title: Aggregation behavior of amphiphilic p(HPMA)-co-p(LMA) copolymers studied by FCS and EPR spectroscopy.
abstract: A combined study of fluorescence correlation spectroscopy and electron paramagnetic resonance spectroscopy gave a unique picture of p(HPMA)-co-p(LMA) copolymers in aqueous solutions, ranging from the size of micelles and aggregates to the composition of the interior of these self-assembled systems. P(HPMA)-co-p(LMA) copolymers have shown high potential as brain drug delivery systems, and a detailed study of their physicochemical properties can help to elucidate their mechanism of action. Applying two complementary techniques, we found that the self-assembly behavior as well as the strength of hydrophobic attraction of the amphiphilic copolymers can be tuned by the hydrophobic LMA content or the presence of hydrophobic molecules or domains. Studies on the dependence of the hydrophobic lauryl side chain content on the aggregation behavior revealed that above 5 mol % laury side-chain copolymers self-assemble into intrachain micelles and larger aggregates. Above this critical alkyl chain content, p(HPMA)-co-p(LMA) copolymers can solubilize the model drug domperidone and exhibit the tendency to interact with model cell membranes.
authors.affiliation: Institute of Organic Chemistry, Johannes Gutenberg University Mainz, Duesbergweg 10-14, 55099 Mainz, Germany.
authors.forename: Mirjam
authors.initials: M
authors.lastname: Hemmelmann
authors.forename: Dennis
authors.initials: D
authors.lastname: Kurzbach
authors.forename: Kaloian
authors.initials: K
authors.lastname: Koynov
authors.forename: Dariush
authors.initials: D
authors.lastname: Hinderberger
authors.forename: Rudolf
authors.initials: R
authors.lastname: Zentel
mesh_terms: D004294:Domperidone / Q000737:chemistry; D016503:Drug Delivery Systems; D004578:Electron Spin Resonance Spectroscopy / Q000379:methods*; D057927:Hydrophobic and Hydrophilic Interactions; D008081:Liposomes / Q000737:chemistry; D008689:Methacrylates / Q000138:chemical synthesis*; D008823:Micelles; D008954:Models, Biological; D011108:Polymers / Q000138:chemical synthesis*; D013050:Spectrometry, Fluorescence / Q000379:methods*; D013501:Surface-Active Agents / Q000737:chemistry; D005464:Fluorobenzenes; D005466:Fluorocarbons
chemical_list: D004294:Domperidone; D008081:Liposomes; D008689:Methacrylates; D008823:Micelles; D011108:Polymers; D013501:Surface-Active Agents; C035583:pentafluorophenylmethacrylate; D005464:Fluorobenzenes; D005466:Fluorocarbons; C032802:hydroxypropyl methacrylate