Center for Systems Biology, Massachusetts General Hospital, 185 Cambridge St, CPZN 5206, Boston, MA 02114, U.S.A.
Beilstein J Nanotechnol. 2010;1:142-54. doi: 10.3762/bjnano.1.17. Epub 2010 Dec 16.
Rapid and accurate measurements of protein biomarkers, pathogens and cells in biological samples could provide useful information for early disease diagnosis, treatment monitoring, and design of personalized medicine. In general, biological samples have only negligible magnetic susceptibility. Thus, using magnetic nanoparticles for biosensing not only enhances sensitivity but also effectively reduces sample preparation needs. This review focuses on the use of magnetic nanoparticles for in vitro detection of biomolecules and cells based on magnetic resonance effects. This detection platform, termed diagnostic magnetic resonance (DMR), exploits magnetic nanoparticles as proximity sensors, which modulate the spin-spin relaxation time of water molecules surrounding molecularly-targeted nanoparticles. By developing more effective magnetic nanoparticle biosensors, DMR detection limits for various target moieties have been considerably improved over the last few years. Already, a library of magnetic nanoparticles has been developed, in which a wide range of targets, including DNA/mRNA, proteins, small molecules/drugs, bacteria, and tumor cells, have been quantified. More recently, the capabilities of DMR technology have been further advanced with new developments such as miniaturized nuclear magnetic resonance detectors, better magnetic nanoparticles and novel conjugational methods. These developments have enabled parallel and sensitive measurements to be made from small volume samples. Thus, the DMR technology is a highly attractive platform for portable, low-cost, and efficient biomolecular detection within a biomedical setting.
快速准确地测量生物样本中的蛋白质生物标志物、病原体和细胞，可以为早期疾病诊断、治疗监测和个性化医疗设计提供有用信息。一般来说，生物样本的磁化率可忽略不计。因此，使用磁性纳米粒子进行生物传感不仅可以提高灵敏度，还可以有效减少样品制备的需求。本综述重点介绍了基于磁共振效应的磁性纳米粒子在生物分子和细胞的体外检测中的应用。该检测平台称为诊断磁共振（DMR），利用磁性纳米粒子作为近场传感器，调节分子靶向纳米粒子周围水分子的自旋-自旋弛豫时间。通过开发更有效的磁性纳米粒子生物传感器，近年来，DMR 对各种靶标物质的检测限有了相当大的提高。已经开发出了一系列磁性纳米粒子，其中包括 DNA/mRNA、蛋白质、小分子/药物、细菌和肿瘤细胞等广泛的靶标物质都可以进行定量检测。最近，DMR 技术的功能通过微型化磁共振探测器、更好的磁性纳米粒子和新颖的偶联方法等新的发展得到了进一步的提高。这些发展使从小体积样本中进行平行和灵敏的测量成为可能。因此，DMR 技术是一种在生物医学环境中用于便携式、低成本和高效生物分子检测的极具吸引力的平台。
