基于上转换适配体荧光纳米材料特异性检测磺胺二甲氧嘧啶的方法研究  

Study on Specific Detection of Sulfadimethoxine Based on Aptamer-Modified Up-Conversion Fluorescent Nanomaterial

作　　者：范丹阳 张学成 高俊 王家斌[2] 吕海霞[1] FAN Dan-yang;ZHANG Xue-cheng;GAO Jun;WANG Jia-bin;Lü Hai-xia(College of Materials Science and Engineering,Fuzhou University,Fuzhou 350108,China;College of Biological Science and Engineering,Fuzhou University,Fuzhou 350108,China)

机构地区：[1]福州大学材料科学与工程学院,福建福州350108 [2]福州大学生物科学与工程学院,福建福州350108

出　　处：《光谱学与光谱分析》2022年第11期3409-3414,共6页Spectroscopy and Spectral Analysis

基　　金：国家自然科学基金面上项目(31771893);福建省科学计划引导项目(2019Y0003)资助。

摘　　要：上转换纳米粒子(UCNPs)因其具有强生物穿透性、大斯托克位移、良好的光稳定性和生物相容性等优点而被广泛应用于生物医药分析领域。通过聚丙烯酸(PAA)对油酸(OA)配体的上转换纳米粒子(OA-UCNPs)进行表面改性得到亲水性纳米粒子PAA-UCNPs,再通过酰胺化反应将适配体(Apt)共价偶联到PAA-UCNPs表面得到Apt-UCNPs并将其作为能量供体,以黑洞猝灭剂(BHQ1)作为能量受体,构建了一种基于荧光共振能量转移特异性检测磺胺二甲氧嘧啶(SDM)的方法。通过红外光谱(FTIR)及扫描电镜(SEM)对OA-UCNPs、PAA以及PAA-UCNPs的结构和性能进行了表征。从红外光谱中可以看出,相比较于OA-UCNPs,PAA-UCNPs于1722 cm^(-1)处出现了新峰,可能为PAA的—C—O伸缩振动峰,且在3400 cm^(-1)附近存在的宽带可能归因于PAA中O—H伸缩振动;从扫描电镜实验结果可以看出,PAA修饰前分散在环己烷中的OA-UCNPs尺寸约为31 nm,而PAA修饰后分散在水溶液中的UCNPs直径约为49 nm。分析认为长链的PAA分子体积比油酸分子大,因此包覆在UCNPs表面会使其尺寸增加,以上结果均表明PAA可能已被修饰到UCNPs表面。通过紫外可见光谱对Apt-UCNPs、Apt及PAA-UCNPs的结构进行了表征。结果发现相对于PAA-UCNPs,Apt-UCNPs的紫外吸收光谱在260 nm处出现了较明显的Apt特征吸收峰,这表明适配体可能已被修饰到UCNPs表面。对Apt-UCNPs用于检测SDM的机理进行了初步探讨,结果发现Apt-UCNPs在540 nm的发射峰与BHQ1的吸收峰发生重叠,表明Apt-UCNPs上的能量可通过共振能量转移效应转移到BHQ1使得Apt-UCNPs的荧光被猝灭。对猝灭剂BHQ1的浓度进行了优化,结果表明当BHQ1浓度为15μmol·L^(-1)时,荧光猝灭效率为55%。在最佳实验条件下,相对荧光强度与SDM浓度(150~1000 ng·mL^(-1))之间具有良好的线性关系,选取与SDM结构相似的磺胺吡啶和磺胺醋酰作对照实验,发现尽管磺胺吡啶和磺胺醋酰的浓度Due to the strong biological penetration,large stoke shift,good photostability and biocompatibility,up-conversion nanoparticles(UCNPs)were widely used in biomedical analysis.In this study,OA-UCNPs,which are UCNPs with oleic acid(OA)as ligand,were modified by polyacrylic acid(PAA)in order to prepare hydrophilic nanoparticles PAA-UCNPs,and then aptamers(Apt)were covalently coupled to the surface of PAA-UCNPs by amidation reaction to obtain Apt-UCNPs.A method for specific detection of sulfadimethoxine(SDM)was constructed by using Apt-UCNPs as energy donors and black hole quencher(BHQ1)as an energy acceptor fluorescence resonance energy transfer.The structure and performance of UCNPs,PAA and PAA-UCNPs were characterized by infrared spectroscopy(FTIR)and scanning electron microscope(SEM).The results of FTIRshowed that compared with UCNPs,PAA-UCNPs appeared at a new peak at 1722 cm^(-1) which was attributed to the C O stretching vibration peak of PAA,and the wide band around 3400 cm^(-1) attributed to the O—H stretching vibration of PAA;the results of the SEM test indicated that the size of UCNPs and PAA-UCNPs was 31 and 49 nm,respectively.It may be because the molecular volume of long-chain PAA is larger than that of oleic acid,so coating on the surface of UCNPs will increase its size,and the above results indicated PAA may have had been modified to the surface of UCNPs.The structure and properties of Apt-UCNPs,Apt and PAA-UCNPs,were characterized by ultraviolet-visible spectroscopy.It was found that compared with PAA-UCNPs,Apt-UCNPs had a more obvious Apt characteristic absorption peak at 260 nm,which showed that the aptamer could have been modified to the surface of UCNPs.In addition,the mechanism of using Apt-UCNPs to detect SDM was also discussed.The results showed that the emission peak of Apt-UCNPs at 540 nm overlapped with the absorption peak of BHQ1,which indicated that the energy on Apt-UCNPs can be transferred to BHQ1 through the fluorescence resonance energy transfer effect so that the fluorescence of Apt

关 键 词：上转换纳米粒子 磺胺二甲氧嘧啶 适配体 

分 类 号：O657.3[理学—分析化学]