Open AccessPreparation, characterisation, and controlled release of sex pheromone-loaded MPEG-PCL diblock copolymer micelles for Spodoptera litura (Lepidoptera: Noctuidae)
Author(s) -
Yixin Chen,
Xiuqin Chen,
Yong Chen,
Hui Wei,
Shuo Lin,
Haihua Tian,
Tao Lin,
Jiuran Zhao,
Xing Gu
Publication year - 2018
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0203062
Subject(s) - spodoptera litura , micelle , noctuidae , copolymer , sex pheromone , materials science , lepidoptera genitalia , ethylene oxide , polymer chemistry , chemical engineering , chemistry , chromatography , organic chemistry , biology , composite material , botany , aqueous solution , polymer , engineering
Sex pheromones are important for agricultural pest control. The main sex pheromone components of Spodoptera litura are (Z,E)-9,11- and (Z,E)-9,12-tetradecadienyl acetate (Z9,E11-14:Ac; Z9,E12-14:Ac). In this study, we investigated the optimal conditions for encapsulation of S . litura sex pheromonesin micelles via the self-assembly method using monomethoxy poly (ethylene glycol)-poly (ε-caprolactone) (MPEG-PCL) as a biodegradable wall-forming material with low toxicity. In the L 9 (3 4 ) orthogonal experiment, 3 amphiphilic block copolymers, with different hydrophilicity to hydrophobicity ratios, were examined. Optimal encapsulation conditions included stirring of MPEG 5000 -PCL 2000 at 1000 rpm at 30°C with 2.5:1 wall-forming: core material mass ratio. S . litura sex pheromone-loaded MPEG 5000 -PCL 2000 micelles presented a homogeneous spherical morphology with apparent core-shell structure. The release kinetics of optimized MPEG 5000 -PCL 2000 micelles was best explained by a first-order model. Encapsulated Z9,E11-14:Ac and Z9,E12-14:Ac were released slowly, not suddenly. Methyl oleate (MO) was used as an agent to control micellar release performance. When MO content equalled block content, micelle half-life could be prolonged, thereby controlling the release speed. Overall, our results showed MPEG-PCL as a promising controlled-release substrate for sex pheromones.