Integrated dual-modality microfluidic sensor for biomarker detection using lithographic plasmonic crystal
Integrated dual-modality microfluidic sensor for biomarker detection using lithographic plasmonic crystal
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DOI：
10.1039/c7lc01211j
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发表时间：
2018-03-07
期刊：
影响因子：
6.1
通讯作者：
Dong, Liang
中科院分区：
文献类型：
--
作者：
Ali, Md. Azahar;Tabassum, Shawana;Dong, Liang
本文报道了一种集成的双模式微流控传感器芯片，该芯片由镀金(Au)和氧化石墨烯(GO)的周期性纳米孔图案化阵列组成，用于在有限的样品体积中检测目标生物标志物分子。该设备从Au-Go纳米孔的单个感测区域产生电化学和表面等离子体共振(SPR)信号。Au-GO纳米孔被特定的受体分子功能化，作为空间上定义良好的纳米结构的工作电极用于电化学传感，以及通过表面等离子体激元的激发作为纳米结构的等离子体晶体用于基于SPR的传感。电化学测量的高灵敏度源于工作电极表面纳米孔的存在，在那里发生了氧化还原物种的径向扩散。作为补充，SPR检测允许方便地跟踪动态的抗原-抗体相互作用，以描述发生在传感器表面的结合和解离阶段。软性光刻形成的纳米孔提供了传感器对表皮生长因子受体(ErbB2)分子的高度重复性，即使在毫微摩尔水平也是如此。电化学测量对ErbB_2的灵敏度在1个FM到0.1个微米的范围内为20.47微米微米-1厘米-2，SPR测量的灵敏度在10到1毫微米的范围内为1.35 nm微米-1，在1毫微米到0.1微米的范围内为0.80 nm微米-1。集成的双模式传感器提供了更高的灵敏度(通过用于电化学测量的更高的表面积和从纳米孔扩散)，以及抗原-抗体结合的动态测量(通过SPR测量)，同时使用相同的采样体积在相同的感测区域中同时操作。
This paper reports an integrated dual-modality microfluidic sensor chip, consisting of a patterned periodic array of nanoposts coated with gold (Au) and graphene oxide (GO), to detect target biomarker molecules in a limited sample volume. The device generates both electrochemical and surface plasmon resonance (SPR) signals from a single sensing area of Au-GO nanoposts. The Au-GO nanoposts are functionalized with specific receptor molecules, serving as a spatially well-defined nanostructured working electrode for electrochemical sensing, as well as a nanostructured plasmonic crystal for SPR-based sensing via the excitation of surface plasmon polaritons. High sensitivity of the electrochemical measurement originates from the presence of the nanoposts on the surface of the working electrode where radial diffusion of redox species occurs. Complementarily, the SPR detection allows convenient tracking of dynamic antigen-antibody interactions, to describe the association and dissociation phases occurring at the sensor surface. The softlithographically formed nanoposts provide high reproducibility of the sensor response to epidermal growth factor receptor (ErbB2) molecules even at a femtomolar level. Sensitivities of the electrochemical measurements to ErbB2 are found to be 20.47 mu A mu M-1 cm-2 in a range from 1 fM to 0.1 mu M, and those of the SPR measurements to be 1.35 nm mu M-1 in a range from 10 pM to 1 nM, and 0.80 nm mu M-1 in a range from 1 nM to 0.1 mu M. The integrated dual-modality sensor offers higher sensitivity (through higher surface area and diffusions from nanoposts for electrochemical measurements), as well as the dynamic measurements of antigen-antibody bindings (through the SPR measurement), while operating simultaneously in a same sensing area using the same sample volume.