title: The Effect of Branching (Star Architecture) on Poly(d,l-lactide) (PDLLA) Degradation and Drug Delivery.
abstract: This study focuses on the comparative evaluation of star (branched) and linear poly(l,d-lactic acid) (PDLLA) as degradable materials employed in controlled release. The polymers were prepared via ring-opening polymerization initiated by decanol (linear), pentaerythritol (4-armed star) and dipentaerythritol (6-armed star), and processed both in the form of films and nanoparticles. Independent of the length or number of their arms, star polymers degrade slower than linear polymers, possibly through a surface (vs bulk) mechanism. Further, the release of a model drug (atorvastatin) followed zero-order-like kinetics for the branched polymers, and first-order kinetics for linear PDLLA. Using NHOst osteoblastic cells, both linear and star polymers were devoid of any significant toxicity and released atorvastatin in a bioavailable form; cell adhesion was considerably lower on star polymer films, and the slower release from their nanoparticles appeared to be beneficial to avoid atorvastatin overdosing.
authors.affiliation: NorthWest Centre of Advanced Drug Delivery (NoWCADD), Manchester Pharmacy School, University of Manchester , Oxford Road, Manchester, M13 9PT, United Kingdom.
authors.forename: Jason
authors.initials: J
authors.lastname: Burke
authors.affiliation: NorthWest Centre of Advanced Drug Delivery (NoWCADD), Manchester Pharmacy School, University of Manchester , Oxford Road, Manchester, M13 9PT, United Kingdom.
authors.forename: Roberto
authors.initials: R
authors.lastname: Donno
authors.affiliation: NorthWest Centre of Advanced Drug Delivery (NoWCADD), Manchester Pharmacy School, University of Manchester , Oxford Road, Manchester, M13 9PT, United Kingdom.
authors.forename: Richard
authors.initials: R
authors.lastname: d'Arcy
authors.affiliation: School of Materials, University of Manchester , Grosvenor Street, Manchester, M13 9PL, United Kingdom.
authors.forename: Sarah
authors.initials: S
authors.lastname: Cartmell
authors.affiliation: NorthWest Centre of Advanced Drug Delivery (NoWCADD), Manchester Pharmacy School, University of Manchester , Oxford Road, Manchester, M13 9PT, United Kingdom.
authors.forename: Nicola
authors.identifier: 0000-0002-4879-3949
authors.initials: N
authors.lastname: Tirelli
mesh_terms: D000069059:Atorvastatin / Q000494:pharmacology; D001682:Biological Availability; D002478:Cells, Cultured; D055598:Chemical Phenomena; D016503:Drug Delivery Systems; D065546:Drug Liberation; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D018625:Microscopy, Atomic Force; D008970:Molecular Weight; D053758:Nanoparticles / Q000737:chemistry*; D010006:Osteoblasts / Q000187:drug effects; D011091:Polyesters / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D011091:Polyesters; C033616:poly(lactide); D000069059:Atorvastatin