Insecticidal activity of polycaprolactone nanoparticles decorated with chitosan containing two essential oils against Tribolium confusum

Abstract

Essential oils are composed of volatile components, and rapidly evaporate. It is desirable to formulate them in a cover protecting the essential oils against environmental conditions. Applying nanotechnology to preparing desirable formulations of essential oils can be provided in a cover along with controlled release, increased oil life and greater mobility. In this study, nanoparticles were prepared using polycaprolactone and chitosan aimed at encapsulation of Rosmarinus officinalis and Zataria multiflora essential oils. The nanoparticles were characterized in terms of size, polydispersity, encapsulation efficiency, and scanning electron microscope photomicrographs. The nanoparticles showed a positive surface charge ranging between +11.60 and +29.20 mV and a mean particle radius ranging between 181-407 nm. Encapsulation efficiency was obtained between 75.8-84.4% under different preparation conditions. The LC₅₀ values of fumigant toxicity of R. officinalis essential oil and nanoparticles were equal to 103.53 and 112.64 μL/L air, and for Z. multiflora essential oil and nanoparticles, they were equal to 195.13 and 206.66 μL/L air, respectively for 24 h exposure time against Tribolium confusum. The effectiveness of non- formulated essential oils was significantly (P < 0.05) lower than nanoencapsulated oils in the confused flour beetle adults for a long period under the same condition, due to the sustained release of the essentials provided by the formulation.

Keywords:

• Nanoparticles
• encapsulation
• rosemary
• insecticide
• essential oil

Disclosure statement

The authors declare that they have no conflict of interest.

Author contribution statement

SMA and KTJ conceived the original idea and wrote the initial version. SMA, KTJ and GHA collected and analyzed the data. All the authors contributed in the final version of the manuscript.

Data availability statement

The authors confirm that the data supporting the findings of this study are available within the article and its supplementary information file.

Additional information

Funding

The authors acknowledge University of Tehran and Iran Nanotechnology Innovation Council (Project 97699) for funding.