Poly(amino acid)-polyester graft copolymer nanoparticles for the acid-mediated release of doxorubicin

Biodegradable polymers have emerged as highly effective drug delivery vehicles. We combine N-carboxyanhydride and O-carboxyanhydride ring opening polymerisations to synthesise a poly(amino acid)-polyester graft copolymer capable of encapsulating, and subsequently releasing doxorubicin via acid-mediated hydrolysis. Consequently, the nanoparticles detailed are extremely promising vehicles for the controlled delivery of chemotherapeutic agents

Polymer Hydrogels for Glutathione-Mediated Protein Release

The use of amine-terminated poly(ethylene glycol) star polymers as macroinitiators for the N-carboxyanhydride ring-opening polymerisation of S-tert-butylmercapto-L-cysteine N-carboxahydride is described to yield amphiphilic copolymers that are capable of forming discrete particles in aqueous solution. Poly(amino acid) deprotection liberates the pendant thiol groups that can then form covalent disulfide crosslinks with adjacent thiol groups and yield a crosslinked polymer that is capable of hydrogel formation. The model protein albumin–fluorescein isothiocyanate conjugate was encapsulated within the hydrogels produced, prior to its release upon hydrogel interaction with the reducing agent glutathione. Consequently, the stimuli-responsive polymers formed hold great promise as biomaterials capable of releasing a protein molecular cargo upon interaction with glutathione

The formation of biodegradable micelles from a therapeutic initiator for enzyme-mediated drug delivery.

The direct grafting of amphiphilic macromolecules by sequential n-carboxyanhydride ring-opening polymerisation (NCA ROP) from a therapeutic initiator enables the formation of monodisperse drug-containing micelles. The subsequent enzyme-mediated hydrolysis of the peptide component permits the programmed release of the encapsulated drug molecules, demonstrating a controlled drug delivery platform that negates any challenging payload loading procedures