Improved Wettability and Spreading Behavior of Pesticides by <i>para</i>-Sulfonatocalix[4]arene and Chitosan Nanovesicles

Improving pesticide deposition on hydrophobic leaves is crucial for effective weed control and for minimizing the excessive use of pesticides in agriculture. This work explores the potential of para-sulfonatocalix[4]arene (SCX[4]) and chitosan (Cht) nanovesicles to enhance wettability and spreading, thereby improving pesticide performance. To achieve this, (SCX[4] + Cht) as a Paraquat (PQ) delivery carrier was synthesized and studied. UV–vis spectroscopy, TEM, DLS, and zeta potential analysis were employed to characterize and confirm the synthesis of the designed nanocarrier. Physical properties, such as contact angle, wetting, and spreading behavior of the PQ-loaded nanocarrier, were evaluated. The results showed that the physical properties of PQ improved after being encapsulated within the supramolecular vesicle compared to bare PQ. The study demonstrated that PQ is well encapsulated within (SCX[4] + Cht) nanocarriers, with an encapsulation efficiency 50.70% and a loading efficiency of 3.74%. The confocal laser scanning microscopy technique and EDS analysis were used to study the deposition behavior of the PQ-loaded nanocarrier on barnyard grass leaves. Additionally, the in vivo herbicidal activity of the pesticide-loaded carrier (SCX[4] + Cht)@PQ was evaluated against barnyard grass and Setaria within 5 days, revealing that the incorporation of SCX[4] and Cht components in the nanocarrier fabrication resulted in enhanced pesticidal performance of PQ. Encapsulating PQ within the nanocarrier significantly reduced its toxicity toward zebrafish, resulting in a 90% increase in the survival rate.