Dr. Kiernan or any interested other:

We are using Alizarin red stain as a colorimetric indicator of Ca++ in
cultured osteoblasts. I was thinking perhaps we could describe the extracted
and spectrophotometrically quantified alizarin (acidified and read at 450
nm) in terms of an equivalent molar concentration of calcium. Further, by
looking up the chemical structure in Conn's, I surmise the equivalence ratio
would be 1 mole Alizarin per 2 moles Calcium. Do you concur?

Donna Montague, M.S.
Research Associate
Physiology/Biophysics and Orthopaedic Surgery
University of Arkansas for Medical