Nanosensors\nfor Detecting Volatile Compounds in Pest\nManagement: A Focus on Agricultural Sustainability

Traditional pest management strategies, such as indiscriminate\npesticide use, have adverse environmental and human health implications.\nAs a sustainable alternative, this research focuses on employing nanosensors\nfor the detection of semiochemicals, including pheromones and defensive\ncompounds, released by stink bugs. These nanosensors feature a nanohybrid\nlayer of polyaniline and silver (PANI.Ag) and a nanocomposite of polyaniline\nand graphene oxide (PANI/GO). The study explores the detection of\nsynthetic semiochemicals, including <i>cis</i> and <i>trans</i> bisabolene epoxides, (<i>E</i>)-2-hexanal,\n(<i>E</i>)-2-decenal, (<i>E</i>)-2-octenyl acetate,\nand (<i>E</i>)-2-octenal semiochemicals emitted by Nezara viridula (Southern green stink bug) in the\nreal environment. The sensing layer characterization showed differences\nin hydrophilicity and surface roughness between the PANI.Ag and PANI/GO\nlayers. When exposed to synthetic compounds like <i>cis</i> and <i>trans</i> bisabolene epoxides, (<i>E</i>)-2-hexanal, and (<i>E</i>)-2-decenal, the nanosensors\ndemonstrated distinct responses, with PANI/GO exhibiting higher sensitivity.\nThe resonance frequency shifts correlated with the concentration of\nthe compounds, underscoring the potential of these sensors in detecting\nlow concentrations with limits of detection (LOD) and quantification\n(LOQ) lower than 0.44 and 1.15 ng/mL, respectively. Real environment\ntesting with soybean plants indicated that the nanosensors effectively\ndetected semiochemicals emitted by N. viridula adults, especially in the presence of male–female couples,\nunderscoring their potential for agricultural pest monitoring. The\nfindings support the use of these nanosensors for the early detection\nof pest activity, offering a proactive approach to integrated pest\nmanagement.