Indole-3-acetic acid (IAA) and salicylic acid (SA), pivotal regulators in plant growth, are integral to a variety of plant physiological activities. The ongoing and simultaneous monitoring of these hormones in vivo enhances our comprehension of their interactive and regulatory roles. Traditional detection methods, such as liquid chromatography-mass spectrometry, cannot obtain precise and immediate information on IAA and SA due to the complexity of sample processing. In contrast, the electrochemical detection method offers high sensitivity, rapid response times, and compactness, making it well-suited for in vivo or real-time detection applications. A microneedle electrochemical sensor system crafted from disposable stainless steel (SS) wire was specifically designed for the real-time assessment of IAA and SA in plant in situ. This sensor system included a SS wire (100 μm diameter) coated with carbon cement and multi-walled carbon nanotubes, a plain platinum wire (100 μm diameter), and an Ag/AgCl wire (100 μm diameter). Differential pulse voltammetry and amperometry were adopted for detecting SA and IAA within the range of 0.1–20 μM, respectively. This sensor was applied to track IAA and SA fluctuations in tomato leaves during DC3000 infection, offering continuous data. Observations indicated an uptick in SA levels following infection, while IAA production was suppressed. The newly developed disposable SS wire-based microneedle electrochemical sensor system is economical, suitable for mass production, and inflicts minimal damage during the monitoring of SA and IAA in plant tissues. This disposable microneedle electrochemical sensor facilitates in vivo detection of IAA and SA in smaller plant tissues and allows for long-time monitoring of their concentrations, which not only propels research into the regulatory and interaction mechanisms of IAA and SA but also furnishes essential tools for advancing precision agriculture.

中文翻译：

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基于一次性不锈钢丝的微针电化学传感器实时分析受Pst DC3000感染的番茄叶片中吲哚-3-乙酸和水杨酸


3-吲哚乙酸 (IAA) 和水杨酸 (SA) 是植物生长的关键调节剂，是多种植物生理活动不可或缺的组成部分。对体内这些激素的持续和同步监测增强了我们对其相互作用和调节作用的理解。传统的检测方法，如液相色谱-质谱联用技术，由于样品处理的复杂性，无法获得准确、即时的IAA和SA信息。相比之下，电化学检测方法具有高灵敏度、快速响应时间和紧凑性，使其非常适合体内或实时检测应用。由一次性不锈钢 (SS) 线制成的微针电化学传感器系统专为在工厂原位实时评估 IAA 和 SA 而设计。该传感器系统包括一根涂有碳水泥和多壁碳纳米管的 SS 线（直径 100 μm）、一根普通铂线（直径 100 μm）和一根 Ag/AgCl 线（直径 100 μm）。采用差分脉冲伏安法和电流法分别检测0.1-20 μM范围内的SA和IAA。该传感器用于跟踪 DC3000 感染期间番茄叶片中 IAA 和 SA 的波动，提供连续数据。观察结果表明，感染后 SA 水平上升，而 IAA 产生受到抑制。新开发的一次性SS线微针电化学传感器系统经济实惠，适合大规模生产，并且在监测植物组织中SA和IAA时造成的损伤最小。 这种一次性微针电化学传感器有助于在较小的植物组织中体内检测 IAA 和 SA，并可以对其浓度进行长期监测，这不仅推动了对 IAA 和 SA 的调节和相互作用机制的研究，而且还为推进 IAA 和 SA 的研究提供了重要工具。精准农业。