Design, characterization, and evaluation of eco-friendly etofenprox-loaded ethosomes to control Ceratitis capitata (Diptera: Tephritidae)

TL;DR

This study develops a safer, eco-friendly pesticide formulation using ethosomes to control fruit flies, showing improved performance and reduced environmental impact.

Contribution

The paper introduces an innovative etofenprox-loaded ethosome formulation for agricultural pest control with enhanced safety and efficacy.

Findings

Etofenprox-loaded ethosomes showed slower release and higher residue retention on lemon leaves compared to commercial formulations.

Geraniol-ethosomes exhibited prolonged toxicity against fruit flies and were non-toxic to human cells.

The formulation remained stable for 90 days and could reduce pesticide application doses in pre-fruiting stages.

Abstract

Ceratitis capitata, is one of the most considerable invasive pests affecting fruit production worldwide. Conventional pesticides are generally formulated using organic solvents and emulsifiers that, in turn, are flammable and toxic. Thanks to their small size and biocompatibility, liposome-like formulations may significantly improve the efficacy and safety of conventional pesticides. This study aims to develop an alternative and innovative etofenprox formulation based on phospholipid vesicles (ethosomes) and evaluate its possible application for agricultural pest control. Ethosomes and geraniol-ethosomes were prepared by the one-step sonication method, achieving vesicles with small sizes (around 267 nm) and low polydispersity index (around 0.04). These vesicles were stable over 90 days of storage at room temperature and could slow the release of etofenprox (57 ± 4% released), in comparison with a commercial formulation (85 ± 5% released) after 24 h. Ethosomes and geraniol-ethosomes showed similar retention properties on lemon leaves (13.3 ± 1.0 to 14.4 ± 1.2 mg/cm2) under laboratory condition. After open-field application, geraniol-ethosomes left the highest etofenprox residues on lemon leaves (14.3 ± 1.0 mg/kg), whereas the commercial formulation on the flavedo (4.1 ± 0.5 mg/kg). This result highlighted the possibility of reducing the application dose of etofenprox loaded in geraniol-ethosomes especially during the BBCH stage before fruiting. Both formulations displayed good biocompatibility with no significant cytotoxic effects on human keratinocytes (HaCat cells) across different etofenprox concentrations. Furthermore, laboratory bioassays revealed that geraniol-ethosomes exhibited a prolonged toxicity when sprayed against Ceratitis capitata adults, attributed to sustained release kinetics, underscoring their potential in environmentally sustainable agricultural pest management.

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