Cucurbit[7]uril-Mediated Supramolecular Bactericidal Nanoparticles: Their Assembly Process, Controlled Release, and Safe Treatment of Intractable Plant Bacterial Diseases

Abstract

A safe, biocompatible, and stimuli-responsive cucurbit [7]urilmediated supramolecular bactericidal nanoparticle was fabricated by encapsulating a highly bioactive carbazole-decorated imidazolium salt (A 1 , EC 50 = 0.647 μg/mL against phytopathogen Xanthomonas oryzae pv oryzae) into the host cucurbit[7]uril (CB[7]), thereby leading to self-assembled topographies from microsheets (A 1 ) to nanospheroidal architectures (A 1 @ CB[7]). The assembly behaviors were elucidated by acquired single-crystal structures, 1 H NMR, ITC, and X-ray powder diffraction experiments. Complex A 1 @CB[7] displayed lower phytotoxicity and could efficiently switch on its potent antibacterial ability via introducing a simple competitor 1-adamantanamine hydrochloride (AD). In vivo antibacterial trials against rice bacterial blight revealed that A 1 @CB[7] could relieve the disease symptoms after being triggered by AD and provide a workable control efficiency of 42.6% at 100 μg/mL, which was superior to bismerthiazol (33.4%). These materials can provide a viable platform for fabricating diverse stimuli-responsive supramolecular bactericides for managing bacterial infections with improved safety.

Making the Complicated Simple: A Minimizing Carrier Strategy on Innovative Nanopesticides

“…The development of these functions mostly comes from the addition of exogenous compounds, so both NMC and NNC are easy to implement. Importantly, the stimulus-responsive capability of NMC can also be attributed to the reversibility of the structures formed through self-assembly, enabling NMC to response to environmental factors such as temperature and pH [ 45 , 46 ]. Another potential advantage of NMC is cost-effectiveness, mainly attributed to exclude large-scale manufacturing of carriers and the improvement of efficacy.…”

“…4 B, the researchers initially synthesized a hydrophobic azobenzene derivative ( Trans -G), then created an amphiphilic ternary complex involving paraquat, Trans -G, and cucurbit[ 8 ]uril in water. Finally, the complex formed hollow spheres through self-assembly, which also capable of loading active substances, and achieved responsive release under ultraviolet light through the trans -to- cis isomerization of Trans -G. In a recent study by Ji et al [ 45 ], highly bioactive carbazole-modified amphiphilic quaternary ammonium salts with cationic N -benzylimidazolium pendants were prepared. Then, the host cucurbit[ 7 ]uril was introduced to construct a supramolecular system, regulating its release by the addition of competitive molecules (such as 1-adamantanamine hydrochloride).…”

Photo‐Stimuli Smart Supramolecular Self‐Assembly of Azobenzene/β‐Cyclodextrin Inclusion Complex for Controlling Plant Bacterial Diseases

“…[17,27,28] This contribution suggests that rational fabrication of cyclodextrins-based binary complexes has significant application prospects to improve the bioavailability and stability of the active ingredients and endows novel delivery systems to reasonably release active ingredients. [29][30][31][32] Azobenzene analogs are a family of compounds that can be encapsulated by loading cyclodextrins with noncovalent interactions. [33,34] This type of molecule has a unique photoresponsive property that coexists in both cis-and transconfigurations, and can be reversed under different illumination conditions.…”

“…[ 17,27,28 ] This contribution suggests that rational fabrication of cyclodextrins‐based binary complexes has significant application prospects to improve the bioavailability and stability of the active ingredients and endows novel delivery systems to reasonably release active ingredients. [ 29–32 ]…”

Green Nanopesticide: pH-Responsive Eco-Friendly Pillar[5]arene-Modified Selenium Nanoparticles for Smart Delivery of Carbendazim to Suppress Sclerotinia Diseases

“…Proper supplementation of selenium can improve human immunity and resist various diseases. − Selenium nanoparticles (Se NPs) also showed an excellent therapeutic effect in Alzheimer’s disease and drug-resistant bacteria. − However, there is no report on applying Se NPs to control plant pathogenic fungi . Supramolecular macrocycles, including cyclodextrin, cucurbiturils, calixarenes, and pillararenes, have been widely used in many fields, such as pesticide determination, controlled release of pesticides, , reduction of pesticide toxicity, recognition of drug chirality, and biosensors . Pillar­[ n ]­arenes have the advantages of p-rich cavities, symmetrical rigid architectures, and good biocompatibility.…”