Development of a mass-producible on-chip plasmonic nanohole array biosensor
Development of a mass-producible on-chip plasmonic nanohole array biosensor
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DOI：
10.1039/c1nr10883b
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发表时间：
2011-01-01
期刊：
影响因子：
6.7
通讯作者：
Nishida, Munehiro
中科院分区：
文献类型：
--
作者：
Nakamoto, Kohei;Kurita, Ryoji;Nishida, Munehiro
我们开发了一种基于聚合物薄膜的等离子体装置，其光学特性经过调整用于测量生物样品。该器件具有使用紫外固化聚合物通过纳米压印技术制造的圆形纳米孔阵列结构，然后通过电子束沉积沉积金薄膜。因此，该设备具有可批量生产性，这对于生物亲和传感器来说也非常重要。首先，优化金膜厚度和孔深度以获得反射光谱的最大倾角位移。倾角位移相当于等离子体器件表面对折射率变化的敏感度。我们还利用时域有限差分法计算了改变上述条件后反射光谱的变化，得到了理论曲线与实验曲线的吻合。将纳米孔周期从400 nm调整至900 nm，使得可以在可见光波长区域进行测量，以测量光吸收较小的水样。调整后的底部填充金纳米孔阵列被整合到微流体装置中，该装置覆盖有基于 PDMS 的微通道，该微通道宽 2 毫米，深 20 毫米。作为概念验证，该装置通过在等离子体阵列上进行直接免疫化学反应来检测TNF-α，并通过胶体金标记扩增而不是酶促扩增获得了21 ng mL(-1)的检测限。
We have developed a polymer film based plasmonic device whose optical properties are tuned for measuring biological samples. The device has a circular nanohole array structure fabricated with a nanoimprint technique using a UV curable polymer, and then gold thin film is deposited by electron beam deposition. Therefore, the device is mass-producible, which is also very important for bioaffinity sensors. First the gold film thickness and hole depth were optimized to obtain the maximum dip shift for the reflection spectra. The dip shift is equivalent to the sensitivity to refractive index changes at the plasmonic device surface. We also calculated the variation in reflection spectra by changing the above conditions using the finite-difference time domain method, and we obtained agreement between the theoretical and experimental curves. The nanohole periodicity was adjusted from 400 to 900 nm to make it possible to perform measurements in the visible wavelength region to measure the aqueous samples with less optical absorption. The tuned bottom filled gold nanohole array was incorporated in a microfluidic device covered with a PDMS based microchannel that was 2 mm wide and 20 mm deep. As a proof of concept, the device was used to detect TNF-alpha by employing a direct immunochemical reaction on the plasmonic array, and a detection limit of 21 ng mL(-1) was obtained by amplification with colloidal gold labeling instead of enzymatic amplification.