A Feasibility Study of Nonlinear Spectroscopic Measurement of Magnetic Nanoparticles Targeted to Cancer Cells

Abstract

Objective Magnetic nanoparticles (MNPs) are an emerging platform for targeted diagnostics in cancer. An important component needed for translation of MNPs is the detection and quantification of targeted MNPs bound to tumor cells. Method This study explores the feasibility of a multi-frequency nonlinear magnetic spectroscopic method that uses excitation and pick-up coils and is capable of discriminating between quantities of bound and unbound MNPs in 0.5 ml samples of KB and Igrov human cancer cell lines. The method is tested over a range of five concentrations of MNPs from 0 to 80 μg /ml and five concentrations of cells from 50 to 400 thousand count per ml. Results A linear model applied to the magnetic spectroscopy data was able to simultaneously measure bound and unbound MNPs with agreement between the model-fit and lab assay measurements (p<0.001). The detectable iron of the presented method to bound and unbound MNPs was < 2 μg in a 0.5 ml sample. The linear model parameters used to determine the quantities of bound and unbound nanoparticles in KB cells were also used to measure the bound and unbound MNP in the Igrov cell line and vice versa. Conclusion Nonlinear spectroscopic measurement of magnetic nanoparticles may be a useful method for studying targeted MNPs in oncology. Significance Determining the quantity of bound and unbound MNP in an unknown sample using a linear model represents an exciting opportunity to translate multi-frequency nonlinear spectroscopy methods to in vivo applications where MNPs could be targeted to cancer cells.

Nanomagnetic Actuation of Hybrid Stents for Hyperthermia Treatment of Hollow Organ Tumors

“…For PP@5%MNP and PP@7%MNP, a less pronounced decrease of only 15% and 22% is observed. Such decrease in A5/A3 was recently reported for immobilized particles [37] and for particles agglomerated inside living cells [82]. Furthermore, this trend confirms the presence of stronger dipole-dipole interactions inside PP@3%MNP filaments as already deduced from the ZFC peak shift (Figure 5b) and susceptibility values (Figure 6a).…”

Comparative Modeling of Frequency Mixing Measurements of Magnetic Nanoparticles Using Micromagnetic Simulations and Langevin Theory

“…Clustering of MNPs has been suggested to lead to increased particle–particle interaction, changed effective anisotropy, and restriction of MNP rotatability [ 38 , 39 , 40 ]. Although the interplay of these clustering effects on MNP relaxation behavior is the subject of ongoing discussions [ 39 , 40 , 41 , 42 ], it is overall assumed to diminish the experimental signal intensity [ 43 ]. Both the rise of particle–particle interaction—although purposefully excluded from this study—and the influence of varying could be investigated in future MC-simulations studies (e.g., by diffusion-limited colloidal aggregation [ 42 ]) to advance the understanding of its influence on mixed frequency excitation signal generation.…”

Experimental comparison of four nonlinear magnetic detection methods and considerations on clinical usability

“…MPS has been used to measure temperature (Wells et al 2017) and viscosity (Elrefai et al 2020), for biomolecule imaging (Zhong et al 2020) and to distinguish different SPIONs (Viereck et al 2019). There are various ways to carry out MPS, including frequency mixing (Nikitin et al 2018, Wu et al 2015, Ficko et al 2017, second harmonic detection (Jamil et Much is still unknown about the effects of exposure to low frequency electromagnetic fields (between 1 Hz and 100 kHz). However, there are risks of exposure to fields above a frequency dependent threshold.…”