Korea Institute of Ceramic Engineering and Technology

Biologically active glasses (BG) are widely studied as potential materials for bone tissue engineering, owing to their capacity to form hydroxyapatite (HA) layers when exposed to body fluids. However, the demerit of BG is the slow deposition rate of calcium ions on the surface, a key factor in increasing the conversion rate to mineralization. The purpose of this study is to introduce phosphoryl group recognized as a trigger for the nucleation processes of apatite formation on the surface of BG. BG was coated with poly (2-methacryloyloxyethyl phosphorylcholine) (PMB) and characterized via Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). Biomimetic mineralization was evaluated through simulated body fluid (SBF) immersion, X-ray diffraction (XRD). In vitro MG-63 cell responses were assessed and compared among BG, BG/HA, BG/2%PMB, and BG/2%PMB/HA groups. Results demonstrated that the PMB coating successfully promoted mineralization by introducing negatively charged phosphate groups that enhanced crystallization. BG/2%PMB/HA significantly upregulated focal adhesion markers in MG-63 cells, likely due to improved fibronectin (Fn) deposition on the HA layer. Furthermore, the BG/2%PMB/HA surface enhanced cell survival and proliferation through crosstalk with integrin-mediated signaling pathways. PMB-coated BG effectively accelerates biomimetic mineralization and regulates cellular responses, making it a promising candidate for bone regeneration applications.

This study investigates the effect of halloysite nanotubes (HNT) on mitigating moisture absorption and the associated mechanical degradation in epoxy-based carbon fiber–reinforced plastics (CFRP) under prolonged exposure to water environments. HNT are nanoadditives known to enhance both moisture resistance and mechanical properties. CFRP specimens containing 1 and 5[Formula: see text]wt.% HNT were fabricated, and their moisture absorption behavior, mechanical property changes and fracture surface morphologies were evaluated. Moisture absorption tests conducted in 70 ∘ C distilled water for 90 days revealed that the incorporation of HNT reduced the moisture absorption rate of CFRP by up to 30%. Mechanical testing showed that the addition of 1[Formula: see text]wt.% HNT improved flexural strength and interlaminar shear strength by approximately 6%, effectively mitigating property degradation following moisture exposure. Fracture surface analysis indicated improved fiber–matrix interfacial bonding due to the presence of HNT, contributing to the retention of mechanical performance. Furthermore, a deep-learning-based prediction model was developed and validated against experimental data to predict the moisture absorption and mechanical property changes of CFRP containing 2–4[Formula: see text]wt.% HNT. These findings demonstrate that incorporating HNT is effective in enhancing the moisture resistance and mechanical durability of CFRP.

Triboelectrification has been known for millennia and remains of great practical importance, with applications spanning pharmaceuticals, electronics, industrial processes, and especially energy harvesting. Its inherent complexity, however, has long hindered a definitive understanding. In recent years, the advent of triboelectric nanogenerators (TENGs) has stimulated extensive experimental investigations and, in parallel, the development of promising first-principles-based theoretical models. Together, these advances have begun to clarify fundamental aspects of triboelectric charge transfer. This review traces the progression from early electron-transfer concepts to recent frameworks, including the backflow-stuck charges, thermoelectric, flexoelectric, and mechanochemical models. We discuss their evolution, the problems they address, the discoveries and insights they have enabled, as well as their limitations. At the beginning of the manuscript, special emphasis is given to the development of TENGs, which have both advanced practical applications and uncovered new triboelectric phenomena. Finally, we identify key open challenges and provide an outlook on future directions. The integration of complementary models through multiscale approaches, supported by systematic experimental validation, offers the most promising pathway toward a comprehensive understanding of this long-standing problem and the rational design of triboelectric materials and devices.

Single-chain variable fragments (scFvs) antibodies are used in diagnostic and therapeutic biopharmaceuticals. However, its production is limited due to insoluble expression and lack of a universal purification ligand. Here, we report a novel two-in-one protein tag, termed CSQ-tag, utilizing a calsequestrin (CSQ) protein to enable the soluble expression and calcium-dependent purification for scFvs. The CSQ-tag enhanced the solubility of four different therapeutic scFvs with an average solubility of 83.8 ± 4.6% in the BL21(DE3) strain, despite its reducing cytoplasmic environment. Compared to other tags, CSQ-tag showed superior solubility, with 1.8-fold higher solubility than MBP-tag across four scFvs. The solubility enhancement of the CSQ-tag is attributed to two main characteristics: highly acidic sequences with a low isoelectric point of 3.95, and intrinsically disordered protein properties. Furthermore, CSQ-tag can cost-effectively purify therapeutic scFvs with high purity over 95% using the calcium-dependent phase transition properties. Importantly, the anti-VEGF-scFv produced with the CSQ-tag showed a binding affinity of 25.8 pM, similar to that of the existing therapeutic brolucizumab. Therefore, CSQ-tag can significantly improve productivity and simultaneously maintain scFvs' functional integrity, thereby serving as a promising tool for universal expression and purification of therapeutic scFvs.

Alumina ceramics used in semiconductor plasma environments require high densification, microstructural homogeneity, and stable performance under increasingly aggressive processing conditions. However, systematic studies linking slurry processing parameters to the plasma resistance of alumina ceramics remain limited. In this study, the effects of slurry preparation parameters—specifically milling and aging—and sintering atmosphere on the densification, mechanical strength, and plasma etching resistance of slip-cast alumina ceramics were systematically investigated. Optimal dispersion stability was achieved under 12 h milling and 12–24 h aging conditions, resulting in homogenized green body packing and a high relative sintered density exceeding 99%. Mechanical strength and plasma resistance were strongly influenced by slurry aging and sintering atmosphere. Specimens aged for 48 h and sintered under a low oxygen partial pressure (N2 at 1.0 L/min) exhibited the highest flexural strength and significantly improved resistance to SF6/Ar plasma etching, with reduced etch depth and suppressed surface roughening. These results demonstrate that coordinated slurry processing and sintering atmosphere control is an effective strategy for designing high-reliability, plasma-resistant alumina ceramics for high-demand semiconductor manufacturing environments.

Oxide-based garnet-type solid electrolytes are promising for next-generation all-solid-state batteries owing to their high lithium-ionic conductivity and excellent chemical stability. However, high-temperature sintering is typically required for sufficient densification, which can cause lithium loss, phase instability, and reduced conductivity. In this study, the effects of two typical lithium precursors, lithium carbonate (LC) and lithium hydroxide monohydrate (LH), on the powder characteristics, phase formation, microstructure, and electrochemical performance of Li6.4La3Zr1.4Ta0.6O12 (LLZT) were systematically compared. LH-based LLZT demonstrated high-phase purity, fine and uniform particles, and good sinterability. In contrast, LC-based LLZT exhibited larger particles and broader distribution, leading to poor densification. To address this, a sintering additive was applied to LC-based LLZT, achieving a high relative density of 97.0% at 1100 ℃, comparable to that of LH-based LLZT. Its ionic conductivity reached 4.40 × 10–4 S/cm at 25 ℃, with a low electronic conductivity (7.59 × 10–9 S/cm), confirming good insulation. This work demonstrates that the choice of lithium precursor and sintering additives significantly influences the phase stability and microstructure of garnet-type electrolytes. A practical approach is suggested to enhance the electrolyte performance using cost-effective LC precursors, which can support the scalable production of oxide-based solid electrolytes for safer all-solid-state batteries.