816 L. L. Jansen 



in the region corresponding lo the critical micellar concentration. 

 One can conceive what tremendous effects could result from place- 

 ment of such a solution on the charged surface of a cell wall and 

 how these effects could be transmitted through the aqueous continuum 

 in the cuticle and cell wall to the charged cytoplasmic skeleton. 



Electrophoretic and osmotic properties of surfactant solutions 

 are also modified anomolously as concentration of the surfactant is 

 increased. In Figure IC we see the cation transference numbers for 

 an homologous series of alkyl amine hydrochlorides plotted against 

 concentration of surfactant. Abrupt changes occur in cation transfer 

 after we pass the C-8 moiety. Among higher homologues the magni- 

 tude of the change is increased as chain-length increases to C-14, but 

 thereafter the magnitude is lessened. The effect of concentration 

 of a representative surfactant on the osmotic coefficient, as determined 

 by freezing point depression, is plotted in Figure ID. The osmotic 

 coefficient of surfactant systems is considerably less than predicted 

 values at concentrations commonly employed in industrial and bio- 

 logical work. In the case of the representative surfactant used in the 

 illustration, the breakpoint occurs at a concentration of approxi- 

 mately 0.8 per cent. 



One cannot comment at the present time on the importance of 

 all of these phenomena to the behaviors of biologically active chemi- 

 cals. They are factors, however, which conceivably could materially 

 influence penetration, translocation, and chemical activity. The pur- 

 pose of this presentation has been to draw attention to those factors 

 other than surface tensions which may be influential in the biological 

 activity of systems containing surfactants. 



LITERATURE CITED 



1. Schwartz, A. M., and Perry, J. W. Surface Active Agents. \'ol. I. 579 pp. Inter- 

 science Publisliers, Inc., New York. 1949. 



2. , Perry, J. W., and Berch, J. Surface Active Agents and Detergents. Vol. 



II. 839 pp. Interscience Publishers, Inc., New York. 1958. 



