Nanoparticles Based on Chitosan as Carriers for the Combined Herbicides Imazapic and Imazapyr

Abstract

The use of lower concentrations and fewer applications of herbicides is one of the prime objectives of the sustainable agriculture as it decreases the toxicity to non-targeted organisms and the risk of wider environmental contamination. In the present work, nanoparticles were developed for encapsulation of the herbicides imazapic and imazapyr. Alginate/chitosan and chitosan/tripolyphosphate nanoparticles were manufactured, and their physicochemical stability was evaluated. Determinations were made of the encapsulation efficiency and release kinetics, and the toxicity of the nanoparticles was evaluated using cytotoxicity and genotoxicity assays. The effects of herbicides and herbicide-loaded nanoparticles on soil microorganisms were studied in detail using real-time polymerase chain reactions. The nanoparticles showed an average size of 400 nm and remained stable during 30 days of storage at ambient temperature. Satisfactory encapsulation efficiencies of between 50 and 70% were achieved for both types of particles. Cytotoxicity assays showed that the encapsulated herbicides were less toxic, compared to the free compounds, and genotoxicity was decreased. Analyses of soil microbiota revealed changes in the bacteria of the soils exposed to the different treatments. Our study proves that encapsulation of the herbicides improved their mode of action and reduced their toxicity, indicating their suitability for use in future practical applications.

Interaction of Nanomaterials with Plants: What Do We Need for Real Applications in Agriculture?

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Design, optimization and characterization of coenzyme Q10- and D-panthenyl triacetate-loaded liposomes

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Safe nanotechnologies for increasing the effectiveness of environmentally friendly natural agrochemicals

“…It is well known as an elicitor of defence responses in plants and it possesses antifungal properties that make it very attractive for applications in plant protection . However, it can be used as a carrier for pesticides when synthesized in the form of nanoparticles, either alone or in combination with other polymers . This double function as nanocarrier and active substance itself, in addition to its origin from a waste by‐product from the fishing industry, turns chitosan into a promising material for nanoformulating natural compounds …”

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