Effect of Chloroquine andO,O′-Bis(diethylaminoethyl)hexestrol on Acidic Phospholipid Membranes

Abstract

The amphiphilic drugs chloroquine and O,O''-bis(diethylaminoethyl)hexestrol are able to form complexes with the acidic phospholipid 1,2-dipalmitoyl-sn-glycero-3-phosphoglycerol. The Kd of the complexes with chloroquine are independent of pH in the range investigated here (4-7) as well as of temperature (4.degree.-40.degree. C). The phase transition temperature of phospholipid is markedly reduced by both drugs; the effect is reversible by addition of Ca2+.