No abstract

Objective: Exosomes (Exos) are membrane-encased vesicles derived by nearly all cell types for intercellular communication and regulation. They also received attention for their use as natural therapeutic platforms and drug delivery system. Classically activated M1 macrophages suppress tumor growth by releasing pro-inflammatory factors. This study investigated the suitability of M1-exosomes (M1-Exos) as drug carrier and their effect on the NF-κB signal pathway and further detected whether macrophages repolarization can potentiate the antitumor activities of chemotherapeutics. Methods: M1-Exos were isolated from M1-macrophages by ultracentrifugation and characterized by transmission electron, nanoparticle tracking analysis, dynamic light scattering and western blot. Then M1-Exos were used as Paclitaxel (PTX) carriers to prepare a nano-formulation (PTX- M1-Exos). A relatively simple slight sonication method was used to prepare the drug delivery system (PTX-M1-Exos). The cytotoxicity of PTX-M1-Exos on cancer cells was detected by MTT and flow cytometry in vitr o. 4T1 tumor bearing mice were used to perform the therapeutic effect of PTX-M1-Exos in vivo . Results: The expression of caspase-3 in breast cancer cells was increased when co-incubated with macrophages in the presence of M1-Exos in vitro . The production of pro-inflammatory cytokines was increased after exposure of macrophages in M1-Exos. M1-Exos provided a pro-inflammatory environment which enhanced the anti-tumor activity via caspase-3 mediated pathway. The treatment of M1-Exos to the tumor bearing mice exhibit anti-tumor effects in vivo . Meanwhile, the treatment of PTX-M1-Exos demonstrated higher anti-tumor effects than the M1-Exos or PTX group. Conclusion: The results in our study indicate that the M1-Exos act as the carrier to deliver PTX into the tumor tissues, and also enhance the anti-tumor effects of chemotherapeutics in tumor bearing mice.

No abstract

Self-assembled binary nanocrystal superlattices (BNSLs) represent an important class of solid-state materials with potentially designed properties. In pursuit of widening the range of applications for binary superlattice materials, it is desirable to develop scalable assembly methods that enable high-quality BNSLs with tailored compositions, structures, and morphologies. Here, we report the gram-scale assembly of crystalline binary nanocrystal superparticles with high phase purity through an emulsion-based process. The structure of the resulting BNSL colloids can be tuned in a wide range (AB 13 , AlB 2 , MgZn 2 , NaCl, and CaCu 5 ) by varying the size and/or number ratios of the two nanocrystal components. Access to large-scale, phase-pure BNSL colloids offers vast opportunities for investigating their physiochemical properties, as exemplified by AB 13 -type CoFe 2 O 4 −Fe 3 O 4 binary superparticles. Our results show that CoFe 2 O 4 −Fe 3 O 4 binary superparticles not only display enhanced magnetic coupling but also exhibit superior lithium-storage properties. The nonclosed-packed NC packing arrangements of AB 13 -type binary superparticles are found to play a key role in facilitating lithiation/delithiation kinetics and maintaining structural integrity during repeated cycling. Our work establishes the scalable assembly of high-quality BNSL colloids, which is beneficial for accelerating the exploration of multicomponent nanocrystal superlattices toward various applications.

The successful formulation of itraconazole and odanacatib into nanoparticle form with diameters of 145 and 350 nm, respectively, using rapid, block copolymer-directed precipitation is presented. These are the smallest stable nanoparticles that have been reported for these compounds. The difference in size of the nanoparticles for the two compounds is explained by the difference in nucleation rate and its dependence on supersaturation. The conditions for stability after formation are presented: storage at 5 degrees C and removal of residual processing solvent. These requirements are explained in terms of solute solubility and its dependence on both temperature and solvent concentration. The theory of Ostwald ripening provides the framework for understanding the differences in stability observed for the two compounds. The dynamics of the hydrophobic polymer block plays a major role in long-term stability as demonstrated by the behavior of nanoparticles stabilized by poloxamer vs polystyrene-b-polyethylene oxide polymers.