Department of Micro- and Nanotechnology, Technical University of Denmark, DTU Nanotech, Building 345B, DK-2800 Kongens Lyngby, Denmark.
Biosens Bioelectron. 2013 Feb 15;40(1):147-52. doi: 10.1016/j.bios.2012.07.002. Epub 2012 Jul 20.
We compare measurements of the Brownian relaxation response of magnetic nanobeads in suspension using planar Hall effect sensors of cross geometry and a newly proposed bridge geometry. We find that the bridge sensor yields six times as large signals as the cross sensor, which results in a more accurate determination of the hydrodynamic size of the magnetic nanobeads. Finally, the bridge sensor has successfully been used to measure the change in dynamic magnetic response when rolling circle amplified DNA molecules are bound to the magnetic nanobeads. The change is validated by measurements performed in a commercial AC susceptometer. The presented bridge sensor is, thus, a promising component in future lab-on-a-chip biosensors for detection of clinically relevant analytes, including bacterial genomic DNA and proteins.
我们比较了使用交叉几何形状的平面霍尔效应传感器和新提出的桥接几何形状对悬浮中的磁性纳米球的布朗松弛响应的测量。我们发现，桥接传感器产生的信号是交叉传感器的六倍，这使得更准确地确定磁性纳米球的流体动力学尺寸成为可能。最后，桥接传感器成功地用于测量当滚环扩增的 DNA 分子与磁性纳米球结合时动态磁响应的变化。通过在商业交流磁化率计中进行的测量来验证该变化。因此，所提出的桥接传感器是未来用于检测临床相关分析物（包括细菌基因组 DNA 和蛋白质）的片上实验室生物传感器中的有前途的组件。
