聚乙烯亚胺和Mg2+荧光增敏快速检测四环素类抗生素  

Rapid detection of tetracyclines by polyethyleneimine and Mg 2+-based fluorescence enhancement

作　　者：王安琪[1,2] 钱美汝 王雪 韩建刚[1,2] 李威 李胎花[1,2] WANG Anqi;QIAN Meiru;WANG Xue;HAN Jiangang;LI Wei;LI Taihua(Co-Innovation Center for the Sustainable Forestry in Southern China,College of Ecology and Environment,Nanjing Forestry University,Nanjing 210037,China;National Positioning Observation Station of Hung-tse Lake Wetland Ecosystem,Hongze 223100,China)

机构地区：[1]南京林业大学生态与环境学院,南方现代林业协同创新中心,南京210037 [2]江苏洪泽湖湿地生态系统国家定位观测研究站,洪泽223100

出　　处：《林业工程学报》2024年第4期72-78,共7页Journal of Forestry Engineering

基　　金：江苏省自然科学基金(BK20191387)。

摘　　要：四环素类抗生素(TCs)是一类广谱抗菌药物,被广泛应用于治疗人畜疾病且效果显著,但过度使用TCs造成其在动物性食品中的残留问题会对自然环境和人体健康造成严重的危害。因此,对食品环境中TCs的残留进行快速检测是十分必要的。迄今为止,对TCs在酸性溶液中荧光检测相关的研究报道较少。在弱酸性条件下,TCs属于弱荧光物质,但与富有氨基的阳离子表面活性剂聚乙烯亚胺(PEI)结合时,在370 nm的激发下,在525 nm处产生较强的绿色荧光;当TCs与PEI和二价金属镁离子(Mg^(2+))共存时,TCs的荧光强度被进一步增强。本研究利用PEI和Mg^(2+)在弱酸性条件下对TCs的协同荧光增敏效应,构建了一种快速、简单、高灵敏检测残留TCs的荧光检测法。实验结果表明:在最优检测条件下,该体系对TCs的定量线性检测范围为5 nmol/L~2μmol/L,其中,美他环素(MTC)、四环素(TC)、土霉素(OTC)的相关系数R^(2)分别为0.939,0.997和0.999,检出限(LOD)分别为3.6,2.7和4.8 nmol/L,均远低于中国和欧盟的限量标准。本方法对MTC、TC、OTC表现出很高的特异性,与常见的其他抗生素均不产生干扰。在实际的牛奶检测中,该体系对TCs的加标回收率为91.64%~104.05%,相对标准偏差为1.20%~10.62%。本方法可适用于酸性体系中残留TCs的分析,为水体和食品中残留TCs检测提供了一种新的依据和思路。As a class of broad-spectrum antibacterial drugs,tetracycline antibiotics(TCs)are widely used to treat human and animal diseases with remarkable effects.However,the abuse of TCs may result in their accumulation in food,posing significant risk to both human health and the conservation of natural environments.Therefore,it is nece-ssary to establish a rapid and sensitive analytical method for the detection of TCs residues to improve safety of animal-derived foods.At present,there have been limited studies found on fluorescence detection of TCs in acidic conditions.In this study,based on the synergistic fluorescence sensitization effect of polyethyleneimine(PEI)and magnesium ion(Mg^(2+))on TCs,a novel,rapid,simple,and highly sensitive fluorescence analytical method for the detection of TCs was developed under weakly acidic conditions.Normally,TCs typically manifest as a weakly fluorescent substance in acidic conditions.The green fluorescence intensity of TCs at 525 nm is increased when combined with the cationic surfactant PEI upon an excitation wavelength at 370 nm.Furthermore,the fluorescence intensity of TCs was significantly enhanced at 525 nm in the coexistence of PEI and divalent metal ion(Mg^(2+)),resulting in strongest green fluorescence emission under identical condition.The deprotonation of hydroxyl and carboxyl groups of TCs was facilitated by the amine-rich cationic surfactant PEI through the operation of electrostatic forces.Concurrently,the oxygen atoms of ketone and hydroxyl groups of TCs chelated with Mg^(2+)to form a stable complex.Consequently,under acidic conditions,the complex of TCs,PEI,and Mg^(2+)might be more stable,leading to a significant increase in fluorescence.With the optimal experimental conditions,the results showed that the analytical method had a good linear relationship with the concentration of TCs within the range of 5 nmol/L to 2μmol/L,and the correlation coefficients(R^(2))of metacycline(MTC),tetracycline(TC),and oxytetracycline(OTC)were 0.939,0.997 and 0.999,respectively.The de

关 键 词：四环素类抗生素 荧光增敏法 聚乙烯亚胺 镁离子 酸性条件 

分 类 号：X832[环境科学与工程—环境工程] O657.3[理学—分析化学] TS252.7[理学—化学]