International Journal on Magnetic Particle Imaging IJMPI
Vol. 9 No. 1 Suppl 1 (2023): Int J Mag Part Imag

Proceedings Articles

Estimation of hydrodynamic size distribution of magnetic nanoparticles based on AC magnetization harmonics for magnetic immunoassay

Main Article Content

Yi Sun (Kyushu University), Haochen Zhang (Kyushu University), Shuya Yamamura (Kyushu University), Zhongzhou Du (Zhengzhou University of Light Industry), Takashi Yoshida (Kyushu University)


Magnetic nanoparticles (MNPs) have been widely studied for use in biomedical applications such as magnetic immunoassay. The hydrodynamic size distribution is an important physical characteristic for estimating the binding behavior in magnetic immunoassay. In this study, we proposed a method to estimate the hydrodynamic size distribution of MNPs based on the AC magnetization harmonics. The matrix equation of hydrodynamic size distribution was constructed based on the Fokker-Planck equation dominated by Brownian relaxation, and inversed by a Tikhonov regularization least squares algorithm. The simulation results show that the proposed method can accurately estimate the hydrodynamic size distribution, which is expected to useful for biosensor applications.

Article Details


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