then analyzed spectrophotometrically at wavelength of 250 nm (according to the method of
drug assay). The amount of drug released was calculated from the standard curve. This procedure was performed in triplicates for each formulation. Cumulative % drug released were calculated out and plotted against time. ALA release from cubosomes in gels has been shown to be primarily controlled by diffusion through the matrix [18] and consequently can be described by the Higuchi diffusion equation given by