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The formation mechanisms of porous particles from self-assembly of amphiphilic diblock copolymers inside an oil-in-water emulsion droplet upon evaporation of the organic solvent are investigated based on Monte Carlo simulations for the first time. A morphological diagram of particles is constructed as a function of the surfactant concentration (φ) and the copolymer composition characterized by the volume fraction of the hydrophilic B block ( f

Based on studies combining experiments and simulations, internally ordered colloidal particles that are able to undergo morphological transformations both in shape and internal structure are presented. The particles are prepared by emulsion solvent evaporation-induced 3D soft confined assembly of di-block copolymer polystyrene-block-poly(4-vinylpyridine) (PS-b-P4VP). Control over the solvent selectivity leads to a dramatic change in shape and internal structure for particles. Pupa-like particles of lamellar morphology are obtained when using a non-selective solvent, while patchy particles possessing a plum pudding structure formed when the solvent is selective for PS-block. More interestingly, 3D soft confined annealing drives order-order morphological transformation of the particles. The morphology of reshaped particles can be well controlled by varying the solvent selectivity, annealing time, and interfacial interaction. The experimental results can be explained based on simulations. This study can offer considerable scope for the design of new stimuli-responsive colloidal particles for potential applications in photonic crystal, drug delivery and release, sensor and smart coating, etc.

Optimal strategy for the management of high on-treatment platelet reactivity (HPR), an independent predictor of ischaemic events, is not yet clear. The aim of this study was to explore the safety and efficacy of personalized antiplatelet therapy based on platelet function testing in patients with HPR. A total of 840 patients with HPR who underwent coronary stenting for acute coronary syndrome (ACS) were randomly assigned in a 1:2 ratio to receive standard dual-antiplatelet therapy ( n = 280) or platelet function-guided optimal-antiplatelet therapy ( n = 560). In the optimal group, patients initially received clopidogrel 150 mg/day on top of aspirin and switched to triple antiplatelet therapy with additional cilostazol if repeat platelet function assay after 3 days indicated a sustained HPR. The primary endpoint was the composite of all-cause death, myocardial infarction, clinically driven target vessel revascularization (TVR), or stroke. Optimal therapy resulted in significantly lower 30-day HPR rate (30.1 vs. 44.3%, P < 0.001). At 1-year follow up, optimal therapy was associated with significantly lower incidence of primary endpoint events (2.7 vs. 6.8%, P = 0.006) compared with standard therapy, mainly due to the reduction of TVR. These beneficial effects were sustained at 2 years (4.5 vs. 9.2%, P = 0.006), with similar bleeding event rates between groups (7.3 vs. 6.5%, P = 0.565). Optimal-antiplatelet therapy based on platelet function testing is effective in attenuating HPR and improving long-term outcomes for ACS patients with no increase in bleeding events.

The phase behavior of symmetric ABC triple-hydrophilic triblock copolymers in concentrated aqueous solutions is investigated using a simulated annealing technique. Two typical cases, in which the hydrophilicity of the middle B-block is either stronger or weaker than that of the end A- and C-blocks, are studied. In these two cases, a variety of phase diagrams are constructed as a function of the volume fraction of the B-block and the copolymer concentration ([Formula: see text] for both non-frustrated and frustrated copolymers. Structures, such as two-color alternatingly packed cylinders or gyroid, and lamellae-in-lamellae etc. that do not occur in the melt system, are obtained in solutions. Rich phase transition sequences, especially re-entrant phase transitions involving complex continuous networks of alternating gyroid and alternating diamond are observed for a given copolymer with decreasing [Formula: see text] . The difference in hydrophilicity among different blocks can result in inhomogeneous distribution of solvent molecules in the morphology, and with the decrease of [Formula: see text] , the distribution of solvent molecules presents a non-monotonic variation. This results in a non-monotonic variation of the effective volume fraction of each domain with the decrease of [Formula: see text] , which induces the re-entrant phase transitions. The presence of a good solvent for all the blocks can cause changes in the effective segregation strengths between different blocks and also in chain conformations, hence can alter the bulk phases and results in the occurrence of new structures and phase transitions. Especially, structures having A-C interfaces or A-C mixed domains can be obtained even in the non-frustrated copolymer systems, and structures obtained in the frustrated systems may be similar to those obtained in the non-frustrated systems. The window of the alternating gyroid structures may occupy a large part of the phase diagram for non-frustrated copolymers with stronger B-hydrophilicity. This behavior can be used to tune the self-assembled structures of block copolymers.