Interaction of 3,7-diamino-2,8-dimethyl-5-phenyl phenazinium chloride with model biological membranes and reverse micelles of lipid: a spectroscopic study

The interaction of 3,7-diamino-2,8-dimethyl-5-phenyl phenazinium chloride (Safranine T) with the aqueous as well as reverse micellar solution of a phospholipid 1,2-diacyl-sn-glycero-3-phosphocholine (Azolecithin), a major structural phospholipid in brain, comprising approx 15% of total lipid, primarily localized in grey matter have been studied by absorption and fluorescence spectroscopic studies. The results show the evidence of complex formation of the dye in the ground and in the excited state. The interaction of the dye with the lipid in reverse micellar state is more compared to that in liposomes. An attempt has been made to determine the polarity of the microenvironment of the dye in liposomes or reverse micelles from the spectral studies of the dye in different solvents of known polarity. The polarity functions of the phosphatidylcholine (PC) liposomes are slightly lower compared to that of PC reverse micelles.