For the first time, this paper revealed that 2-picoline borane (pic-BH₃) functioned well in the reductive amination of chitosan. Therefore, N-benzyl chitosan with a nearly perfect degree of substitution was successfully obtained, which has rarely been achieved by other synthetic methods. The new method herein has many advantages, including being more facile, more efficient, and less harmful than conventional methods; thus, this method is applicable to other aldehydes or ketones, leading to a wide variety of N-modified chitosan specimens with desirable degrees of substitution in the future.

This study proposes a semiautomated system for synthesizing polyamic acid particles using a custom liquid-handling device and a robotic arm. Integrating cameras and a multimodal large language model enhances continuous monitoring and documentation, improving objectivity in synthetic experiments and enabling future advancements in research.

Blends of poly(lactic acid) (PLA) and thermoplastic starch (TPS) are promising biodegradable plastics, although their poor compatibility results in poor physical properties. In this study, oligo(lactic acid)-grafted starch (OLAgSt) was synthesized and added to PLA/TPS blends as a compatibilizer, and the physical properties of the obtained blends were evaluated. OLAgSt was synthesized by ring-opening polymerization of L-lactide using the hydroxy group of tapioca starch as an initiator. OLAgSt not only enhanced the dispersion of TPS within PLA, but also improved the biodegradability of the blend in a seawater environment.

The gel-phase diagrams of temperature-responsive and biocompatible polymers with ethylene oxide (EO) side chains that differ in length were obtained. The gelation thresholds of the polymers depend not only on the monomer and crosslinker concentrations but also on the EO side chain lengths. Long EO side chains reduce the polymer overlap concentration. Furthermore, the EO side chains can engage in self-crosslinking, i.e., polymers can grow from the side chains depending on their length. These unique behaviors indicate that gelation occurs more readily with increasing the side chain length.

Induction of helical structures in peptides have been shown to increase their membrane permeability and facilitate cargo delivery applications. Our study has shown that substitution of an unnatural amino acid into a mitochondrial-targeting peptide induces a helical conformation that is maintained even after conjugation onto carbon nanotubes and confers increased membrane permeability. This led to an increase in DNA delivery efficiencies and gene expression into the mitochondria of intact plants when used as a DNA delivery system.

Optical resonators have attracted renewed attention in chemistry and biology as minute and highly sensitive sensors that work in the environment and inside biological tissues and cells without any connected wires. Optical resonators should be functional for facilitating molecular interactions and biological compatibility, which is, however, challenging with conventional materials and processing techniques. In contrast, the authors have been tackling this issue by using supramolecular chemistry. This article reviews our recent progress on the methodologies for making organic optical resonators and their emergent optical properties.

This study developed a novel method for the control of the cellulose crystal of cellulose I and II. The crystal transition from cellulose I to II was tracked when cellulose I, which is soaked in a low-concentration NaOH aqueous solution, was quenched using liquid nitrogen. The crystal transition progressed from the surface to the center of the sample. This quench treatment has the potential to fabricate new cellulose materials with a cellulose I core and a cellulose II surface.

This study presented the workflow of machine learning-guided optimization of Pd-immobilized porous polymer catalysts. Two independent variables (DVB and 1-decanol content) were involved in polymerization to maximize TOF as target variable in Suzuki–Miyaura coupling reaction. Bayesian optimization was applied for predictive modeling, and the optimized conditions were experimentally validated in subsequent iterations. By applying this workflow, the catalytic activity of immobilized polymer porous catalysts was successfully optimized using machine learning.

The crystalline surface using two photochromic diarylethenes was prepared to mimic a termite wing showing dual wettability. The surface is useful to correct small water droplets in the air. However, the crystalline system was not applicable for the use because crystalline structures on the surface melt under daylight. We copied the rough structure of crystalline film to a stable polycycloolefin polymer (Zeonex 480) surface. The copied surface showed the dual wettability as same as that of the crystalline surface.