2Q4 LEO LOEB AND KENNETH C. BLANCHARD. 



dyeing of wool by acid and basic dyes depends upon the hydrogen 

 ion concentration in the staining solution. They explained this 

 effect as due to the influence of the H and OH ions of the solution 

 on the electrostatic charges of the wool, which latter determine 

 the tendency of the substance to combine with dyes of the opposite 

 charge. They assume this combination to be one of adsorption. 

 Bethe 7 and Rohde 8 apply similar conceptions to the staining of 

 living cells. According to these authors the reaction within the 

 cell determines whether the cells stain with acid or basic stain, 

 and the combination between dye and constituents of the cells 

 has the character of an adsorption. These conceptions are in 

 contrast to those of others who assume that the effect of salts, 

 acids and alkalies on vital staining depends either on the effect 

 of these substances on the permeability of the cell for dyes, or, on 

 their effect on the character of the dye itself. While Bethe 

 believes the combination between constituents of the cell and dye 

 to be one of adsorption, Jacques Loeb 9 showed that proteins 

 combine with acid and basic dyes in a way similar to their 

 combination with ordinary acid and alkali; in both cases the 

 combination is of a stcechiometric chemical nature. In ac- 

 cordance with the amphoteric character of proteid, the latter 

 combines with a basic dye in an alkaline solution and with an 

 acid dye in an acid solution. M. Irwin u finds that the entrance 

 of the alkaline dye (cresylblue) into the cell sap of Nitella shows a 

 quantitative relationship to the hydrogen ion concentration of 

 the surrounding fluid, and that these relations can be expressed in 

 an equation characteristic of a monomolecular reaction. She 

 interprets these findings as indicating a chemical combination 

 between the dye and a protein constituent in the cell sap. 



Our experiments show that the reaction of the fluid surrounding 

 the stained tissue determines whether the stain remains fixed to 

 the tissue, or, whether it leaves the tissue. We furthermore found 

 that these effects are the same irrespective of the tissue con- 

 stituent W 7 ith which the stain had previously combined; it 

 applies in the case of the combination of neutral red with the 



7 A. Bethe, Biochem. Zeitschr., 1922, Bd. 127, 18. 



8 K. Rohde, PJliiger's Archiv., 1917, Bd. 168, 411. 



9 Jacques Loeb, "Proteins and the Theory of Colloidal Behavior," New York, 

 1922. 



10 Marian Invin, Journ. Gen. Physiol., 1923, V., 727. 



