Moisture-Catalyzed Slow Release of Sex Pheromone from Microcrystals in Controlling Phyllophaga Pests

Abstract

Pheromones form Primary Ammonium Monocarboxylate (PAM) synthons based supramolecular container of sex pheromone to control Phyllopaga pests in greenway. Therein charge-assisted H-bonds are highly stable in aprotic solvents like diethyl ether, dichloromethane, or chloroform, but protic solvent like water disintegrates it even in the moisture state. By preparing the micro-thin needle-shaped supramolecular container, we released sex pheromone under an open atmosphere. Herein, the labile proton in PAM salt drifts from amino acid methyl ester ammonium to carboxylate moiety under moisturized open environment before releasing the pheromone. This moisture-driven pheromone releasing device could be used to trap the pests physically. The nuclear magnetic resonance (NMR) spectroscopy showed the first-order kinetics while releasing the sex pheromone from the supramolecular container in moist air. The density functional theory (DFT) and experimental studies described here establish the green method of releasing the sex pheromone to trap the pests physically. This method could open a window towards pesticide-free green organic farming.

Space and Time Crystal Engineering in Developing Futuristic Chemical Technology

“…Often these reactions are uncontrollable and compete with each other. For example, controlling water oxidation [38,39] and CO2 reduction often becomes a challenge, as these compete with hydrogen evolution reactions. As CO2 is a stable molecule (bond enthalpy: +805 kJ/mol), the reduction reaction of CO2 is an uphill process (ΔG 0 > 0).…”

pH-Responsive Intelligent Antibacterial Coatings Based on 2D-COF for Controlled Release of Capsaicin

“…At present, the main methods of intelligently controlling the release of antifouling agents are pH response, enzyme response, and temperature response . Up to now, a variety of nanomaterials with good controlled-release properties have been reported, including poly­(vinyl alcohol) microspheres in a silk sericin-based hydrogel, composite films with an adjustable number of layers using sodium alginate (SA), chitosan (CS), and activated charcoal (AC), microcrystals, polyvinyl alcohol/chitosan microspheres, and a selenium-rich tea set. , Chitosan (CS) has antibacterial properties due to the interaction between its positively charged amino group and the negatively charged cell membrane of bacteria. , The nanocapsules made from CS exhibit typical pH response characteristics due to the large number of amino groups contained in the side chain. , In addition, the intelligent delivery of fungicides can be realized by the modification of chitosan. , Our research group has developed a capsaicin@chitosan (CAP@CS) microcapsule with pH response performance, which can realize the intelligent controlled release of the natural bactericide CAP, which plays an effective sterilization and antifouling role. , However, its dispersion is limited. In order to improve the dispersion on the basis of pH response sterilization, we hope to introduce other materials to further improve the performance of intelligent response controlled release sterilization. , Two-dimensional materials (graphene, covalent organic frameworks) have great potential for marine protective materials, such as corrosion protection and fouling protection, due to their excellent adsorption characteristics, mechanical strength, thermal stability, and other characteristics. , In recent years, 2D covalent organic frameworks (COFs), which are typical representatives of 2D nanomaterials, have the characteristics of diverse synthesis methods, large specific surface area, stable physical and chemical properties, and broad application prospects in different fields. , COF-MOF hybrid materials have ingenious and obvious structural characteristics and excellent performance .…”

“…25,26 At present, the main methods of intelligently controlling the release of antifouling agents are pH response, 24 enzyme response, 27 and temperature response. 28 Up to now, a variety of nanomaterials with good controlled-release properties have been reported, including poly(vinyl alcohol) microspheres in a silk sericin-based hydrogel, 29 composite films with an adjustable number of layers using sodium alginate (SA), chitosan (CS), and activated charcoal (AC), 30 microcrystals, 31 polyvinyl alcohol/chitosan microspheres, 32 and a selenium-rich tea set. 33,34 Chitosan (CS) has antibacterial properties due to the interaction between its positively charged amino group and the negatively charged cell membrane of bacteria.…”

Unveiling Discotic Liquid Crystalline Phase Changes through Supramolecular Disc Polymorphism at Their Disc-Driven Gel State

“…Thus, it cannot display the LC properties. Similarly, primary ammonium monocarboxylate (PAM) 8 does not exhibit the temperature-dependent crystalline phase changing efficiency (Scheme 1c).…”

“…In the presence of an external electromagnetic field, supramolecular bonds would not disintegrate to align themselves like liquid crystals. Thus, the prominent inherent force from supramolecular bonding will produce supramolecular shapes in supramolecular gels, , metal–organic frameworks, self-healing crystals, pheromone-container, etc., and the external field will orient molecules in one dimension in forming the liquid crystals. For these two opposite molecular properties, a molecule either can self-assemble by its internal supramolecular force to form a gel or can be aligned to form an LC under an external field.…”