PCB-Based Magnetometer as a Platform for Quantification of Lateral-Flow Assays
PCB-Based Magnetometer as a Platform for Quantification of Lateral-Flow Assays
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DOI：
10.3390/s19245433
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发表时间：
2019-12-02
期刊：
影响因子：
3.9
通讯作者：
Litvinov, Dmitri
中科院分区：
文献类型：
--
作者：
Khodadadi, Mohammad;Chang, Long;Litvinov, Dmitri
这项工作提出了一种新的感应传感器，femtoMag，可以集成与侧流检测（LFA），以提供检测和定量的分子生物标志物的概念验证演示。飞秒磁传感器采用低成本印刷电路板（PCB）技术制造，可通过相对廉价的电子设备进行控制。它允许沿着LFA测试条的长度对超顺磁性纳米颗粒报告物的数量（或量）进行快速高精度定量。它的检测限为10（-10）emu，相当于检测4 ng超顺磁性氧化铁（Fe 3 O 4）纳米颗粒。使用femtoMag通过定量LFA试纸条测试线内免疫捕获的200 nm磁性报告分子（嵌入聚合物基质中的超顺磁性Fe 3 O 4纳米颗粒）的数量来定量hCG妊娠激素。已证明灵敏度为100 pg/mL。在进一步的设计和控制电子改进后，灵敏度预计将优于10 pg/mL。分析表明，平均需要10（9）个hCG分子才能特异性结合测试线中的10（7）个纳米颗粒。当hCG浓度从0.1 ng/mL增加到10 ng/mL时，样品中hCG分子数量与测试线中报告分子数量的比值从20单调增加到500。低成本、易于使用的femtoMag平台提供高灵敏度/高精度的目标分析物定量，并有望将最先进的医疗诊断测试带到护理点。
This work presents a proof-of-concept demonstration of a novel inductive transducer, the femtoMag, that can be integrated with a lateral-flow assay (LFA) to provide detection and quantification of molecular biomarkers. The femtoMag transducer is manufactured using a low-cost printed circuit board (PCB) technology and can be controlled by relatively inexpensive electronics. It allows rapid high-precision quantification of the number (or amount) of superparamagnetic nanoparticle reporters along the length of an LFA test strip. It has a detection limit of 10(-10) emu, which is equivalent to detecting 4 ng of superparamagnetic iron oxide (Fe3O4) nanoparticles. The femtoMag was used to quantify the hCG pregnancy hormone by quantifying the number of 200 nm magnetic reporters (superparamagnetic Fe3O4 nanoparticles embedded into a polymer matrix) immuno-captured within the test line of the LFA strip. A sensitivity of 100 pg/mL has been demonstrated. Upon further design and control electronics improvements, the sensitivity is projected to be better than 10 pg/mL. Analysis suggests that an average of 10(9) hCG molecules are needed to specifically bind 10(7) nanoparticles in the test line. The ratio of the number of hCG molecules in the sample to the number of reporters in the test line increases monotonically from 20 to 500 as the hCG concentration increases from 0.1 ng/mL to 10 ng/mL. The low-cost easy-to-use femtoMag platform offers high-sensitivity/high-precision target analyte quantification and promises to bring state-of-the-art medical diagnostic tests to the point of care.