A method for determining the concentration of Photofrin(R) in tissues
and biological fluids was developed. The procedure is based on the dis
solution of biological material with Solvable(R), a commercially avail
able tissue solubilizer, followed by porphyrin-specific fluorescence d
etection and measurement. It was found necessary to use a quadratic st
andard curve for the estimation of unknown Photofrin(R) concentrations
. While this method is limited to compounds that are stable in strong
base, it has the advantages of being sensitive, rapid and low cost.