Fluorescence resonance energy transfer biosensor between upconverting nanoparticles and palladium nanoparticles for ultrasensitive CEA detection
Fluorescence resonance energy transfer biosensor between upconverting nanoparticles and palladium nanoparticles for ultrasensitive CEA detection
复制标题
上转换纳米颗粒和钯纳米颗粒之间的荧光共振能量转移生物传感器，用于超灵敏 CEA 检测
DOI：
10.1016/j.bios.2016.07.070
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发表时间：
2016-12-15
影响因子：
12.6
通讯作者：
Liu, Zhihong
中科院分区：
文献类型：
--
作者：
Li, Hui;Shi, Liang;Liu, Zhihong
基于上转换纳米粒子（UCPs）与钯纳米粒子（PdNPs）之间的荧光共振能量转移（FRET），构建了一种超灵敏的癌胚抗原（CEA）生物传感器。通过将Na 2 PdCl 4溶液加入到作为还原剂的N2 H4中心点H2O和作为稳定剂的11-巯基十一烷酸（MUDA）的混合物中来合成PdNPs。通过EDC-NHS偶联方案将CEA适体（5 '-NH 2-ATACCAGCTFATTCAATT-3'）缀合至己二酸（HDA）修饰的UCP（HDA-UCP）。CEA适体的氮官能团与PdNPs之间的配位相互作用使UCPs和PdNPs紧密接近，这导致UCPs的荧光猝灭达到85%的程度。PdNPs对HDA-UCPs的非特异性荧光猝灭可以忽略不计。将CEA引入UCPs-CEA适体-PdNPs荧光猝灭体系后，CEA适体优先与CEA结合，并伴随构象变化，减弱了CEA适体与PdNPs之间的配位作用。结果表明，在2 ~ 100 pg/mL范围内，CEA浓度与UCPs的荧光回收率呈良好的线性关系，检测限为0.8 pg/mL。在稀释的人血清中，CEA的线性范围为4 ~ 100 pg/mL，检出限为1.7 pg/mL。该生物传感器充分利用了PdNPs对UCPs的高猝灭能力，且对非特异性荧光的猝灭可以忽略不计，在生物化学领域具有广阔的应用前景。(C)© 2016 Elsevier B. V.版权所有。
An ultrasensitive biosensor for carcinoembryonic antigen (CEA) was constructed based on fluorescence resonance energy transfer (FRET) between upconverting nanoparticles (UCPs) and palladium nano particles (PdNPs). PdNPs was synthesized by the addition of a solution of Na2PdCl4 into a mixture of N2H4 center dot H2O as the reducing agent and 11-mercaptoundecanoic acid (MUDA) as the stabilizer. The CEA aptamer (5'-NH2-ATACCAGCTFATTCAATT-3') was conjugated to hexanedioic acid (HDA) modified UCPs (HDA-UCPs) through an EDC-NHS coupling protocol. The coordination interaction between nitrogen functional groups of the CEA aptamer and PdNPs brought UCPs and PdNPs in close proximity, which resulted in the fluorescence quenching of UCPs to an extent of 85%. And the non-specific fluorescence quenching caused by PdNPs towards HDA-UCPs was negligible. After the introduction of CEA into the UCPs-CEA aptamer-PdNPs fluorescence quenching system, the CEA aptamer preferentially combined with CEA accompanied by the conformational change which weakened the coordination interaction between the CEA aptamer and PdNPs. So fluorescence recovery of UCPs was observed and a linear relationship between the fluorescence recovery of UCPs and the concentration of CEA was obtained in the range from 2 pg/mL to 100 pg/mL in the aqueous buffer with the detection limit of 0.8 pg/mL. The ultrasensitive detection of CEA was also realized in diluted human serum with a linear range from 4 pg/mL to 100 pg/mL and a detection limit of 1.7 pg/mL. This biosensor makes the most of the high quenching ability of PdNPs towards UCPs with negligible non-specific fluorescence quenching and has broad application prospects in biochemistry. (C) 2016 Elsevier B.V. All rights reserved.