Background: In order to obtain biomaterials with controllable physicochemical properties, hybrid biomaterials composed of biocompatible biopolymers and ceramic nanoparticles have attracted interests. In this study, we prepared biopolymer/ceramic hybrids consisting of various natural biopolymers and layered double hydroxide (LDH) ceramic nanoparticles via an electrophoretic method. We studied the structures and controlled-release properties of these materials. Results and discussion: X-ray diffraction (XRD) patterns and X-ray absorption spectra (XAS) showed that LDH nanoparticles were formed in a biopolymer hydrogel through electrophoretic reaction. Scanning electron microscopic (SEM) images showed that the ceramic nanoparticles were homogeneously distributed throughout the hydrogel matrix. An antioxidant agent (i.e., ferulic acid) was loaded onto agarose/LDH and gelatin/LDH hybrids, and the time-dependent release of ferulic acid was investigated via high-performance liquid chromatography (HPLC) for kinetic model fitting. Conclusions: Biopolymer/LDH hybrid materials that were prepared by electrophoretic method created a homogeneous composite of two components and possessed controllable drug release properties according to the type of biopolymer.

The 2D transition metal carbides/nitrides (2D MXenes) are a versatile class of 2D materials for photovoltaic (PV) systems. The numerous advantages of MXenes, including their excellent metallic conductivity, high optical transmittance, solution processability, tunable work‐function, and hydrophilicity, make them suitable for deployment in PV technology. This comprehensive review focuses on the synthesis methodologies and properties of MXenes and MXene‐based materials for PV systems. Titanium carbide MXene (Ti₃C₂T_x), a well‐known member of the MXene family, has been studied in many PV applications. Herein, the effectiveness of Ti₃C₂T_x as an additive in different types of PV cells, and the synergetic impact of Ti₃C₂T_x as an interfacial material on the photovoltaic performance of PV cells, are systematically examined. Subsequently, the utilization of Ti₃C₂T_x as a transparent conductive electrode, and its influence on the stability of the PV cells, are discussed. This review also considers problems that emerged from previous studies, and provides guidelines for the further exploration of Ti₃C₂T_x and other members of the 2D MXene family in PV technology. This timely study is expected to provide comprehensive understanding of the current status of MXenes, and to set the direction for the future development in 2D material design and processing for PVs.

A methotrexate (MTX)-layered double hydroxide (LDH) hybrid have been developed as a drug delivery system, in which an anticancer drug, MTX, was intercalated into a 2-dimensional LDH nanovehicle to form a nanohybrid. According to the comparative cell viability studies between MTX only and its LDH nanohybrid on MTX sensitive and resistant cell culture lines, it was found that the MTX-LDH nanohybrid could bypass the MTX resistance and eventually inhibit cancer cell proliferation very effectively compared to free MTX, due to an enhanced permeability and retention effect of MTX-LDH nanoparticles even in dihydrofolate reductase-overexpressing MTX-resistant cells. This is definitely associated with the uptake mechanism via a clathrin-mediated endocytic pathway for the MTX-LDH nanohybrid particles, the same as for the LDH nanocarrier only, which is completely different from the cellular uptake mechanism for MTX only, the reduced folate carrier (RFC) and/or the folate receptor entries.

An attempt was made to control the surface charge of colloidal silica nanoparticles with 20 nm and 100 nm diameters. Untreated silica nanoparticles were determined to be highly negatively charged and have stable hydrodynamic sizes in a wide pH range. To change the surface to a positively charged form, various coating agents, such as amine containing molecules, multivalent metal cation, or amino acids, were used to treat the colloidal silica nanoparticles. Molecules with chelating amine sites were determined to have high affinity with the silica surface to make agglomerations or gel-like networks. Amino acid coatings resulted in relatively stable silica colloids with a modified surface charge. Three amino acid moiety coatings (L-serine, L-histidine, and L-arginine) exhibited surface charge modifying efficacy of L-histidine > L-arginine > L-serine and hydrodynamic size preservation efficacy of L-serine > L-arginine > L-histidine. The time dependent change in L-arginine coated colloidal silica was investigated by measuring the pattern of the backscattered light in a Turbiscan™. The results indicated that both the 20 nm and 100 nm L-arginine coated silica samples were fairly stable in terms of colloidal homogeneity, showing only slight coalescence and sedimentation.