Oh Sunjong, Baek Nam Seob, Jung Sang-Don, Chung Myung-Ae, Hung Tran Quang, Anandakumar S, Rani V Sudha, Jeong Jong-Ryul, Kim CheolGi
Department of Materials Science and Engineering, Chungnam National University, Daejeon 305-764, Korea
J Nanosci Nanotechnol. 2011 May;11(5):4452-6. doi: 10.1166/jnn.2011.3686.
We have developed a novel platform for selective binding of magnetic labels on planar Hall resistance sensor (PHR) for biosensing applications. The photoresist (PR) micro wells were prepared on the PHR sensor junctions to trap the magnetic bead at specified locations on the sensor surface and thin layer of Au was sputtered in the PR wells immobilize bimolecular. The Au surface is functionalized with single-stranded oligonucleotide and further biotin was used to immobilize streptavidin coated magnetic labels (Dynabeads Myone 1.0 microm, Invitrogen Co.). After removal of the PR wells on the sensor surface the non specific binding magnetic labels were successfully removed and only the chemically bounded magnetic labels were remained on the Au surface for detection of biomolecules using PHR sensor. We controlled the number of magnetic labels on the PHR sensor surface by using different sizes of the PR well on the junctions. The specifically bounded magnetic labels were successfully detected by characterizing the individual PHR sensor junctions. This technique enables the complete control over the magnetic labels for selective binding of biomolecules on the sensor surface for increasing the sensitivity of the PHR sensor as well as removal of the non specific bindings on the sensor surface.
我们开发了一种新型平台，用于在平面霍尔电阻传感器（PHR）上选择性结合磁性标签，以用于生物传感应用。在PHR传感器结上制备光刻胶（PR）微孔，将磁珠捕获在传感器表面的指定位置，并在PR孔中溅射金薄层以固定双分子。金表面用单链寡核苷酸进行功能化，然后进一步使用生物素固定链霉亲和素包被的磁性标签（Invitrogen公司的Dynabeads Myone 1.0微米磁珠）。去除传感器表面的PR孔后，成功去除了非特异性结合的磁性标签，仅化学结合的磁性标签留在金表面，用于使用PHR传感器检测生物分子。我们通过在结上使用不同尺寸的PR孔来控制PHR传感器表面上磁性标签的数量。通过对各个PHR传感器结进行表征，成功检测到了特异性结合的磁性标签。该技术能够完全控制磁性标签，以实现生物分子在传感器表面的选择性结合，从而提高PHR传感器的灵敏度，并去除传感器表面的非特异性结合。
