Nanoemulsified essential oils as next-generation insecticides: preparation, enhanced efficacy, and future prospects

Abstract Insect pest infestations are a major problem that diminishes agricultural productivity and harms human habitats. Excessive reliance on synthetic insecticides contaminates the environment, food, and aquatic life, and harms human health. Even some of the insect species have become resistant to chemical insecticides. Essential oils (EOs) from the different aromatic plants exhibit promising insecticidal activity. However, their effectiveness is often hindered by volatility and instability. Nanotechnology offers significant opportunities for green insecticides. Nanoemulsions (NEs) made from EOs enhance the physicochemical properties of EOs, improving their bioactivity and targeting capabilities while minimizing harm to non-targeted organisms. This review covers the various preparation methods for nanoemulsions, characterization techniques, and the mechanisms of action against insect pests. The finding indicates that essential oil-based nanoemulsions (EONEs) possess significant insecticidal activity, outperforming traditional formulations in several studies. Further future directions are discussed, emphasizing the need for additional research on production feasibility, regulatory compliance, and ecological impact to facilitate the commercial application of these bioinsecticides. Overall, this review underscores the potential of nanoformulations as a viable, eco-friendly solution for pest management.