CHARGE-TRANSFER CHROMATOGRAPHIC STUDY OF THE INTERACTION OF ANTIBIOTICS WITH SODIUM DODECYL-SULFATE

The interaction of 29 antibiotics with the anionic surfactant sodium d odecylsulfate (SDS) was studied by charge-transfer reversed-phase chro matography carried out on impregnated silica layers using water-methan ol mixtures as eluents. The hydrophobicity of antibiotics and the rela tive strength of SDS-antibiotic interaction was calculated separately for each antibiotic-SDS pair. SDS interacted with 17 antibiotics where the antibiotic-SDS complex was either more hydrophillic or more hydro phobic than the uncomplexed molecule. The relative strength of interac tion depended considerably on the molecular structure of the antibioti cs. No significant linear correlation was found between the hydrophobi city parameters of antibiotics and their capacity to interact with SDS . Stepwise regression analysis proved that the inductive effect of sub stituents, their electron-withdrawing power and proton-acceptor capaci ty exert a significance influence on the strength of interaction. (C) 1997 Elsevier Science B.V.