Hu Ye, Wang Xiaodong, Wang Cheng, Hou Peichen, Dong Hongtu, Luo Bin, Li Aixue
Beijing Research Center of Intelligent Equipment for Agriculture, Beijing Academy of Agriculture and Forestry Sciences Beijing 100097 China
School of Chemical Sciences, University of Chinese Academy of Sciences 19A YuQuan Road Beijing 100049 China.
RSC Adv. 2020 Jan 17;10(6):3115-3121. doi: 10.1039/c9ra09951d. eCollection 2020 Jan 16.
Indole-3-acetic acid (IAA) and salicylic acid (SA) are two important phytohormones. In this work, for the first time, a ratiometric electrochemical sensor was developed for quantifying IAA and SA simultaneously. A composite of multi wall carbon nanotubes (MWNT) and carbon black (CB) was used to enhance the sensitivity of electrochemical detection. Ferrocene (Fc) was used as the reference molecule to offer a built-in correction to improve the accuracy. A good linearity was constructed between the / and the concentration of IAA from 25 μM to 1000 μM. The linear equation was = 0.00159 + 0.124 ( = 0.9887). The LOD for IAA was 1.99 μM. Meanwhile, the / gradually increased with increasing concentration of SA. The linear regression equation for SA was = 0.00107 + 0.34465 ( = 0.9488) with the LOD of 3.30 μM. Thus, the as-prepared multifunctional ratiometric electrochemical sensor was successfully applied to detect IAA and SA at the same time. This sensor was also successfully used to detect IAA and SA in the homogenates of soybean seedlings under salt stress, confirming the practical applicability of the sensor. And the obtained results agreed well with those obtained by the ultra performance liquid chromatography-mass spectrometry (UPLC-MS) method.
吲哚 - 3 - 乙酸（IAA）和水杨酸（SA）是两种重要的植物激素。在本研究中，首次开发了一种用于同时定量检测IAA和SA的比率型电化学传感器。采用多壁碳纳米管（MWNT）和炭黑（CB）的复合材料来提高电化学检测的灵敏度。二茂铁（Fc）用作参比分子以提供内置校正，从而提高准确性。在IAA浓度为25 μM至1000 μM之间，构建了 / 与IAA浓度之间的良好线性关系。线性方程为 = 0.00159 + 0.124（ = 0.9887）。IAA的检测限为1.99 μM。同时， / 随着SA浓度的增加而逐渐增大。SA的线性回归方程为 = 0.00107 + 0.34465（ = 0.9488），检测限为3.30 μM。因此，所制备的多功能比率型电化学传感器成功地应用于同时检测IAA和SA。该传感器还成功用于检测盐胁迫下大豆幼苗匀浆中的IAA和SA，证实了该传感器的实际适用性。并且所获得的结果与超高效液相色谱 - 质谱联用（UPLC - MS）方法所获得的结果吻合良好。
