SERS-Enabled Sensitive Detection of Plant Volatile Biomarker Methyl Salicylate
Song Chen, Yongchen Wang, Yu Lei, Jing Zhao
Abstract
Volatile organic compounds (VOCs) contain unique information about infection of plants; thus, they can be used as reliable biomarkers for plant diseases. Among various VOCs, methyl salicylate (MeSA) is released abundantly during pathogenic infections because MeSA is emitted not only at the infected site but also throughout the whole plant as a systemic response. In this work, 4-mercaptophenylboronic acid (MPBA) functionalized Au nanoparticles were employed as a probe for MeSA vapor sensing via surface-enhanced Raman scattering (SERS) spectroscopy. The SERS sensors can detect MeSA as low as 0.608 ppb (S/N of 3) with excellent intra- and interassay reproducibility. The origin of Raman signal change was attributed to the weak, reversible intermolecular interaction between MPBA and MeSA. This study demonstrates that the SERS sensing platform holds great promise in noninvasive and fast monitoring of volatile biomarkers for crop health.