A New Chemical Method for Measuring Cell Populations in Tissue Cultures.

Abstract

Tissue culture populations can be measured quantitatively by their "total purine and pyrimidine" content (TPP). The TPP determination involves extraction of washed cells with a hot acid saline solution and reading the absorbance of the extract at 268 m[mu]. The method avoids interference by amino acids and proteins, and appears to be specific for purines and pyrimidines. TPP is at least as good as protein nitrogen as a measure of cell populations. The TPP method has operational advantages over protein methods.