|
Abstract
|
In order to study the oviposition deterrency and insecticidal activity of Mentha longifolia microencapsulated essential oil on Tuta absoluta (Meyrick) (Lepidoptera:Gelechiidae) under laboratory conditions of 25 ± 1 °C and 70 ± 10% R.H. and a photoperiod of 16:8 h (L:D), essential oil from this plant species was extracted by Clevenger-type water distillation, and analyzed using gas chromatography-mass spectrometry. In the present study, nano hollow silica spheres were synthesized by sol-gel method as a Mentha longifolia essential oil carrier, and functionalized with thiol groups. Sulfonic acid functionalized hollow silica spheres were further obtained by oxidation of thiol function to sulfonic acid groups. Hollow silica/magnetic spheres were subsequently prepared using sulfonic acid hollow silica spheres as template. The Fe3O4 nanoparticles were then deposited on the hollow silica shells by a coprecipitation reaction.The success of Mentha longifolia essential oil encapsulation was clarified by Fourier transform infrared (FT-IR) spectroscopy, Energy Dispersive X-ray Microanalysis (EDX), ultraviolet–visible (UV–vis) spectrophotometry, thermal gravimetry analysis (TGA), and X-ray diffraction (XRD) techniques. In addition, the shape and size of the particles have been determined by scanning electron microscopy (SEM) and transmission electron microscopy (TEM).
|