Issue 9, 2013

Preparation and characterization of double-shelled avermectin microcapsules based on copolymermatrix of silica–glutaraldehyde–chitosan

Abstract

Controlled release formulation (CRF) of pesticides is highly desirable for attaining the most effective utilization of the pesticide as well as reducing environmental pollution. Due to the selective permeation and protection properties of the semi-permeable membrane, pesticide microcapsules have been widely used. In this work, we developed a novel two-step method for synthesizing highly stable silica–glutaraldehydechitosan composite avermectin microcapsules. The silica shell was formed through the hydrolysis and polycondensation of tetraethyl orthosilicate (TEOS) at the oil droplet–water interface by using TEOS as the silica precursor and hexadecyl trimethyl ammonium chloride as a surfactant. Then the silica shell was modified with 3-aminopropyltriethoxysilane. Chitosan nanospheres were prepared by adjusting the pH value of the solution and then cross-linking with modified silica at the surface of the silica shell in the presence of glutaraldehyde to form double-shelled avermectin microcapsules. The results showed that the resulting microcapsules had a remarkable loading ability for avermectin (about 40% w/w) and can protect avermectin against photo- and thermal degradation effectively. Compared to single-shelled microcapsules, the double-shelled ones had better controlled release properties under all conditions. The present study provides a novel CRF comprising a pesticide which is light-sensitive or high temperature-sensitive, and a method for preparing the improved pesticide formulation so that the pesticide release rate and release period could be adjusted.

Graphical abstract: Preparation and characterization of double-shelled avermectin microcapsules based on copolymer matrix of silica–glutaraldehyde–chitosan

Article information

Article type
Paper
Submitted
11 Oct 2012
Accepted
02 Jan 2013
First published
04 Jan 2013

J. Mater. Chem. B, 2013,1, 1270-1278

Preparation and characterization of double-shelled avermectin microcapsules based on copolymer matrix of silica–glutaraldehydechitosan

S. He, W. Zhang, D. Li, P. Li, Y. Zhu, M. Ao, J. Li and Y. Cao, J. Mater. Chem. B, 2013, 1, 1270 DOI: 10.1039/C2TB00234E

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements