3D-Printed Photocurable Resin with Synergistic Hydrogen Bonding Based on Deep Eutectic Solvent

Vat polymerization, one of the 3D printing technologies, has been widely applied owing to its advantageous properties, such as high accuracy and surface quality. However, the applicability of this technology is limited to end-use product manufacturing, requiring advancements due to a gradual increase in the performance requirements and functional demands of the products. In this study, deep eutectic solvent-based photocurable resins (PCRs) with synergistic hydrogen bonding are synthesized using a facile and ecofriendly procedure to tune monomer proportions. The as-prepared PCRs, with ultralow viscosity and ultrahigh curing rate, are compatible with commercial liquid-crystal display printers. The 3D-printed parts with high optical transparency, stiffness, and thermal resistance exhibit humidity-dependent electrical conductivity and mechanical properties. In addition, the 3D-printed objects demonstrate self-healing features due to the synergistic effect of high-density hydrogen bonding in the microphase-separated polymer matrix. Moreover, different categories of structural assembly, from 2D to 3D and small to large, are demonstrated, and their solubility ensued in recycling and remolding. The synthesized PCRs are suitable for fabricating sacrificial molds, enabling the on-demand fabrication of precise multifunctional structures with various materials, which are otherwise incompatible with UV-based 3D printing, facilitating 3D printing by overcoming its material-selection limitations

Overcoming Multidrug Resistance through the Synergistic Effects of Hierarchical pH-Sensitive, ROS-Generating Nanoreactors

Recently, multidrug resistance (MDR) has become a major clinical chemotherapeutic burden that robustly diminishes the intracellular drug levels through various mechanisms. To overcome the doxorubicin (Dox) resistance in tumor cells, we designed a hierarchical nanohybrid system possessing copper-substituted mesoporous silica nanoparticles (Cu-MSNs). Further, Dox was conjugated to copper metal in the Cu-MSNs framework through a pH-sensitive coordination link, which is acutely sensitive to the tumor acidic environment (pH 5.0–6.0). In the end, the nanocarrier was coated with D-α-Tocopherol polyethylene glycol 1000 succinate (TPGS), a P-gp inhibitor-entrenched compact liposome net for obstructing the drug efflux pump. Copper ions in the framework synergize the antitumor activity of Dox by enhancing the intracellular reactive oxygen species (ROS) levels through a Fenton-like reaction-mediated conversion of hydrogen peroxide. Furthermore, intracellularly generated ROS triggered the apoptosis by reducing the cellular as well as mitochondrial membrane integrity in MDR cells, which was confirmed by the mitochondrial membrane potential (MMP) measurement. The advancement of the design and critical improvement of cytotoxic properties through free radical attack demonstrate that the proposed hierarchical design can devastate the MDR for efficient cancer treatment