荧光共振能量转移上转换适配体探针法检测牛奶中的痕量氯霉素  

Sensitive Detection of Chloramphenicol Based on Fluorescence Resonance Energy System by Upconversion Nanoparticles Aptamer Sensor

作　　者：李琰[1,2] 刘欣欣 LI Yan;LIU Xinxin(College of Chemistry,Nankai University,Tianjin 300071;National Demonstration Center for Experimental Chemistry Education,Nankai University,Tianjin 300071;College of Food Science and Engineering,Shandong Agricultural University,Shandong Tai’an 271018)

机构地区：[1]南开大学化学学院,天津300071 [2]化学国家级实验教学示范中心(南开大学),天津300071 [3]山东农业大学食品科学与工程学院,山东泰安271018

出　　处：《分析科学学报》2024年第3期255-262,共8页Journal of Analytical Science

基　　金：南开大学实验课程教学项目——交叉学科类项目(23NKSYJC02)资助。

摘　　要：本研究合成了亲水性稀土掺杂的上转换荧光纳米颗粒(UCNPs)作为荧光能量的供体,金纳米颗粒(AuNPs)作为荧光能量的受体,基于荧光共振能量转移(FRET)体系,建立了检测痕量氯霉素(CAP)的适配体探针方法。UCNPs在波长980 nm激发下,在波长547 nm处有特征发射光。柠檬酸钠还原法制备的AuNPs在波长519 nm处有吸收峰。UCNPs通过链霉亲和素-生物素放大系统连接CAP适配体,形成荧光供体探针(UCNPs-apt),AuNPs与修饰巯基的CAP互补链连接,形成荧光受体探针(AuNPs-cDNA)。由于适配体和cDNA的碱基互补配对,发生FRET导致UCNPs荧光猝灭,加入CAP后部分荧光恢复。在最优的检测条件下,CAP浓度与荧光恢复值具有良好的线性关系,线性范围为0.01~10 ng/mL,检测限为5 pg/mL。采用本方法对牛奶样品进行加标回收实验,回收率在93.5%~99.4%之间,相对标准偏差为1.18%~2.84%。该方法具有简单、特异性强、灵敏度高、抗荧光背景干扰能力强等特点。In this study,hydrophilic rare earth-doped upconversion nanoparticles(UCNPs)and gold nanoparticles(AuNPs)were used as donors and acceptors of fluorescent energy,respectively.Based on the fluorescence resonance energy transfer(FRET)system,an aptamer sensor to detect chloramphenicol(CAP)was established.The results showed that UCNPs had strong emission at 547 nm under excitation at 980 nm.AuNPs were prepared by the trisodium citrate reduction method and an obvious absorption peak appeared at 519 nm.UCNPs were connected to chloramphenicol aptamers through the streptavidin-biotin amplification system to form fluorescent donor probes(UCNPs-apt),and AuNPs were linked to the sulfhydryl-modified chloramphenicol complementary chains to form fluorescent acceptor probes(AuNPs-cDNA).Due to the complementary base pairing of aptamer and cDNA,the distance between UCNPs-apt and AuNPs-cDNA was narrowed.At this time,the FRET phenomenon resulted in the fluorescence quenching of UCNPs and partial fluorescence recovery after CAP was added.Under the optimal detection conditions,the CAP concentration had a good linear relationship with the fluorescence recovery value.The detection range was 0.01-10 ng/mL,and the detection limit was 5 pg/mL.This method was used to carry out recovery experiments on milk samples.The recovery rate was 93.5%-99.4%,and the relative standard deviation was 1.18%-2.84%.The method indicated simple,highly selective and sensitive,minimal autofluorescence,rather low interference background characteristics.

关 键 词：上转换荧光纳米材料 金纳米颗粒 荧光共振能量转移 氯霉素 适配体 

分 类 号：O657.3[理学—分析化学]