Properties and Biological Behaviour of Coomassie Blue.

The demonstration by Hamilton et al. (1948) and Werko et al. (1949) that the analysis of timeconcentration curves of intravenously injected Evans Blue (T-1824) gave estimates of the cardiac output in man that corresponded closely with those obtained by the direct Fick method stimulated a widespread use of the dye method. However, those properties of Evans Blue that led Dawson et al. (1920) to select it from some 60 dyes as a plasma volume indicator, in particular its affinity for protein and the persistence of tissue coloration, detract from its value in studies of the circulation, especially if repetition of observations is required. Alternative indicators have been widely sought, but none can yet be regarded as wholly satisfactory. In a new attempt to find a solution to the problem the distribution and fate in vivo of some 50 compounds were examined in preliminary animal experiments. As a result the dye, Coomassie Blue, was selected for more detailed examination, the results of which are here reported.