzothiazole (BBT).
This enzyme-catalyzed conversion of the phosphate form of AttoPhos® Substrate to BBT is accompanied by an enhancement in fluorescence properties. Relative to AttoPhos® Substrate, BBT has greatly increased quantum efficiency and fluorescence excitation and emission spectra that are shifted well into the visible region. Relative to other fluorometric reporters, the BBT anion has an unusually large Stokes’ shift of 120nm, which leads to lower levels of background fluorescence and higher detection sensitivity.

Printed in USA. Revised 6/09.