Molecular orientation and intracellular photometric analysis.

In reference to the article "Chromatographic Analysis of a Mixture of Proteins from Egg White" (Science, 1949, 110, 564), the cation exchange resin Dowex 50 employed in the experiment cited was obtained in February, 1949, from the Microchemical Specialties Company, Berkeley 3, California, under the name of Ion-X, and not from the Dow Chemical Company as reported in the footnote. We have thus far not obtained satisfactory results with a sample of Dowex 50, (24427), obtained from the Dow Chemical Company on August 8, 1949.