Interaction of pesticide pyroquilon with two different cucurbitnuril

摘要

In this work, we report a conceptual strategy for preventing pesticide degradation using cucurbitnuril to encapsulate pyroquilon (Pyn). The host-guest inclusion complexes of pyroquilon (Pyn) with CB7 and CB8 were prepared and characterized using H-1 NMR spectroscopy, quadrupole-time of flight mass spectrometry (Q-TOF), isothermal titration calorimetry (ITC) and UV absorbance spectrophotometry. The experimental results revealed that the entire Pyn molecule resides within the cavities of CB7 and CB8, forming 1:1 inclusion complexes between CBn and Pyn. Our study on the release of Pyn demonstrated that CBn@Pyn exhibit sustained- and slow-release properties. Moreover, CB8 can effectively shield UV irradiation and thereby protect the Pyn from photodegradation. Therefore, CB7@Pyn and CB8@Pyn have great potential to be used as slow-release agents.