Quantification of rolling circle amplified DNA using magnetic nanobeads and a Blu-ray optical pick-up unit
Quantification of rolling circle amplified DNA using magnetic nanobeads and a Blu-ray optical pick-up unit
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DOI：
10.1016/j.bios.2014.09.097
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发表时间：
2015-05-15
影响因子：
12.6
通讯作者：
Hansen, Mikkel Fougt
中科院分区：
文献类型：
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作者：
Donolato, Marco;Antunes, Paula;Hansen, Mikkel Fougt
我们提出的第一个实现的蓝光光学拾取单元（OPU）的高性能低成本读出的均匀的测定在一个多室的微流体盘与室厚度为600 μ m。该测定依赖于磁性纳米珠在沿着光传播方向施加的振荡磁场中的动力学的光学测量。OPU提供的激光通过样品室传输，并通过反射镜反射回OPU的光电探测器阵列。第二谐波光电检测器信号的光谱与所施加磁场的频率的关系显示出由于自由旋转的磁性纳米珠而导致的特征峰。通过挂锁探针识别和滚环扩增形成的芯片外DNA的类似于1 μ m螺旋的结合珠显示出不同的动力学，特征峰的强度降低。我们确定了最佳磁珠浓度为0.1 mg/mL，并测量了响应与由大肠杆菌形成的DNA螺旋浓度的关系。我们已经发现了10 pM的检测限和约两个数量级的动态范围，这是使用昂贵和笨重的实验室设备获得的性能相媲美。该设备利用先进但低成本的蓝光OPU技术，提供低成本和高性能的基于磁珠的均相生物测定读数。该设备是高度灵活的，我们已经证明了其使用的微流体室在一个磁盘上的厚度与目前的光学介质大规模生产设施兼容。(C)2014爱思唯尔有限公司版权所有。
We present the first implementation of a Blu-ray optical pickup unit (OPU) for the high-performance low-cost readout of a homogeneous assay in a multichamber microfluidic disc with a chamber thickness of 600 mu m. The assay relies on optical measurements of the dynamics of magnetic nanobeads in an oscillating magnetic field applied along the light propagation direction. The laser light provided by the OPU is transmitted through the sample chamber and reflected back onto the photo detector array of the OPU via a mirror. Spectra of the 2nd harmonic photo detector signal vs. the frequency of the applied magnetic field show a characteristic peak due to freely rotating magnetic nanobeads. Beads bound to similar to 1 mu m coils of DNA formed off-chip by padlock probe recognition and rolling circle amplification show a different dynamics and the intensity of the characteristic peak decreases. We have determined the optimum magnetic bead concentration to 0.1 mg/mL and have measured the response vs. concentration of DNA coils formed from Escherichia Coil. We have found a limit of detection of 10 pM and a dynamic range of about two orders of magnitude, which is comparable to the performance obtained using costly and bulky laboratory equipment. The presented device leverages on the advanced but low-cost technology of Blu-ray OPUs to provide a low-cost and high-performance magnetic bead-based readout of homogeneous bioassays. The device is highly flexible and we have demonstrated its use on microfluidic chambers in a disc with a thickness compatible with current optical media mass-production facilities. (C) 2014 Elsevier B.V. All rights reserved.