Additional file 1 of EphA2-specific microvesicles derived from tumor cells facilitate the targeted delivery of chemotherapeutic drugs for osteosarcoma therapy

Additional file 1: Fig. S1. The distributions of 0.1, 0.8 and 3 μm latex beads, PBS, mixed latex beads, mixture of 3 μm latex beads and MVs were analyzed by flow cytometry

Fast Contact of Solid–Liquid Interface Created High Strength Multi-Layered Cellulose Hydrogels with Controllable Size

Novel onion-like and multi-layered tubular cellulose hydrogels were constructed, for the first time, from the cellulose solution in a 7% NaOH/12% urea aqueous solvent by changing the shape of the gel cores. In our findings, the contacting of the cellulose solution with the surface of the agarose gel rod or sphere loaded with acetic acid led to the close chain packing to form immediately a gel layer, as a result of the destruction of the cellulose inclusion complex by acid through inducing the cellulose self-aggregation. Subsequently, multi-layered cellulose hydrogels were fabricated via a multi-step interrupted gelation process. The size, layer thickness and inter-layer space of the multi-layered hydrogels could be controlled by adjusting the cellulose concentrations, the gel core diameter and the contacting time of the solid–liquid interface. The multi-layered cellulose hydrogels displayed good architectural stability and solvent resistance. Moreover, the hydrogels exhibited high compressive strength and excellent biocompatibility. L929 cells could adhere and proliferate on the surface of the layers and in interior space, showing great potential as tissue engineering scaffolds and cell culture carrier. This work opens up a new avenue for the construction of the high strength multi-layered cellulose hydrogels formed from inner to outside via a fast contact of solid–liquid interface

Hair-Inspired Crystal Growth of HOA in Cavities of Cellulose Matrix via Hydrophobic–Hydrophilic Interface Interaction

As one of the most ordinary phenomena in nature, numerous pores on animal skins induce the growth of abundant hairs. In this study, cavities of a cellulose matrix were used as hard templates to lead the hair-inspired crystal growth of 12-hydroxyoctadecanoic acid (HOA) through hydrophobic–hydrophilic interface interaction, and short hair-like HOA crystals with a smooth surface were formed on cellulose films. In our findings, by using solvent evaporation induced crystallization, hydrophobic HOA grew along the hydrophilic cellulose pore wall to form regular vertical worm-like and pillar-like crystals with an average diameter of about 200 nm, depending on the experimental conditions and HOA concentration. The formation mechanism of the short hair-like HOA crystals as well as the structure and properties of the cellulose/HOA submicrometer composite films were studied. The pores of the cellulose matrix supplied not only cavities for the HOA crystals fixation but also hydrophilic shells to favor the vertical growth of the relatively hydrophobic HOA crystals. The cellulose/HOA submicrometer composite films exhibited high hydrophobicity, as a result of the formation of the solid/air composite surface. Furthermore, 4-(1,2,2-triphenylethenyl) benzoic acid, an aggregation-induced emission luminogen, was used to aggregate on the cellulose surface with HOA to emit and monitor the HOA crystal growth, showing bifunctional photoluminscence and self-cleaning properties. This work opens up a novel one-step pathway to design bio-inspired submicrometer materials by utilizing natural products, showing potential applications in self-cleaning optical devices

Hair-Inspired Crystal Growth of HOA in Cavities of Cellulose Matrix via Hydrophobic–Hydrophilic Interface Interaction

As one of the most ordinary phenomena in nature, numerous pores on animal skins induce the growth of abundant hairs. In this study, cavities of a cellulose matrix were used as hard templates to lead the hair-inspired crystal growth of 12-hydroxyoctadecanoic acid (HOA) through hydrophobic–hydrophilic interface interaction, and short hair-like HOA crystals with a smooth surface were formed on cellulose films. In our findings, by using solvent evaporation induced crystallization, hydrophobic HOA grew along the hydrophilic cellulose pore wall to form regular vertical worm-like and pillar-like crystals with an average diameter of about 200 nm, depending on the experimental conditions and HOA concentration. The formation mechanism of the short hair-like HOA crystals as well as the structure and properties of the cellulose/HOA submicrometer composite films were studied. The pores of the cellulose matrix supplied not only cavities for the HOA crystals fixation but also hydrophilic shells to favor the vertical growth of the relatively hydrophobic HOA crystals. The cellulose/HOA submicrometer composite films exhibited high hydrophobicity, as a result of the formation of the solid/air composite surface. Furthermore, 4-(1,2,2-triphenylethenyl) benzoic acid, an aggregation-induced emission luminogen, was used to aggregate on the cellulose surface with HOA to emit and monitor the HOA crystal growth, showing bifunctional photoluminscence and self-cleaning properties. This work opens up a novel one-step pathway to design bio-inspired submicrometer materials by utilizing natural products, showing potential applications in self-cleaning optical devices

Construction of Chitin/PVA Composite Hydrogels with Jellyfish Gel-Like Structure and Their Biocompatibility

High strength chitin/poly­(vinyl alcohol) (PVA) composite hydrogels (RCP) were constructed by adding PVA into chitin dissolved in a NaOH/urea aqueous solution, and then by cross-linking with epichlorohydrin (ECH) and freezing–thawing process. The RCP hydrogels were characterized by field emission scanning electron microscopy, FTIR, differential scanning calorimetry, solid-state ¹³C NMR, wide-angle X-ray diffraction, and compressive test. The results revealed that the repeated freezing/thawing cycles induced the bicrosslinked networks consisted of chitin and PVA crystals in the composite gels. Interestingly, a jellyfish gel-like structure occurred in the RCP75 gel with 25 wt % PVA content in which the amorphous and crystalline PVA were immobilized tightly in the chitin matrix through hydrogen bonding interaction. The freezing/thawing cycles played an important role in the formation of the layered porous PVA networks and the tight combining of PVA with the pore wall of chitin. The mechanical properties of RCP75 were much higher than the other RCP gels, and the compressive strength was 20× higher than that of pure chitin gels, as a result of broadly dispersing stress caused by the orderly multilayered networks. Furthermore, the cell culture tests indicated that the chitin/PVA composite hydrogels exhibited excellent biocompatibility and safety, showing potential applications in the field of tissue engineering