Water-soluble stimuli-responsive supramolecular nanoagrochemicals based on macrocycle compounds

Agrochemicals are extensively utilized to ameliorate agricultural yield and quality, but they also negatively impact ecological cycle and human health as a consequence of indiscriminate pesticide usage and growing anthropogenic interference. To improve the efficiency and biosafety of existing agrochemicals, the dynamic and reversible nature of host–guest complexation with water-soluble macrocycles has been fully exploited in supramolecular chemistry to construct fascinating nanoassemblies with environmental stimuli-responsiveness. This review mainly focuses on (i) the performance-directed molecular recognition properties of common cavity-bearing macrocycles, including crown ethers, cyclodextrins, calixarenes, cucurbiturils, and pillararenes, toward a wide range of agroactive ingredients; (ii) the developmental updates in the emerging realm of macrocycle-based multistimuli-responsive supramolecular nanoagrochemicals, with an emphasis on their molecular basis, operation mechanism, and application toward a series of chemical (pH and redox), physical (photo and temperature), and biological (enzyme and reactive oxygen species) factors as internal and external stimuli relevant to plants and pests; and (iii) the encumbered challenges and perspectives on the translational development of these environmentally adaptive nanomaterials under realistic field conditions. In the wave of intelligentization of modern agricultural practices, we believe the stimuli-responsive supramolecular nanoagrochemicals is now spurring the impending agri-tech revolution at a global scale.