Tuning core hydrophobicity of spherical polymeric nanoconstructs for docetaxel delivery

The reformulation of nanoparticles of chemotherapeutic molecules is often required to enhance their bioavailability, increase blood longevity and eventually improve the outcome of the pharmacological intervention. Docetaxel (DTXL), a potent anti-cancer drug daily used for the treatment of different neoplastic diseases, is one of such molecules. Here, spherical polymeric nanoconstructs (SPNs) with a characteristic size of 200nm are designed for the delivery of DTXL. SPNs comprise a hydrophobic polymeric core where the drug is entrapped and are externally stabilized by a lipid monolayer decorated with polyethylene glycol chains. Two different polymers are used for the core formation, namely poly(d,l-lactide-co-glycolic) acid (PLGA), which has been extensively used for similar biomedical applications, and poly(3-hydroxybutyrate) (P(3HB)), which is a natural polymer produced by a wide variety of bacterial species under nutrient limiting conditions. The two nanoformulations of DTXL are compared in terms of loading, release and cytotoxic drug potential. Consistent with the higher hydrophobicity of P(3HB) over PLGA, the former polymer allows for a higher loading efficiency (almost double that of PLGA) and slower release rates. No significant difference is observed in terms of internalization rate and cytotoxicity potential. This work demonstrates that P(3HB) could be a valid alternative to the more conventional PLGA for the delivery and controlled release of hydrophobic therapeutic molecules.