PDF(Pubmed)
Abstract：
Detecting volatile organic compounds (VOCs) emitted from different plant species and their organs can provide valuable information about plant health and environmental factors that affect them. For example, limonene emission can be a biomarker to monitor plant health and detect stress. Traditional methods for VOC detection encounter challenges, prompting the proposal of novel approaches. In this study, we proposed integrating electrospinning, molecular imprinting, and conductive nanofibers to fabricate limonene sensors. In detail, polyvinylpyrrolidone (PVP) and polyacrylic acid (PAA) served here as fiber and cavity formers, respectively, with multiwalled carbon nanotubes (MWCNT) enhancing conductivity. We developed one-step monolithic molecularly imprinted fibers, where S(-)-limonene was the target molecule, using an electrospinning technique. The functional cavities were fixed using the UV curing method, followed by a target molecule washing. This procedure enabled the creation of recognition sites for limonene within the nanofiber matrix, enhancing sensor performance and streamlining manufacturing. Humidity was crucial for sensor working, with optimal conditions at about 50% RH. The sensors rapidly responded to S(-)-limonene, reaching a plateau within 200 s. Enhancing fiber density improved sensor performance, resulting in a lower limit of detection (LOD) of 137 ppb. However, excessive fiber density decreased accessibility to active sites, thus reducing sensitivity. Remarkably, the thinnest mat on the fibrous sensors created provided the highest selectivity to limonene (Selectivity Index: 72%) compared with other VOCs, such as EtOH (used as a solvent in nanofiber development), aromatic compounds (toluene), and two other monoterpenes (α-pinene and linalool) with similar structures. These findings underscored the potential of the proposed integrated approach for selective VOC detection in applications such as precision agriculture and environmental monitoring.
摘要：
检测从不同植物物种及其器官排放的挥发性有机化合物（VOC）可以提供有关植物健康和影响它们的环境因素的有价值的信息。例如,柠檬烯排放可以作为监测植物健康和检测压力的生物标志物。传统的VOC检测方法面临挑战,促使人们提出新的方法。在这项研究中,我们建议整合静电纺丝，分子印迹，和导电纳米纤维制造柠檬烯传感器。详细来说,聚乙烯吡咯烷酮（PVP）和聚丙烯酸（PAA）在这里用作纤维和空腔形成剂，分别,多壁碳纳米管（MWCNT）增强导电性。我们开发了一步整体分子印迹纤维，其中S（-）-柠檬烯是目标分子，使用静电纺丝技术。使用UV固化方法固定功能腔，然后是目标分子洗涤。该程序能够在纳米纤维基质中创建柠檬烯的识别位点，提高传感器性能和简化制造。湿度对传感器工作至关重要，在约50%RH的最佳条件下。传感器对S(-)-柠檬烯反应迅速,在200s内达到平稳状态。增强光纤密度提高了传感器性能，导致检测下限（LOD）为137ppb。然而,过度的纤维密度降低了对活跃位点的可及性，从而降低灵敏度。值得注意的是,与其他VOC相比，所创建的纤维传感器上的最薄垫对柠檬烯的选择性最高（选择性指数：72％），例如EtOH（用作纳米纤维开发中的溶剂），芳香族化合物（甲苯），和其他两种具有相似结构的单萜（α-pine烯和芳樟醇）。这些发现强调了拟议的集成方法在精准农业和环境监测等应用中用于选择性VOC检测的潜力。
