title: Small angle neutron scattering investigations (SANS) of polyelectrolyte multilayer capsules templated on human red blood cells.
abstract: Polyelectrolyte capsules were fabricated by layer-by-layer deposition of poly(styrene sulfonate) (PSS) and poly(allylamine hydrochloride) (PAH) on glutardialdehyde fixed human erythrocytes and subsequent core dissolution using NaOCl as an oxidizing agent. SANS together with confocal laser scanning microscopy (CLSM) were applied to study capsule topology and interior as well as the layer thickness as a function of the deposition protocol, layer number, ionic concentration, and temperature treatment. The capsules contained various amounts of trapped polyelectrolyte. Retention depended on the order of polyelectrolyte deposition and layer number, which influenced layer permeability. The capsule wall thickness was found to be much smaller (3-4.5 nm in total) than what was known for polyelectrolyte multilayer walls, where every single layer contributes about 1.8 nm to the total thickness. NaCl (0.1 mM) caused a layer thickness decrease by 16%. Annealing at 70 degrees C induced capsule shrinking together with an increase of the wall thickness by 85% and wall density by 12%.
authors.affiliation: Institute of Medical Physics and Biophysics, Leipzig University, D-04103 Leipzig, Germany. irina.estrela-lopis@medizin.uni-leipzig.de
authors.forename: Irina
authors.initials: I
authors.lastname: Estrela-Lopis
authors.forename: Stefano
authors.initials: S
authors.lastname: Leporatti
authors.forename: Elke
authors.initials: E
authors.lastname: Typlt
authors.forename: Daniel
authors.initials: D
authors.lastname: Clemens
authors.forename: Edwin
authors.initials: E
authors.lastname: Donath
mesh_terms: D002214:Capsules; D004912:Erythrocytes / Q000737:chemistry* / Q000166:cytology; D006801:Humans; D018613:Microscopy, Confocal; D009502:Neutrons; D011073:Polyamines / Q000737:chemistry*; D011137:Polystyrenes / Q000737:chemistry*; D012542:Scattering, Radiation
chemical_list: D002214:Capsules; D011073:Polyamines; D011137:Polystyrenes; C063994:polyallylamine; C003321:polystyrene sulfonic acid