Carboxyfluorescein Leakage Assay

Membrane disruption ability of the furin peptides was determined by examining the release of carboxyfluorescein dye from CF-bound liposomes using the Cary Eclipse fluorescence spectrophotometer (Varian Inc). Basal fluorescence of the CF-bound liposomes was measured by exciting the vesicles at 495 nm and recording the emission fluorescence from 500 to 550 nm. Fluorescence emission spectra in the presence of increasing peptide concentration was also recorded. Change in emission intensity at maxima was then plotted against peptide concentration to examine the CF leakage in the presence of AMPs. The measurements were carried out using a 0.1 cm path length quartz cuvette.