Host-guest complex solid state molecular motion is a critical but underexplored phenomenon. In principle, it can be used to control molecular machines that function in the solid state. Here we describe a solid state system that operates on the basis of complexation between an all-hydrocarbon macrocycle, D 4d -CDMB-8, and perylene. Molecular motion in this solid state machine is induced by exposure to organic solvents or grinding and gives rise to different co-crystalline, mixed crystalline, or amorphous forms. Distinct time-dependent emissive responses are seen for different organic solvents as their respective vapours or when the solid forms are subject to grinding. This temporal feature allows the present D 4d -CDMB-8⊃perylene-based system to be used as a time-dependent, colour-based 4th dimension response element in pattern-based information codes. This work highlights how dynamic control over solid-state host-guest molecular motion may be used to induce a tuneable temporal response and provide materials with information storage capability.

BACKGROUND Molluscan shellfish, including oysters, often cause allergic reactions in sensitive people throughout the world. It has been demonstrated that arginine kinase (AK) is one of the major allergens of oyster. The present study aimed to evaluate the immunoreactivity and structure of oyster AK as affected by heat treatment, pH change, and in vitro digestion. What is more, the immunoglobulin E‐binding epitopes of this allergen were also predicted and validated. RESULTS Thermal and pH assays revealed that AK was unstable at temperature >40 °C or pH ≤5.0 by sodium dodecyl sulfate polyacrylamide gel electrophoresis and circular dichroism, and the digestibility assays suggested that AK was more easily digested by pepsin than by trypsin and chymotrypsin. The potential epitopes were predicted through immunoinformatics tools, and seven linear epitopes were identified by indirect competition enzyme‐linked immunosorbent assay with pooled sera and individual serum from oyster‐allergic patients. The critical amino acids in each epitope were also confirmed using mutant peptides. These linear epitopes and critical amino acids were apt to distribute on the outer surface of homology‐based AK model. Moreover, the three denaturants (sodium dodecyl sulfate, β‐mercaptoethanol, and urea) can destroy the spatial structure of AK and increase or reduce its allergenicity by denaturation treatments. CONCLUSION Processing conditions lay the foundation for the variation of allergenicity. Seven linear epitopes and their critical amino acids were identified by indirect competitive enzyme‐linked immunosorbent assay. These findings will be helpful in allergy diagnosis and development of hypoallergenic products in the near future. © 2021 Society of Chemical Industry.

We report a molecular switching ensemble whose states may be regulated in synergistic fashion by both protonation and photoirradiation. This allows hierarchical control in both a kinetic and thermodynamic sense. These pseudorotaxane-based molecular devices exploit the so-called Texas-sized molecular box (cyclo[2]-(2,6-di(1H-imidazol-1-yl)pyridine)[2](1,4-dimethylenebenzene); 14+, studied as its tetrakis-PF6− salt) as the wheel component. Anions of azobenzene-4,4′-dicarboxylic acid (2H+•2) or 4,4′-stilbenedicarboxylic acid (2H+•3) serve as the threading rod elements. The various forms of 2 and 3 (neutral, monoprotonated, and diprotonated) interact differently with 14+, as do the photoinduced cis or trans forms of these classic photoactive guests. The net result is a multimodal molecular switch that can be regulated in synergistic fashion through protonation/deprotonation and photoirradiation. The degree of guest protonation is the dominating control factor, with light acting as a secondary regulatory stimulus. The present dual input strategy provides a complement to more traditional orthogonal stimulus-based approaches to molecular switching and allows for the creation of nonbinary stimulus-responsive functional materials.

In this study, the effect of corn oligopeptides (COPs) with liver protection activity on mice with hepatic fibrosis (HF) induced by carbon tetrachloride (CCl4) was studied. It was proved that COPs can ameliorate the liver injury and inflammation caused by CCl4 by histopathology and enzyme‐linked immunosorbent assay in mice. The expression of Akt/NF‐κB inflammatory pathway was determined by real‐time polymerase chain reaction (RT‐PCR) and western blotting (WB). The results showed that COPs inhibited the expression of key proteins in the inflammatory pathway. In conclusion, the results of this study suggested that COPs could improve CCl4‐induced HF by improving liver injury, reducing the expression of inflammatory factors, and inhibiting the expression of inflammatory signaling pathways. Practical applications The corns around the world are mainly used as animal feed, and the liver protective activity of corn oligopeptides (COPs) is rarely applied to the market. The development of COPs liver protective food can prevent the occurrence of liver‐related diseases such as hepatic fibrosis to a certain extent. Developing COPs liver protecting food can improve the utilization value of corn. It is hoped that this study can provide experimental support for the application of COPs in liver protection food.