@article{71c6617e6ed54116b10958d77dd9bddb,
title = "Magnetic Nanoparticle Images and Assaying Biomarkers via the Magnetic Relaxation of Biofunctionalized Nanoparticles Associated with Biotargets",
abstract = "This paper presents a novel assay of biomarkers consisting of alpha-fetaprotein (AFP) via the measurements of saturation magnetization and magnetic relaxation. The biofunctionalized magnetic nanoparticles (BMNs) were anti-alpha-fetaprotein (antiAFP) coated onto dextran-coated iron oxide nanoparticles, labeled as Fe3O4-antiAFP, and then conjugated with AFP biotargets. After a complete conjugation of AFP and Fe3O4-antiAFP, the BMNs were dried for magnetic measurements. Magnetic nanoparticle images were obtained from magnetic force microscopy with details regarding the transmission electron microscopy images. Findings show that the saturation magnetization Ms increases with a rise in the associated AFP concentration and the magnetic relaxation time τ also shows a rapid increase when the concentration of AFP is lower than 0.2 ppm. Thus, we demonstrate a sensitive platform for detecting biomarkers by characterizing Ms and τ with a sensitivity limit of 0.03-ppm AFP. The results can be attributed to the interparticle interactions and the N{\'e}el motion of magnetic moments in BMNs.",
keywords = "Alpha-fetoprotein (AFP), biofunctionalized magnetic nanoparticles (BMNs), magnetic relaxation, saturation magnetization",
author = "Wang, {Li Min} and Yang, {Tien Wei} and Wang, {Chih Yi} and Dong Shen and Chen, {Jian Ming} and Chen, {Kuen Lin} and Liao, {Shu Hsien}",
note = "Funding Information: Manuscript received October 5, 2018; revised November 21, 2018; accepted November 21, 2018. Date of publication December 5, 2018; date of current version September 18, 2019. This work was supported by the Ministry of Science and Technology of Taiwan under Grant 104-2112-M-002-008-MY2, Grant 103-2112-M-002-011-, and Grant 103-2112-M-005-005-MY3. The associate editor coordinating the review of this paper and approving it for publication was Dr. Pui-In Mak. (Corresponding author: Tien-Wei Yang.) L.-M. Wang, T.-W. Yang, C.-Y. Wang, and D. Shen are with the Department of Physics, National Taiwan University, Taipei 10617, Taiwan, and also with the Graduate Institute of Applied Physics, National Taiwan University, Taipei 10617, Taiwan (e-mail: liminwang@ntu.edu.tw; d02222018@ntu.edu.tw; tony7611@hotmail.com; sddtc888@gmail.com). Publisher Copyright: {\textcopyright} 2001-2012 IEEE.",
year = "2019",
month = oct,
day = "15",
doi = "10.1109/JSEN.2018.2884893",
language = "English",
volume = "19",
pages = "9004--9009",
journal = "IEEE Sensors Journal",
issn = "1530-437X",
publisher = "Institute of Electrical and Electronics Engineers Inc.",
number = "20",
}