Bukhamsin Abdullah H, Shetty Saptami S, Fakeih Esraa, Martinez Mario Soto, Lerma Cecilia, Mundummal Mufeeda, Wang Jian You, Kosel Jürgen, Al-Babili Salim, Blilou Ikram, Salama Khaled N
Bioengineering, Biological and Environmental Science and Engineering (BESE) Division, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia.
Center of Excellence - Sustainable Food Security, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia.
Sci Adv. 2025 Apr 18;11(16):eads8733. doi: 10.1126/sciadv.ads8733.
Specific phytohormone combinations regulate plant growth and responses to environmental stimuli. Monitoring their distribution is key for understanding signaling cross-talk and detecting plant stress early. However, typical means of monitoring these chemicals are often laborious, destructive, or limited to model plants. In this study, we present an amperometric and minimally invasive sensing platform that can be attached to plant leaves for the simultaneous detection of two key phytohormones, auxin [indole-3-acetic acid (IAA)] and salicylic acid (SA). The platform incorporates magnetized microneedles coated with superparamagnetic FeO intercalated into a scaffold of multiwalled carbon nanotubes (MWCNTs). It achieves detection limits of 1.41 μM (IAA) and 1.15 μM (SA) with a strong correlation ( ≥ 0.7) to ultrahigh-performance liquid chromatography-tandem mass spectrometry measurements. Furthermore, implementing cyclical amperometric cleaning extends the sensor lifespan by preventing electrode passivation. Last, the sensor's capability to monitor the real-time plant responses to several stressors is validated, showcasing its potential for phytodiagnostics and precision farming.
特定的植物激素组合调节植物生长并影响其对环境刺激的反应。监测它们的分布是理解信号交互作用和早期检测植物胁迫的关键。然而，监测这些化学物质的典型方法通常费力、具有破坏性或仅限于模式植物。在本研究中，我们展示了一种电流型微创传感平台，该平台可附着于植物叶片，用于同时检测两种关键植物激素，生长素[吲哚-3-乙酸（IAA）]和水杨酸（SA）。该平台包含涂有超顺磁性FeO的磁化微针，这些微针插在多壁碳纳米管（MWCNT）支架中。它实现了1.41 μM（IAA）和1.15 μM（SA）的检测限，与超高效液相色谱-串联质谱测量具有很强的相关性（≥0.7）。此外，通过实施周期性电流清洗可防止电极钝化，从而延长传感器寿命。最后，验证了该传感器监测植物对多种胁迫源实时反应的能力，展示了其在植物诊断和精准农业中的潜力。
