Interestingly, preincubation
of liposomes with the same polymer lacking the alkyl chain
does not induce pH-triggered liposomal leakage (Fig. 2A, b).
This indicates that the presence of alkyl chains in the structure
of the copolymer is essential for liposome pH-dependent response,
possibly due to e¤cient complexation of the polymer
to the liposome membrane via octadecyl chains, as previously
shown for similar systems [14,15]. Acidic-mediated liposome
leakage was only slightly enhanced (about 15%) by increasing
the ODA-containing polymer to lipid mass ratio by a factor
of two (Fig. 2A, c,d), suggesting a binding saturation process
of the polymer to the liposome surface