Ehresmann Arno, Koch Iris, Holzinger Dennis
Institute of Physics and Center for Interdisciplinary Nanostructure Science and Technology (CINSaT), University of Kassel, Heinrich-Plett-Str.40, Kassel D-34132, Germany.
Sensors (Basel). 2015 Nov 13;15(11):28854-88. doi: 10.3390/s151128854.
A technology platform based on a remotely controlled and stepwise transport of an array arrangement of superparamagnetic beads (SPB) for efficient molecular uptake, delivery and accumulation in the context of highly specific and sensitive analyte molecule detection for the application in lab-on-a-chip devices is presented. The near-surface transport of SPBs is realized via the dynamic transformation of the SPBs' magnetic potential energy landscape above a magnetically stripe patterned Exchange-Bias (EB) thin film layer systems due to the application of sub-mT external magnetic field pulses. In this concept, the SPB velocity is dramatically influenced by the magnitude and gradient of the magnetic field landscape (MFL) above the magnetically stripe patterned EB substrate, the SPB to substrate distance, the magnetic properties of both the SPBs and the EB layer system, respectively, as well as by the properties of the external magnetic field pulses and the surrounding fluid. The focus of this review is laid on the specific MFL design in EB layer systems via light-ion bombardment induced magnetic patterning (IBMP). A numerical approach is introduced for the theoretical description of the MFL in comparison to experimental characterization via scanning Hall probe microscopy. The SPB transport mechanism will be outlined in terms of the dynamic interplay between the EB substrate's MFL and the pulse scheme of the external magnetic field.
本文介绍了一种基于超顺磁珠（SPB）阵列排列的远程控制和逐步传输的技术平台，用于在芯片实验室设备中进行高特异性和灵敏的分析物分子检测时实现高效的分子摄取、递送和积累。通过在磁条图案化的交换偏置（EB）薄膜层系统上方施加亚毫特斯拉外部磁场脉冲，实现了SPB在近表面的传输，这是由于SPB的磁势能景观发生了动态变化。在这一概念中，SPB的速度受到磁条图案化EB基板上方磁场景观（MFL）的大小和梯度、SPB与基板的距离、SPB和EB层系统的磁性能，以及外部磁场脉冲和周围流体的性质的显著影响。本综述的重点是通过轻离子轰击诱导磁图案化（IBMP）在EB层系统中进行特定的MFL设计。与通过扫描霍尔探针显微镜进行的实验表征相比，引入了一种数值方法来对MFL进行理论描述。将根据EB基板的MFL与外部磁场脉冲方案之间的动态相互作用来概述SPB的传输机制。
