Limits...
Enhanced magnetic resonance imaging and staining of cancer cells using ferrimagnetic H-ferritin nanoparticles with increasing core size.

Cai Y, Cao C, He X, Yang C, Tian L, Zhu R, Pan Y - Int J Nanomedicine (2015)

Bottom Line: In vitro MRI of cell pellets after M-HFn labeling was performed at 7 T.Iron uptake of cells was analyzed by Prussian blue staining and inductively coupled plasma mass spectrometry.The saturation magnetization (M(s)), relaxivity, and peroxidase-like activity of synthesized M-HFn nanoparticles were monotonously increased with the size of ferrimagnetic cores.

View Article: PubMed Central - PubMed

Affiliation: France-China Bio-Mineralization and Nano-Structures Laboratory, Key Laboratory of the Earth and Planetary Physics, Institute of Geology and Geophysics, Chinese Academy of Sciences, People's Republic of China ; Paleomagnetism and Geochronology Laboratory, Key Laboratory of the Earth and Planetary Physics, Institute of Geology and Geophysics, Chinese Academy of Sciences, People's Republic of China ; University of Chinese Academy of Sciences, Beijing, People's Republic of China.

ABSTRACT

Purpose: This study is to demonstrate the nanoscale size effect of ferrimagnetic H-ferritin (M-HFn) nanoparticles on magnetic properties, relaxivity, enzyme mimetic activities, and application in magnetic resonance imaging (MRI) and immunohistochemical staining of cancer cells.

Materials and methods: M-HFn nanoparticles with different sizes of magnetite cores in the range of 2.7-5.3 nm were synthesized through loading different amounts of iron into recombinant human H chain ferritin (HFn) shells. Core size, crystallinity, and magnetic properties of those M-HFn nanoparticles were analyzed by transmission electron microscope and low-temperature magnetic measurements. The MDA-MB-231 cancer cells were incubated with synthesized M-HFn nanoparticles for 24 hours in Dulbecco's Modified Eagle's Medium. In vitro MRI of cell pellets after M-HFn labeling was performed at 7 T. Iron uptake of cells was analyzed by Prussian blue staining and inductively coupled plasma mass spectrometry. Immunohistochemical staining by using the peroxidase-like activity of M-HFn nanoparticles was carried out on MDA-MB-231 tumor tissue paraffin sections.

Results: The saturation magnetization (M(s)), relaxivity, and peroxidase-like activity of synthesized M-HFn nanoparticles were monotonously increased with the size of ferrimagnetic cores. The M-HFn nanoparticles with the largest core size of 5.3 nm exhibit the strongest saturation magnetization, the highest peroxidase activity in immunohistochemical staining, and the highest r2 of 321 mM(-1) s(-1), allowing to detect MDA-MB-231 breast cancer cells as low as 10(4) cells mL(-1).

Conclusion: The magnetic properties, relaxivity, and peroxidase-like activity of M-HFn nanoparticles are size dependent, which indicates that M-HFn nanoparticles with larger magnetite core can significantly enhance performance in MRI and staining of cancer cells.

No MeSH data available.


Related in: MedlinePlus

Size dependence of magnetic properties of M-HFn nanoparticles.Notes: The relationship between the core size of M-HFn nanoparticles and their (A) R-value, (B) Ms, and (C) Hc.Abbreviations: M-HFn, ferrimagnetic H-ferritin; Ms, saturation magnetization; Hc, coercivity; R, magnetostatic interaction parameter.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4388082&req=5

f3-ijn-10-2619: Size dependence of magnetic properties of M-HFn nanoparticles.Notes: The relationship between the core size of M-HFn nanoparticles and their (A) R-value, (B) Ms, and (C) Hc.Abbreviations: M-HFn, ferrimagnetic H-ferritin; Ms, saturation magnetization; Hc, coercivity; R, magnetostatic interaction parameter.

Mentions: The R-value of the Wohlfarth–Cisowski test of M-HFn1000 is 0.5, suggesting no magnetostatic interactions between the M-HFn cores. However, the R-value of M-HFn3000, M-HFn5000, and M-HFn7000 decreases slightly to 0.48, 0.44, and 0.40, respectively, suggesting weak magnetic interaction in these samples (Table 1 and Figure S1). With the increase in core sizes, the saturation magnetization (Ms), coercivity (Hc), and blocking temperature (Tb) of those samples measured at 5 K are increasing. Specifically, the M-HFn1000, M-HFn3000, M-HFn5000, and M-HFn7000 have Ms values of 5.9 Am2 kg−1, 15.2 Am2 kg−1, 27.6 Am2 kg−1, and 37.3 Am2 kg−1, Hc values of 4.62 mT, 8.28 mT, 19.87 mT, and 24.41 mT, and Tb values of 10 K, 13 K, 44 K, and 170 K, respectively (Figures 3 and S2 and Table 1).


Enhanced magnetic resonance imaging and staining of cancer cells using ferrimagnetic H-ferritin nanoparticles with increasing core size.

Cai Y, Cao C, He X, Yang C, Tian L, Zhu R, Pan Y - Int J Nanomedicine (2015)

Size dependence of magnetic properties of M-HFn nanoparticles.Notes: The relationship between the core size of M-HFn nanoparticles and their (A) R-value, (B) Ms, and (C) Hc.Abbreviations: M-HFn, ferrimagnetic H-ferritin; Ms, saturation magnetization; Hc, coercivity; R, magnetostatic interaction parameter.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4388082&req=5

f3-ijn-10-2619: Size dependence of magnetic properties of M-HFn nanoparticles.Notes: The relationship between the core size of M-HFn nanoparticles and their (A) R-value, (B) Ms, and (C) Hc.Abbreviations: M-HFn, ferrimagnetic H-ferritin; Ms, saturation magnetization; Hc, coercivity; R, magnetostatic interaction parameter.
Mentions: The R-value of the Wohlfarth–Cisowski test of M-HFn1000 is 0.5, suggesting no magnetostatic interactions between the M-HFn cores. However, the R-value of M-HFn3000, M-HFn5000, and M-HFn7000 decreases slightly to 0.48, 0.44, and 0.40, respectively, suggesting weak magnetic interaction in these samples (Table 1 and Figure S1). With the increase in core sizes, the saturation magnetization (Ms), coercivity (Hc), and blocking temperature (Tb) of those samples measured at 5 K are increasing. Specifically, the M-HFn1000, M-HFn3000, M-HFn5000, and M-HFn7000 have Ms values of 5.9 Am2 kg−1, 15.2 Am2 kg−1, 27.6 Am2 kg−1, and 37.3 Am2 kg−1, Hc values of 4.62 mT, 8.28 mT, 19.87 mT, and 24.41 mT, and Tb values of 10 K, 13 K, 44 K, and 170 K, respectively (Figures 3 and S2 and Table 1).

Bottom Line: In vitro MRI of cell pellets after M-HFn labeling was performed at 7 T.Iron uptake of cells was analyzed by Prussian blue staining and inductively coupled plasma mass spectrometry.The saturation magnetization (M(s)), relaxivity, and peroxidase-like activity of synthesized M-HFn nanoparticles were monotonously increased with the size of ferrimagnetic cores.

View Article: PubMed Central - PubMed

Affiliation: France-China Bio-Mineralization and Nano-Structures Laboratory, Key Laboratory of the Earth and Planetary Physics, Institute of Geology and Geophysics, Chinese Academy of Sciences, People's Republic of China ; Paleomagnetism and Geochronology Laboratory, Key Laboratory of the Earth and Planetary Physics, Institute of Geology and Geophysics, Chinese Academy of Sciences, People's Republic of China ; University of Chinese Academy of Sciences, Beijing, People's Republic of China.

ABSTRACT

Purpose: This study is to demonstrate the nanoscale size effect of ferrimagnetic H-ferritin (M-HFn) nanoparticles on magnetic properties, relaxivity, enzyme mimetic activities, and application in magnetic resonance imaging (MRI) and immunohistochemical staining of cancer cells.

Materials and methods: M-HFn nanoparticles with different sizes of magnetite cores in the range of 2.7-5.3 nm were synthesized through loading different amounts of iron into recombinant human H chain ferritin (HFn) shells. Core size, crystallinity, and magnetic properties of those M-HFn nanoparticles were analyzed by transmission electron microscope and low-temperature magnetic measurements. The MDA-MB-231 cancer cells were incubated with synthesized M-HFn nanoparticles for 24 hours in Dulbecco's Modified Eagle's Medium. In vitro MRI of cell pellets after M-HFn labeling was performed at 7 T. Iron uptake of cells was analyzed by Prussian blue staining and inductively coupled plasma mass spectrometry. Immunohistochemical staining by using the peroxidase-like activity of M-HFn nanoparticles was carried out on MDA-MB-231 tumor tissue paraffin sections.

Results: The saturation magnetization (M(s)), relaxivity, and peroxidase-like activity of synthesized M-HFn nanoparticles were monotonously increased with the size of ferrimagnetic cores. The M-HFn nanoparticles with the largest core size of 5.3 nm exhibit the strongest saturation magnetization, the highest peroxidase activity in immunohistochemical staining, and the highest r2 of 321 mM(-1) s(-1), allowing to detect MDA-MB-231 breast cancer cells as low as 10(4) cells mL(-1).

Conclusion: The magnetic properties, relaxivity, and peroxidase-like activity of M-HFn nanoparticles are size dependent, which indicates that M-HFn nanoparticles with larger magnetite core can significantly enhance performance in MRI and staining of cancer cells.

No MeSH data available.


Related in: MedlinePlus