EFFECT OF ALUMINUM IONS ON LIPOSOMAL MEMBRANES AS DETECTED BY LAURDANFLUORESCENCE

We report here an investigation of the influence of aluminium on iron- induced peroxidation in brain model membranes. Laurdan fluorescence em ission spectra and generalised polarisation measurements have been use d to investigate how ferrous and aluminium ions can affect the phase c omponents of phospholipid membranes. An increase in the generalised po larisation of oxidised liposomes with respect to controls has been obs erved, which reveals the presence of a less polar environment surround ing the probe that changes the properties of the bilayer. Aluminium ha s been shown to facilitate iron-mediated oxidation as detected from em ission fluorescence spectra. However, no quantitative influence has be en calculated relative to general polarisation and derived phase state determinations. The structural influence of aluminium on membranes ma y therefore be less significantly marked than initially expected.