title: Synthesis and characterisation of cationic quaternary ammonium-modified polyvinyl alcohol hydrogel beads as a drug delivery embolisation system.
abstract: To extend the platform of clinically utilised chemoembolic agents based on ion-exchange systems to support the delivery of anionic drugs, a series of PVA-based beads was produced with different levels of (3-acrylamidopropyl)trimethylammonium chloride (APTA) in their formulation. The beads were characterised to confirm composition and the effect of formulation variation on physical properties was assessed. Suspension polymerisation was shown to successfully produce uniformly spherical copolymer beads with APTA content up to 60 wt%. Equilibrium water content and resistance to compression both increased with increasing APTA content in the formulation. Confocal laser scanning microscopy was used with model drugs to demonstrate that by increasing APTA content, compounds between the molecular weight range 70-250 kDa could permeate the microsphere structures. Interaction with anionic drugs was modelled using multivalent dyes. Dyes with multi-binding sites had increased interaction with the polymer, slowing the release and also demonstrating a reduced rate of elution from beads with higher charge density. The model drug release studies demonstrate that these systems can be engineered for different potential anionic drugs for local therapeutic delivery in the clinic.
authors.affiliation: School of Pharmacy and Biomolecular Sciences, University of Brighton, Moulsecoomb, Brighton, BN2 4GJ, UK. c.heaysman@ucl.ac.uk.|Biocompatibles UK Ltd, Farnham Business Park, Weydon Lane, Farnham, Surrey, GU9 8QL, UK. c.heaysman@ucl.ac.uk.
authors.forename: Clare L
authors.initials: CL
authors.lastname: Heaysman
authors.affiliation: School of Pharmacy and Biomolecular Sciences, University of Brighton, Moulsecoomb, Brighton, BN2 4GJ, UK.
authors.forename: Gary J
authors.initials: GJ
authors.lastname: Phillips
authors.affiliation: School of Pharmacy and Biomolecular Sciences, University of Brighton, Moulsecoomb, Brighton, BN2 4GJ, UK.
authors.forename: Andrew W
authors.initials: AW
authors.lastname: Lloyd
authors.affiliation: Biocompatibles UK Ltd, Farnham Business Park, Weydon Lane, Farnham, Surrey, GU9 8QL, UK. andrew.lewis@biocompatibles.com.
authors.forename: Andrew L
authors.initials: AL
authors.lastname: Lewis
mesh_terms: D000818:Animals; D004396:Coloring Agents / Q000737:chemistry; D016503:Drug Delivery Systems; D004621:Embolization, Therapeutic / Q000295:instrumentation*; D020100:Hydrogels; D015394:Molecular Structure; D011142:Polyvinyl Alcohol / Q000737:chemistry*; D000644:Quaternary Ammonium Compounds
chemical_list: D004396:Coloring Agents; D020100:Hydrogels; D000644:Quaternary Ammonium Compounds; D011142:Polyvinyl Alcohol