One-step synthesis of methyl eugenol/Schiff base mesoporous silica nanoparticles sustained-release performance with high lure efficiency

The mesoporous silica nanoparticles (MSN) was modified by salicylaldimine, furfuralimine, and benzaldehyde imine, respectively, denoted as Sal-MSN, Fur-MSN, and Ben-MSN for methyl eugenol (Me) delivery by one-step method. The results confirmed that Me was successfully adsorbed by Schiff base mesoporous silica, which maintained regular hexagonal pore structure. Me is distributed in amorphous state in the pores of the mesoporous silica indicated by differential scanning calorimeter (DSC) curves. Schiff base modification strengthened the interaction between Me and mesoporous silica, leading to its higher sustained-release performance and the disappearance of sudden release in sustained-release performance comparing with Me-MSN before Schiff base modification. Me and Me-MSN were most consistent with the First-order kinetic and logistic equation, respectively. After Schiff base modification, Me-Sal-MSN, Me-Fur-MSN, and Me-Ben-MSN were most consistent with Korsmeryer–Peppas kinetic equation. Therefore, the difference of Me concentration was no longer the main control factor of sustained-release system after Schiff base modification. In the attraction of Bactrocera dorsalis test, the lure efficiency for per unit Me for Me-MSN, Me-Sal-MSN, Me-Fur-MSN, and Me-Ben-MSN equal to 2.83, 3.31, 3.32, 4.24 times of pure Me. After Schiff base modification, the samples showed higher lure efficiency due to their ideal sustained-release performance without sudden release. In short, the lure efficiency of Me was improved by the Schiff base mesoporous silica sustained-release system, in the meanwhile its service life was also prolonged.