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Plasmonic vesicles combine the advantages of polymersomes and physiochemical properties of inorganic nanoparticles, exhibiting promising applications in theranostic nanovectors. However, although many of these plasmonic vesicles have been engineered as photothermal therapy (PTT) agents and drug carriers, they undergo structural destruction due to localized surface plasmon resonance (LSPR) effect. Notably, the disassembly of plasmonic vesicles leads to the burst release of encapsulated payloads and drastically decrease therapeutic efficacy. Herein, we report the fabrication of plasmonic vesicles that can be tracelessly cross-linked under 410 nm blue light irradiation, which can effectively avoid being disassembled when localized heat generation under light irradiation (e.g., 560 nm). Amphiphilic hybrid gold nanoparticles (AuNPs) functionalized with hydrophilic poly(ethylene oxide) (PEO) and hydrophobic poly(2-((((2-nitrobenzyl)oxy)carbonyl)amino)ethyl methacrylate) (PNBOC) blocks were synthesized via ligan...

Supramolecular vesicles, also referred to as polymersomes, self-assembled from amphiphilic polymers capable of synchronically loading with both hydrophilic and hydrophobic payloads have shown promising potential in drug delivery application. Herein, we report the fabrication of pH-responsive polymersomes via supramolecular self-assembly of amphiphilic diblock copolymers, poly(ethylene oxide)-b-poly(2-((((5-methyl-2-(2,4,6-trimethoxyphenyl)-1,3-dioxan-5-yl)methoxy)carbonyl)amino)ethyl methacrylate) (PEO-b-PTTAMA), which were synthesized via reversible addition–fragmentation chain transfer (RAFT) polymerization of a pH-responsive monomer (i.e., TTAMA) using a PEO-based macroRAFT agent. The resultant amphiphilic diblock copolymer then self-assembled into vesicles consisting of hydrophilic PEO coronas and pH-responsive hydrophobic bilayers, as confirmed by TEM and DLS measurements. The polymersomes containing cyclic benzylidene acetals in the hydrophobic bilayers were relatively stable under neutral pH, where...

Nonviral gene delivery vectors need to overcome both extracellular and intracellular obstacles before releasing plasmid DNA in the transcriptionally active form. However, serum and transport stability desired for cationic polymer/pDNA polyplexes contradicts with the eventual plasmid release requirement; chain lengths of cationic polymer vectors render additional compromise between cytotoxicity and transfection efficiency. Although the introduction of stimuli-triggered degradable cationic polymers can partially solve these issues, the quest for novel design criteria and elucidation of elementary cellular transport pathways are highly desirable. Herein we report a supramolecular approach to construct fluorogenic gene delivery vectors via self-assembly of intracellular milieu-reactive cationic amphiphiles. This new type of micellar nanocarriers can effectively bind pDNA to form polyplexes due to multivalent cationic segments at micellar coronas. Upon cellular uptake and endosomal escape, hydrophobic micellar...

Supramolecular aggregates of stimuli-responsive block copolymers are increasingly utilized as drug nanocarriers. Although in situ tracking their triggered disintegration and drug release processes at the cellular level is highly desirable, it remains a considerable challenge. We report the fabrication of double hydrophilic block copolymers covalently conjugated with α,β-unsaturated ketone-caged coumarin functionalities in the thermoresponsive block. Upon thermo-induced micellization and cellular uptake, Michael addition reaction of unsaturated ketone moieties with thiol compounds (GSH and Cys) in the reductive subcellular compartments leads to micelle-to-unimer transition. This is accompanied by concomitant fluorescence emission turn-on and triggered drug release, allowing for the process visualization.

We report on the fabrication of dynamic covalent shell cross-linked (SCL) micelles with hydrophobic cores conjugated with photocaged chemotherapeutic drugs and coronas functionalized with ligands for tumor cell targeting. Two types of amphiphilic diblock copolymers, P(CL-g-CPT)-b-P(OEGMA-co-MAEBA)-CPT and PCL-b-P(OEGMA-co-MAEBA-co-FA), were synthesized via the combination of ring-opening copolymerization (ROP) of e-caprolactone (CL) and 2-bromo-e-caprolactone (CL-Br), atom transfer radical polymerization (ATRP) of oligo(ethylene glycol) monomethyl ether methacrylate (OEGMA) and p-(methacryloxyethoxy) benzaldehyde (MAEBA) comonomers, and “click” post-functionalization with photocaged camptothecin (CPT) prodrug and alkynyl-functionalized folic acid (FA) moieties, respectively. Mixed micelles coassembled from PCL-b-P(OEGMA-co-MAEBA-co-FA) and P(CL-g-CPT)-b-P(OEGMA-co-MAEBA)-CPT possess hydrophobic cores conjugated with photocaged CPT prodrugs and hydrophilic outer coronas covalently attached with aldehyde gr...

We report on the fabrication of a novel type of ratiometric fluorescent polymeric probes for fluoride ions (F–) based on self-assembled micellar nanoparticles of P(MMA-co-NBDAE)-b-PF-b-P(MMA-co-NBDAE) coil–rod–coil triblock copolymer, where MMA, NBDAE, and PF are methyl methacrylate, 4-(2-acryloyloxyethylamino)-7-nitro-2,1,3-benzoxadiazole, and polyfluorene, respectively. Blue-emitting conjugated PF block and green-emitting NBDAE moieties with F– turn-off characteristics within the PMMA block serve as fluorescence resonance energy transfer (FRET) donors and switchable acceptors, respectively. For coil–rod–coil triblock copolymer in a good solvent such as THF, the blue emission of PF block dominates due to unimolecularly dissolved state associated with ineffective FRET process. The addition of F– ions only leads to ∼2.92-fold decrease of fluorescence intensity ratio, I515/I417, of characteristic NBDAE and PF emission bands. In acetone, the triblock copolymer spontaneously self-assembles into micelles posse...