PEO-b-PCL grafted DPPC liposomes: physicochemical characterization and stability studies of novel bio-inspired advanced Drug Delivery nano Systems (aDDnSs).

Amphiphilic block copolymers and lipids have attracted major scientific interest in recent years due to their intriguing self-assembly behavior, which results in a plethora of nanoassemblies and their potential applications in Pharmaceutical Nanotechnology, as bio-inspired chimeric or hybrid advanced Drug Delivery nano Systems (aDDns). In this work, we report on stability studies of chimeric systems consisted of DPPC (dipalmitoylphosphatidylcholine) and poly(ethylene oxide)-block-poly(ε-caprolactone) (PEO-b-PCL) block copolymer in Phosphate Buffer Saline (PBS) and Fetal Bovine Serum (FBS). The incorporation of PEO-b-PCL leads to bio-inspired nanovectors of smaller size, in comparison to DPPC neat liposomes. All the prepared chimeric liposomal formulations were found to retain their original physicochemical characteristics for at least five days. These nanocarriers could be characterized as stealth liposomes due to their biological stability. The composition of the bio-inspired aDDnSs play a key role on their physicochemical and structural properties, as well as on their biological response, which could be a road map for designing aDDnSs based on the bio-inspiration.