CORE-ANCHORED POLYMERIC NANOCARRIERS

Polymers play a major role in pharmaceutical and drug delivery by providing flexible platforms for controlled release and targeting. The poor aqueous solubility and the physicochemical stability of many drugs is one of the most challenging issues in pharmaceutical development. Polymeric micelles (PMs) are largely used for increasing the solubility of drugs and more recently their oral bioavailability (1). However, a main challenge is preventing the disassembly of PMs under dilution in the body fluids, which leads to uncontrolled release of the encapsulated cargo. We are investigating a new amphiphile architecture, namely core-anchored PMs, to improve the physical stability and performance of these nanocarriers. In this framework, cyclodextrins, an oligocyclic saccharide were used as molecular anchor for the conjugation of amphipathic oligomeric chains made of hydrophobic oligo(epsilon-caprolactone) and 2-(2-methoxyethoxy)ethoxy]acetic acid as hydrophilic capping agent. Characterization was conducted by ¹H-NMR, FTIR and GPC showed that the planed design was successfully obtained, dynamic light scattering was used to test the size and the stability of aggregates in water and rifampin as model drug. Preliminary results are promising. Further studies are being now oriented to use polymeric ethylene glycol derivatives (e.g., poly(ethylene glycol)) and other anchors.

References

1. Sosnik A, Temperature- and pH-sensitive polymeric micelles for drug encapsulation, release and targeting, In: Smart Materials for Drug Delivery, Alvarez-Lorenzo C, Concheiro A (Eds.), Royal Society of Chemistry, London, Chapter 5, pp. 115-147 (2013).