Tuning amphiphilicity/temperature‐induced self‐assembly and in‐situ disulfide crosslinking of reduction‐responsive block copolymers

Abstract

New poly(ethylene oxide)-based block copolymers (ssBCs) with a random copolymer block consisting of a reduction-responsive disulfide-labeled methacrylate (HMssEt) and a thermoresponsive di(ethylene glycol)-containing methacrylate (MEO 2 MA) units were synthesized. The ratio of HMssEt/ MEO 2 MA units in the random P(MEO 2 MA-co-HMssEt) copolymer block enables the characteristics of well-defined ssBCs to be amphiphilic or thermoresponsive and double hydrophilic. Their amphiphilicity or temperature-induced self-assembly results in nanoaggregates with hydrophobic cores having different densities of pendant disulfide linkages. The effect of disulfide crosslinking density on morphological variation of disulfide-crosslinked nanogels is investigated. In response to reductive reactions, the partial cleavage of pendant disulfide linkages in the hydrophobic cores converts the physically associated aggregates to disulfide-crosslinked nanogels. The occurrence of in-situ disulfide crosslinks provides colloidal stability upon dilution.

Enhanced encapsulation of superparamagnetic Fe3O4 in acidic core-containing micelles for magnetic resonance imaging

“…S3 †). As reported, 46 such red-shi is attributed to increasing hydrophilicity of P(tBMA-co-MAA) cores in BCP-HY-45 micelles, compared to PtBMA cores in BCP-HY-0 micelles.…”

Redox-triggered crosslinking of a degradable polymer

“…Beyond providing access to cross-linked poly(lactic acid), this report demonstrates how the exquisite chemoselectivity of the Fe(II) and Fe(III) oxidation states of the catalyst can be used to control the onset of polymer crosslinking. Outside of redoxtriggered crosslinking reactions involving disulfide bridges, 44 the crosslinking reactions reported here are the first examples where crosslinking reactions can be controlled by redox reactions; they are the first that involve the use of a ring opening Fig. 3 T g ( ) and swellability ( ) of polymers obtained from redox-triggered crosslinking reactions at various [6] : lactide feed compositions.…”

Synthesis strategies for disulfide bond-containing polymer-based drug delivery system for reduction-responsive controlled release

“…Furthermore, it was claimed that the dual-bioresponsive nanogel functionalized with quaternary ammonium salt could efficiently accelerate cellular internalization. Chan et al described the reductionresponsive nanogel which was prepared by tuning amphiphilicity/temperature-induced self-assembly of the copolymers and then self-crosslinked by disulfide bonds [64]. The copolymer consisted of a reduction-responsive disulfide-labeled methacrylate (HMssEt) and a thermoresponsive di(ethylene glycol)-containing methacrylate (MEO 2 MA) units.…”