摘要
镁离子(Mg^(2+))是植物光合、呼吸及遗传物质合成等重要生理过程的必需营养元素,准确检测无土栽培营养液中Mg^(2+)含量对作物生产调控具有重要意义。Mg^(2+)荧光探针材料合成复杂且易受钙离子(Ca^(2+))、锌离子(Zn^(2+))干扰。本研究采用水杨醛荧光探针开展了营养液Mg^(2+)检测,系统测定了该分子探针的灵敏性、选择性、抗干扰性,并通过加标回收率结果证明了水杨醛荧光探针测定的重复性。试验结果表明:在Mg^(2+)浓度0~800μmol/L范围内,水杨醛探针荧光响应强度线性良好,决定系数达到0.999,响应时间约为2 min,可实现对溶液中Mg^(2+)的快速测定;探针对Mg^(2+)的选择性良好,等浓度Ca^(2+)、Zn^(2+)荧光响应强度同比增长系数仅为Mg^(2+)强度的2.5%、9.1%。同时,探针具有较好的抗干扰性,Ca^(2+)、Zn^(2+)与Mg^(2+)等量共存,较单一Mg^(2+)溶液水杨醛荧光探针测定荧光强度同比增长系数在-0.004~0.009之间,上下波动小于0.01。Ba^(2+)、Cu^(2+)、Mn^(2+)、Fe ^(2+ )、Fe ^(3+)对水杨醛探针存在荧光猝灭影响;实际样本的加标回收率为99%~104.9%,较离子色谱法测定结果的相对误差不大于1.33%,RMSE为5.78 mol/L。本研究初步验证了水杨醛荧光探针用于营养液Mg^(2+)检测的可行性。
With the continuous development of soilless cultivation technology in China,the testing of the internal components of hydroponic nutrient solutions,which are a key part of soilless cultivation technology,has become a hot topic of research.Magnesium ions(Mg^(2+))are essential nutrients for important physiological processes such as photosynthesis,respiration,and the synthesis of genetic material in plants,so the accurate detection of Mg^(2+)content in soilless nutrient solutions is of key significance for the regulation of crop production.A summary of the available literature showed that Mg^(2+)detection had evolved from traditional atomic absorption to current fluorescent probe detection techniques,but Mg^(2+)fluorescent probe materials were complex to synthesize and were susceptible to interference from calcium(Ca^(2+))and zinc(Zn^(2+)).Salicylaldehyde,a readily available and inexpensive intermediate for commercial fine chemical synthesis,can be combined with Mg^(2+)to form a stable chelate for Mg^(2+)detection.A salicylaldehyde fluorescent probe combined with a microfiber optic spectrometer was used for the detection of Mg^(2+)in nutrient solutions to investigate the detection mechanism.The sensitivity,selectivity,and interference resistance of the molecular probe were systematically determined,and the reproducibility of the salicylaldehyde fluorescent probe was investigated through the measurement and spiked recovery of strawberry nutrient solutions.Experimental results showed that the fluorescent probe binded to the magnesium ion to form a stable complex,producing chelated fluorescence enhancement.The fluorescence response intensity of the salicylaldehyde probe was well linear in the concentration range of 0~800μmol/L Mg^(2+),with a correlation coefficient of 0.999 and a response time of about 2 min,enabling the rapid determination of Mg^(2+)in solution.The probe showed good selectivity for Mg^(2+),with the fluorescence response intensity of equal concentrations of Ca^(2+)and Zn^(2+)ions increasing by only 2.5%and 9.1%of the Mg^(2+)intensity year-on-year,with a weak fluorescence enhancement compared to the blank group.At the same time,the probe had good resistance to interference,and the fluorescence intensity measured by solutions of Mg^(2+)coexisting with Ca^(2+)and Zn^(2+)coexisting with Mg^(2+)in equal amounts had a year-on-year growth rate between-0.004 and 0.009 compared with the fluorescence intensity measured by a single Mg^(2+)solution salicylaldehyde fluorescent probe,with the growth rate fluctuating up and down by less than 0.01.The five solutions of Ba^(2+),Cu^(2+),Mn^(2+),Fe^(2+),and Fe^(3+) showed fluorescence intensity growth rates ranging from-0.21 to-0.91 year-on-year,with a fluorescence burst compared with the pure water blank group.The spiked recoveries of the actual samples ranged from 99%to 104.9%with a relative error of less than 1.33%and an RMSE of 5.78μmol/L,demonstrating the good sensitivity and reproducibility of the salicylaldehyde fluorescent molecular probe for the determination of Mg^(2+)concentrations in nutrient solutions.In conclusion,the research result initially validated the feasibility of salicylaldehyde fluorescent probes for Mg^(2+)detection in nutrient solutions.
作者
阳清亮
李浩榛
刘刚
张淼
YANG Qingliang;LI Haozhen;LIU Gang;ZHANG Miao(Key Laboratory on Modern Precision Agriculture System Integration Research,Ministry of Education,China Agricultural University,Beijing 100083,China;Key Laboratory of Agricultural Information Acquisition Technology,Ministry of Agriculture and Rural Affairs,China Agricultural University,Beijing 100083,China)
出处
《农业机械学报》
EI
CAS
CSCD
北大核心
2021年第S01期344-350,共7页
Transactions of the Chinese Society for Agricultural Machinery
基金
浙江省重点研发计划项目(2020C02017)
云南省院士工作站项目(LJ-2018001)
中央高校基本科研业务费项目(2021TC031)
关键词
无土栽培
营养液
水杨醛荧光探针
镁离子
回收率
soilless culture
nutrient solution
salicylaldehyde fluorescent probe
magnesium ions
recovery rate
