title: Reduction-sensitive amphiphilic triblock copolymers self-assemble into stimuli-responsive micelles for drug delivery.
abstract: Polymeric nanostructures obtained through self-assembly of reduction-sensitive amphiphilic triblock copolymers were investigated as potential drug delivery systems. The characteristic feature of these polymers is their cleavable disulfide bond in the center of the hydrophobic block. Therefore, the triblock copolymers can be cleaved into amphiphilic diblock copolymers. A poly(2-hydroxyethyl methacrylate)-b-poly(butyl methacrylate)-S-S-poly(butyl methacrylate)-b-poly(2-hydroxyethyl methacrylate) (PHEMA-b-(PBMA-S-S-PBMA)-b-PHEMA) triblock copolymer was synthesized. It self-assembled into micelles which were used to encapsulate hydrophobic dye molecules (Nile Red, BodiPy 630/650) as model payloads. The self-assembled nanostructures disintegrated upon reduction of the disulfide bond, releasing their cargo and yielding larger particles that formed aggregates in solution after 24 h. A burst release of payload was shown within the first 15 min, followed by a constant release over several hours. As concentration gradients of reducing agents are commonly found in biological systems, the micelles could be used as redox-sensitive nanocarriers for the intracellular delivery of drugs.
authors: Department of Chemistry, University of Basel, Klingelbergstrasse 80, 4056, Basel, Switzerland.
authors: Smahan
authors: S
authors: Toughraï
authors: Violeta
authors: V
authors: Malinova
authors: Raffaello
authors: R
authors: Masciadri
authors: Sindhu
authors: S
authors: Menon
authors: Pascal
authors: P
authors: Tanner
authors: Cornelia
authors: C
authors: Palivan
authors: Nico
authors: N
authors: Bruns
authors: Wolfgang
authors: W
authors: Meier
mesh_terms: D016503:Drug Delivery Systems; D006801:Humans; D057927:Hydrophobic and Hydrophilic Interactions; D008823:Micelles; D049329:Nanostructures / Q000737:chemistry; D011102:Polyhydroxyethyl Methacrylate / Q000138:chemical synthesis* / Q000737:chemistry; D011108:Polymers / Q000138:chemical synthesis* / Q000737:chemistry; D011109:Polymethacrylic Acids / Q000138:chemical synthesis* / Q000737:chemistry; D012996:Solutions / Q000737:chemistry
chemical_list: D008823:Micelles; D011108:Polymers; D011109:Polymethacrylic Acids; D012996:Solutions; D011102:Polyhydroxyethyl Methacrylate; C068872:polybutyl methacrylate
keywords: amphiphilic block copolymers; micelles; reduction-sensitive intracellular drug delivery systems; self-assembly