congresos y reuniones científicas
Antihemolysis induced by arginine-based surfactants
FAIT, M.E.; HERMET, M.; COMELLES, F.; CLAPÉS. P.; ÁLVAREZ, A.; PRIETO, E.; MORCELLE, S.R.; BAKÁS, L.
Congreso; Latin American Crosstalk in Biophysics and Physiology; 2015
Latin American Federation of Biophysical Societies
Two novel arginine-based cationic surfactants (Bz-Arg-NHC10 and Bz-Arg-NHC12) were synthesized in our laboratory using as biocatalyst papain, an endopeptidase from Carica papaya latex.The CMC, obtained from the intersection of the two linear portions in the plots vs C were 0.23 and 0.085 mM for Bz-Arg-NHC10 and Bz-Arg-NHC12 respectively. Ionic surfactants have higher CMC values compared to non-ionic ones due to the repulsion between the head groups However for Bz-Arg-NHCn, the head group repulsion is counteracted by the additional benzoil group, facilitating the surfactant self assembly. We used in our experiments sheep (SRBC), and human (HBC) erythrocytes due to their differences in protein and lipid composition. SRBC membranes lack of phosphatidylcholine (PC), which is substituted by sphingomyelin (SM). Both surfactants display a biphasic (protective/lytic) behavior upon interaction with the erythrocytes membranes. The most accepted hypothesis for the lytic action is that surfactants are intercalated into the lipid bilayer, leading to cell lysis. On the other hand, the antihemolytic mechanism is based mainly on the idea that the intercalated compound increases either the membrane-area/cell-volume ratio or the stretching capacity of the bilayer, thereby allowing the cell to attain a higher critical hemolytic volume. HC50 was found to be higher than the respective CMC, showing that hemolysis is induced in the presence of aggregates rather than monomers. We found a good correlation between the CMC, HC50 and cAHmax for both surfactants. The lower CMC value correlates with the lower HC50 and the higher cAHmax and pA (antihemolytic potency), i.e., the higher hemolytic activity, the higher antihemolytic potency. Interestingly, HRBC showed negligible volume expansion caused by both surfactants, while a positive correlation was found on SRBC only for Bz-Arg-NHC12.This knowledge, together with a deeper study of the interaction properties of these compounds with skin would make the two novel arginine compounds a promising alternative to commercial cationic surfactants, especially for their use as penetration enhancers in topical formulations.