Non-covalently surface modification of graphene oxide nanosheets and its role in the enhancement of the epoxy-based coatings` physical properties

Preparing high-performance microspheres based on the chitosan-assisted dispersion of reduced graphene oxide in aqueous solution for bilirubin removal

The removal of excess bilirubin from blood is of great clinical importance. Reduced graphene oxide (rGO) is often used to efficiently remove bilirubin. However, thin rGO pieces tend to aggregate in the aqueous phase because they are hydrophobic. In this context, we propose an effective strategy based on the chitosan-assisted (CS-assisted) dispersion of rGO to produce high-performance bilirubin-adsorbing microspheres. CS possesses a hydrophobic CH structure, which offers strong hydrophobic interactions with rGO that assist its dispersion, and the large number of hydrophilic sites of CS increases the hydrophilicity of rGO. CS serves as a dispersant in a surfactant-like manner to achieve a homogeneous and stable CS/rGO dispersion by simply and gently stirring CS and rGO in a LiOH/KOH/urea/H2O system. Subsequently, CS/rGO hybrid microspheres were prepared by emulsification. CS ensures blood compatibility as a base material, and the entrapped rGO contributes to mechanical strength and a high adsorption capacity. The CS/rGO microspheres exhibited a high bilirubin adsorption capacity (215.56 mg/g), which is significantly higher than those of the rGO and CS microspheres. The determined mass-transfer factors revealed that the rich pores of the CS/rGO microspheres promote mass transfer during bilirubin adsorption (equilibrium is almost achieved within 30 min). The CS/rGO microspheres are promising candidates for bilirubin removal owing to a combination of high strength, blood compatibility, and high adsorption capacity.

Synthesis of Mn-MOFs loaded zinc phosphate composite for water-based acrylic coatings with durable anticorrosion performance on mild steel

A new metal–organic framework (MOF) compound [Mn₂(2,2′-bca)₂(H₂O)₂]_n (Mn-MOFs) was successfully synthesized by solvothermal method, and Mn-MOFs@Zn material was prepared by loading zinc phosphate onto Mn-MOFs by ball milling, then Mn-MOFs@Zn was added to the water-based acrylic paint to prepare Mn-MOFs@Zn@acrylic coating. The AC impedance test results showed Mn-MOFs@Zn@acrylic coating has higher corrosion inhibition performance and stability to mild steel when compared with blank coating. The impedance modulus of the blank coating in the low frequency region decreased by 90%, and the R_ct showed a trend of first increasing and then decreasing over time, the maximum R_ct was only 303.8 Ω, which was only Mn-MOFs@Zn@acrylic coating one-seventh of the R_ct value. The artificial scratch experiment showed that the Mn-MOFs@Zn@acrylic coating only slightly corrodes at the scratches, because Mn-MOFs@Zn material made the coating a self-repairing function and improved the durable anticorrosion performance of the acrylic coating.

The above scheme shows the preparation route of Mn-MOFs@Zn@acrylic coating. Mn-MOFs@Zn and water-based acrylic varnish were evenly dispersed in water; then the coating was applied to the surface of mild steel and then scratched with a knife.

Recent Advances in Graphene Oxide-Based Anticorrosive Coatings: An Overview

The present review outlines the most recent advance in the field of anticorrosive coatings based on graphene oxide nanostructures as active filler. This carbonaceous material was extensively used in the last few years due to its remarkable assets and proved to have a significant contribution to composite materials. Concerning the graphene-based coatings, the synthesis methods, protective function, anticorrosion mechanism, feasible problems, and some methods to improve the overall properties were highlighted. Regarding the contribution of the nanostructure used to improve the capability of the material, several modification strategies for graphene oxide along with the synergistic effect exhibited when functionalized with other compounds were mainly discussed.

Application of ZnO/CNT@Fe3O4nanocomposite in amplifying the anti-leukemic effect of imatinib: a novel strategy to adjuvant therapy in chronic myeloid leukemia

The advent of tyrosine kinase inhibitors (TKI) in the therapeutic protocols of chronic myeloid leukemia (CML) sparked a flame of hope for patients to finally reach to the milestone of the complete remission. However, by the different mutations bypassing the effectiveness of Imatinib, a powerful impetus has emerged to bring more efficient agents into the field of treatment. The results of the present study declared that the companionship of our synthesized ZnO/CNT@Fe3O4 nanocomposite with Imatinib was able to more efficiently decrease the survival of CML-derived K562 cells probably through inducing reactive oxygen species (ROS)-dependent apoptosis. We also found a superior cytotoxicity in the presence of a well-known autophagy inhibitor, indicating that the apoptotic effect of this treatment was probably enhanced through the suppression of autophagy. Investigating the molecular mechanisms involved in the growth-suppressive effect of ZnO/CNT@Fe3O4-plus-Imatinib clarified that the up-regulation of SIRT1 ceased the progression of the cell cycle, foremost by increasing the expression of p21 and p27 cyclin-dependent kinase inhibitors. Notably, we reported for the first time that either direct or indirect suppression of c-Myc resulted in an enhanced anti-leukemic effect; suggesting that the overexpression of c-Myc could play a contributory role in attenuating the efficacy of ZnO/CNT@Fe3O4-plus-Imatinib in K562. Given to the established efficacy of ZnO/CNT@Fe3O4 in CML cells, our preclinical results suggest that the application of this nanocomposite is an appealing strategy to boost the anti-leukemic effect of TKIs, which should be further studied in combination with other anti-cancer agents either in hematologic malignancies or solid tumors.