During the past decade, increasing attention has been paid to photoluminescent nanocarbon materials, namely, carbon quantum dots (CQDs). It is gradually accepted that surface engineering plays a key role in regulating the properties and hence the applications of the CQDs. In this paper, we prepared highly charged CQDs through a one-pot pyrolysis with citric acid as carbon source and a room-temperature imidazolium-based ionic liquid as capping agent. The as-prepared CQDs exhibit high quantum yields up to 25.1% and are stable under various environments. In addition, the amphiphilicity of the CQDs can be facilely tuned by anion exchange, which leads to a spontaneous phase transfer between water and oil phase. The promising applications of the CQDs as ion sensors and fluorescent inks have been demonstrated. In both cases, these ionic-liquid-modified CQDs were found to possess novel characteristics and/or superior functions compared to existing ones.

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Mixtures of cationic and anionic (catanionic) single-chain surfactants can readily form bilayers in aqueous solutions, [1] in which uni-and multilamellar onion phases (the so-called vesicle phase) are often observed to be in equilibrium. [2] Since vesicles represent simple model systems for biological membranes and have practical applications (for example, for controlled drug or DNA release), [3] investigations of vesicle phases are of considerable interest in different areas, including surfactants, materials, and life sciences. Recently, two new self-assembled structures of controlled size (nanodisks and regular hollow icosahedra) were observed in dilute catanionic surfactants with H + and OH À counterions by Zemb and coworkers. [4][5][6] Such so-called "true" catanionic systems, with a nonswelling but finite uptake of water, and with a spacing of the same order as described in the current study were studied and documented by Jokela et al. [7] It was also later established by Rand, Parsegian, and Leiken [8] that the lamellar phase at maximum swelling of salt-free catanionic systems with a zero osmotic pressure, that is, the repulsive hydration interaction is compensated by van der Waals force at that point. The molar ratio r of the anionic to cationic components controls the structural surface charge and, hence, controls the long-range repulsive interaction independently of the weight volume fraction (f), which in turn controls the average colloidcolloid distance. The salt-free catanionic systems can be represented in a ternary phase diagram whose two independent variables are f and r.[6]Herein we report, for the first time to our knowledge, the discovery of a "true", salt-free concentrated catanionic uniand multilamellar onion phase that differs from the catanionic surfactant systems with excess salt that are formed by the combination of the counterions, as evident from our freezefracture transmission electron microscopy (FF-TEM) observations and small-angle X-ray scattering (SAXS) measurements. This molecular catanionic couple comprises the longest hydrocarbon chains described to date, so it was essential to determine if the carbon chains were in a frozen (gel) or liquid state. The size of the unilamellar vesicles ranges from about 20 to 700 nm and that of the large onions are several micrometers. The interlamellar spacing between the bilayers of onions is about 35 nm, thus suggesting rather compact packing of the bilayers. The high osmotic pressure sustains the highly stable colloidal suspension of the catanionic onion phase. The observations of the onion phase may prove valuable and stimulating to fellow specialists, not least as "true" catanionic surfactant systems do not seem to be exhaustively investigated yet.The "true" salt-free catanionic vesicle phase was obtained by mixing aqueous solutions of trimethyltetradecylammonium hydroxide (TTAOH) and oleic acid (OA; see Figure 3). The stock solution of TTAOH (pH 12-13) was prepared from the commercial bromide form (TTABr) by anion exchange with a strong b...

The antitumor immune response involves a cascade of three phases, namely, antigen presentation (Phase I), lymphocyte activation and proliferation/differentiation (Phase II), and tumor elimination (Phase III). Therefore, an ideal immunotherapy nanoplatform is one that can simultaneously execute these three phases. However, it is of great challenge to develop a single immunotherapy nanoplatform which can deliver individual immunoagent to their ondemand target sites for simultaneously tailoring three phases because of the different target sites restricted by three phases. Herein, for the first time we reported a three-in-one immunotherapy nanoplatform that can simultaneously execute these three phases. Chlorin e6 (Ce6)-conjugated hyaluronic acid (HC), dextro-1-methyl tryptophan (1-mt)-conjugated polylysine (PM) and anti-PD-L1 monoclonal antibodies (aPD-L1) were rationally designed as aPD-L1@HC/PM NPs via an assembling strategy. The step-by-step detachment of the antigen from near-infrared light irradiated HC component, the indoleamine-pyrrole 2,3-dioxygenase (IDO) pathway inhibitor 1-mt, and the anti-PD-L1 toward their on-demand target sites demonstrated the simultaneous tailoring of Phase I, Phase II, and Phase III, respectively, of the immunotherapy. The aPD-L1@ HC/PM NPs were verified to be an excellent immunotherapy nanoplatform against tumor metastasis, relapse, and postsurgical regrowth because of the cascade-amplifying cancer-immunity cycle. The present all-immunity-phase-boosted immunotherapy strategy is of great interest for designing excellent immunotherapy treatments.

Self-assembled vesicles, structurally equivalent to some hydrotropes, have been obtained from a Zn2+-fluorous surfactant or in the mixture of Zn2+-fluorous surfactant/zwitterionic surfactant in room-temperature ionic liquids (RTILs). The existence of bilayers arranged in vesicles in RTILs would be very exciting, open several new possibilities as reaction media, and increase our understanding of the physical and chemical factors for self-assembling systems in RTILs.

Here, we prepared novel redox-sensitive drug delivery system based on copolymer-drug conjugates methoxy poly(ethylene glycol)-poly(γ-benzyl l-glutamate)-disulfide-docetaxel (mPEG-PBLG-SS-DTX) to realize the desirable cancer therapy. First, copolymers of methoxy poly(ethylene glycol)-poly(γ-benzyl l-glutamate) (mPEG-PBLGs) with different molecular weight (mPEG2000-PBLG1750 and mPEG5000-PBLG1750) were synthesized via the ring open polymerization (ROP) of 5-benzyl-l-glutamate-N-carboxyanhydride (γ-Bzl-l-Glu-NCA) initiated by monoamino-terminated mPEG (mPEG-NH2). Then, the docetaxel (DTX) was conjugated to the block polymers through a linkage containing disulfide bond to obtain mPEG-PBLG-SS-DTXs, including mPEG2000-PBLG1750-SS-DTX and mPEG5000-PBLG1750-SS-DTX. The obtained copolymer-drug conjugates mPEG2000-PBLG1750-SS-DTX and mPEG5000-PBLG1750-SS-DTX could self-assemble into nanosized micelles in aqueous environment via dialysis method with a low critical micelle concentration (CMC, 3.98 and 6.94 μg/mL, respectively). The size of the micelles was approximately 101.3 and 148.9 nm, respectively, with a narrow size distribution. They released approximately 40% DTX in a sustained way in the presence of 50 mM DTT after 120 h in comparison with only approximately 10% DTX released from micelles in the absence of DTT. The high cytotoxicity was identified for mPEG-PBLG-SS-DTXs micelles against MCF-7/ADR and A549 cells, and the IC50 of mPEG-PBLG-SS-DTXs micelles against MCF-7/ADR for 24 h was roughly a 15th of the value of free DTX. Moreover, the mPEG-PBLG-SS-DTXs micelles could be efficiently uptaken by MCF-7/ADR and A549 cells. Thus, the present constructed mPEG-PBLG-SS-DTXs micelles were very promising for effective cancer therapy.

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Two routes to vesicle formation were designed to prepare uni- and multilamellar vesicles in salt-free aqueous solutions of surfactants. The formation of a surfactant complex between a double-chain anionic surfactant with a divalent-metal ion as the counterion and a single-chain zwitterionic surfactant with the polar group of amine-oxide group is described for the first time as a powerful driving force for vesicle-phases constructed from salt-free mixtures of aqueous surfactant solutions. As a typical example, a Zn(2+)-induced charged complex fluid, vesicle-phase has been studied in aqueous mixtures of tetradecyldimethylamine oxide (C(14)DMAO) and zinc 2,2-dihydroperfluorooctanoate [Zn(OOCCH(2)C(6)F(13))(2)]. This ionically charged vesicle-phase formed due to surfactant complexation has interesting rheological properties and is not shielded by excess salts because there are no counterions in the solution. Such a vesicle-phase of surfactant complex is important for many applications; for example, the vesicle-phase was further used to produce in situ the vesicle-phase of the salt-free cationic/anionic (catanionic) surfactants, C(14)DMAOH(+)-(-)OOCCH(2)C(6)F(13). The salt-free catanionic vesicle-phase could be produced through injecting H(2)S gas into the C(14)DMAO/Zn(OOCCH(2)C(6)F(13))(2) vesicle-phase, because the zwitterionic surfactant C(14)DMAO can be charged by the H(+) released from H(2)S to become a cationic surfactant and Zn(2+) was precipitated as ZnS. After the ZnS precipitates were removed from C(14)DMAO/Zn(OOCCH(2)C(6)F(13))(2) solutions, the final mixed solution does not contain excess salts as do other cationic/anionic surfactant systems. Both the C(14)DMAO-Zn(OOCCH(2)C(6)F(13))(2) complex and the resulting catanionic C(14)DMAOH(+)-(-)OOCCH(2)C(6)F(13) solution are birefringent Lalpha-phase solutions that consist of uni- and multilamellar vesicles. Ring-shaped semiconductor ZnS materials with encapsulated ZnS precipitates and regular spherical ZnS particles were prepared, which resulted in a transition from vesicles composed of metal-ligand complexes to vesicles held together by ionic interactions in the salt-free aqueous systems. This strategy should provide a new method to prepare inorganic materials. The present routes to form vesicles solve a problem: how to prepare nanomaterials using surfactant self-assembly, with structure controlled not by the growing material, but by the phase behavior of the surfactants.