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Synthesis, characterization, and cytotoxicity in human erythrocytes of multifunctional, magnetic, and luminescent nanocrystalline rare earth fluorides.

Grzyb T, Mrówczyńska L, Szczeszak A, Śniadecki Z, Runowski M, Idzikowski B, Lis S - J Nanopart Res (2015)

Bottom Line: The highest luminescence was observed for BaGdF5-based materials.The particles' magnetic characteristics were also preserved for samples in the form of a suspension in distilled water.The cytotoxicity studies against the human erythrocytes indicated that the synthesized nanoparticles are non-toxic because they did not cause the red blood cells shape changes nor did they alter their membrane structure and permeabilization.

View Article: PubMed Central - PubMed

Affiliation: Department of Rare Earths, Faculty of Chemistry, Adam Mickiewicz University, Umultowska 89b, 61-614 Poznan, Poland.

ABSTRACT

Multifunctional nanoparticles exhibiting red or green luminescence properties and magnetism were synthesized and thoroughly analyzed. The hydrothermal method was used for the synthesis of Eu(3+)- or Tb(3+)-doped GdF3-, NaGdF4-, and BaGdF5-based nanocrystalline materials. The X-ray diffraction patterns of the samples confirmed the desired compositions of the materials. Transmission electron microscope images revealed the different morphologies of the products, including the nanocrystal sizes, which varied from 12 nm in the case of BaGdF5-based nanoparticles to larger structures with dimensions exceeding 300 nm. All of the samples presented luminescence under ultraviolet irradiation, as well as when the samples were in the form of water colloids. The highest luminescence was observed for BaGdF5-based materials. The obtained nanoparticles exhibited paramagnetism along with probable evidence of superparamagnetic behavior at low temperatures. The particles' magnetic characteristics were also preserved for samples in the form of a suspension in distilled water. The cytotoxicity studies against the human erythrocytes indicated that the synthesized nanoparticles are non-toxic because they did not cause the red blood cells shape changes nor did they alter their membrane structure and permeabilization.

No MeSH data available.


Related in: MedlinePlus

Temperature dependence of the magnetization M (left scale) and of the reciprocal DC magnetic susceptibility 1/χ (right scale) in GdF3:Ce3+,Eu3+, and NaGdF4:Ce3+,Eu3+. A comparison of GdF3:Ce3+,Eu3+ in powder and colloidal form is presented in the inset
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Fig4: Temperature dependence of the magnetization M (left scale) and of the reciprocal DC magnetic susceptibility 1/χ (right scale) in GdF3:Ce3+,Eu3+, and NaGdF4:Ce3+,Eu3+. A comparison of GdF3:Ce3+,Eu3+ in powder and colloidal form is presented in the inset

Mentions: Magnetic measurements were performed for four different powder samples (GdF3:Ce3+,Eu3+, GdF3:Ce3+,Tb3+, NaGdF4:Ce3+,Eu3+, and NaGdF4:Ce3+,Tb3+) and colloid of GdF3:Ce3+,Eu3+ suspended in distilled water. Due to the higher mass susceptibility of GdF3:Ce3+, one of these powders (with Eu3+ substitution) was chosen as the colloid solute. Temperature dependences of magnetization M(T) in the zero-field cooled (ZFC) and field cooled (FC) modes were measured in the temperature range of 2–300 K. The ZFC and FC curves were found to overlap each other. The curves measured for GdF3 with different substitutions are superimposed, as well as those for both NaGdF4-based samples. This result indicates that the influence of the substitution of Eu and Tb on the magnetic properties of the samples is roughly the same. As a consequence, only the results for Ce3+- and Eu3+-substituted samples are presented in Fig. 4. The results for Tb3+ substituted powders are shown in the Supplement (Figs. S1 and S2). Both M(T) curves coincide rather well over almost the entire temperature range, and the curves are typical for paramagnets. The magnetic properties of the Gd3+, which arise from seven unpaired inner 4f electrons, are responsible for such behavior. Gd3+ bonded with fluorine ions forms compounds, where the separation between the Gd3+ ions does not allow ferromagnetic interactions. In the inset of Fig. 4, the comparison of GdF3:Ce3+,Eu3+ as powder and water dispersed colloid is shown. The magnetization of the colloid was not divided per mass of the magnetic substance, but just rescaled to match the maximum value of the powder magnetization at 2 K. Hence, the mentioned M(T) curves should not be compared in a quantitative way. Qualitatively, the paramagnetic properties of GdF3:Ce3+,Eu3+ powder are preserved with increasing interparticle distance in the GdF3:Ce3+,Eu3+ colloid. This result suggests a lack of magnetic interparticle interactions. To expand the analysis of the magnetic data, the temperature dependences of the reciprocal DC magnetic susceptibility were plotted (Fig. 4—right axis). The DC magnetic susceptibility is defined as the quotient of M and H. Both curves for GdF3:Ce3+,Eu3+ and NaGdF4:Ce3+,Eu3+ follow the Curie–Weiss law, with paramagnetic Curie temperatures Θp equal to −1 and −2 K, respectively. The effective magnetic moments μeff per magnetic ion are comparable to that of free Gd3+ (7.94 μB): 7.83 μB for GdF3:Ce3+,Eu3+ and 8.13 μB for NaGdF4:Ce3+,Eu3+. The magnetic mass susceptibilities χg at 300 K are equal to 1.19 × 10−4 emu/(gOe) and 1.12 × 10−4 emu/(gOe) for GdF3:Ce3+,Eu3+ and NaGdF4:Ce3+,Eu3+, respectively. These values are slightly higher than magnetic mass susceptibilities determined for GdF3, GdF3:Eu3+, and NaGdF4:Yb3+,Er3+ (Wong et al. 2009; Wang et al. 2010, 2012). The magnetic behavior of all the GdF3 and NaGdF4 nanoparticles described above is governed by the independent dynamics of the magnetic moment of each rare earth ion.Fig. 4


Synthesis, characterization, and cytotoxicity in human erythrocytes of multifunctional, magnetic, and luminescent nanocrystalline rare earth fluorides.

Grzyb T, Mrówczyńska L, Szczeszak A, Śniadecki Z, Runowski M, Idzikowski B, Lis S - J Nanopart Res (2015)

Temperature dependence of the magnetization M (left scale) and of the reciprocal DC magnetic susceptibility 1/χ (right scale) in GdF3:Ce3+,Eu3+, and NaGdF4:Ce3+,Eu3+. A comparison of GdF3:Ce3+,Eu3+ in powder and colloidal form is presented in the inset
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

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Show All Figures
getmorefigures.php?uid=PMC4594090&req=5

Fig4: Temperature dependence of the magnetization M (left scale) and of the reciprocal DC magnetic susceptibility 1/χ (right scale) in GdF3:Ce3+,Eu3+, and NaGdF4:Ce3+,Eu3+. A comparison of GdF3:Ce3+,Eu3+ in powder and colloidal form is presented in the inset
Mentions: Magnetic measurements were performed for four different powder samples (GdF3:Ce3+,Eu3+, GdF3:Ce3+,Tb3+, NaGdF4:Ce3+,Eu3+, and NaGdF4:Ce3+,Tb3+) and colloid of GdF3:Ce3+,Eu3+ suspended in distilled water. Due to the higher mass susceptibility of GdF3:Ce3+, one of these powders (with Eu3+ substitution) was chosen as the colloid solute. Temperature dependences of magnetization M(T) in the zero-field cooled (ZFC) and field cooled (FC) modes were measured in the temperature range of 2–300 K. The ZFC and FC curves were found to overlap each other. The curves measured for GdF3 with different substitutions are superimposed, as well as those for both NaGdF4-based samples. This result indicates that the influence of the substitution of Eu and Tb on the magnetic properties of the samples is roughly the same. As a consequence, only the results for Ce3+- and Eu3+-substituted samples are presented in Fig. 4. The results for Tb3+ substituted powders are shown in the Supplement (Figs. S1 and S2). Both M(T) curves coincide rather well over almost the entire temperature range, and the curves are typical for paramagnets. The magnetic properties of the Gd3+, which arise from seven unpaired inner 4f electrons, are responsible for such behavior. Gd3+ bonded with fluorine ions forms compounds, where the separation between the Gd3+ ions does not allow ferromagnetic interactions. In the inset of Fig. 4, the comparison of GdF3:Ce3+,Eu3+ as powder and water dispersed colloid is shown. The magnetization of the colloid was not divided per mass of the magnetic substance, but just rescaled to match the maximum value of the powder magnetization at 2 K. Hence, the mentioned M(T) curves should not be compared in a quantitative way. Qualitatively, the paramagnetic properties of GdF3:Ce3+,Eu3+ powder are preserved with increasing interparticle distance in the GdF3:Ce3+,Eu3+ colloid. This result suggests a lack of magnetic interparticle interactions. To expand the analysis of the magnetic data, the temperature dependences of the reciprocal DC magnetic susceptibility were plotted (Fig. 4—right axis). The DC magnetic susceptibility is defined as the quotient of M and H. Both curves for GdF3:Ce3+,Eu3+ and NaGdF4:Ce3+,Eu3+ follow the Curie–Weiss law, with paramagnetic Curie temperatures Θp equal to −1 and −2 K, respectively. The effective magnetic moments μeff per magnetic ion are comparable to that of free Gd3+ (7.94 μB): 7.83 μB for GdF3:Ce3+,Eu3+ and 8.13 μB for NaGdF4:Ce3+,Eu3+. The magnetic mass susceptibilities χg at 300 K are equal to 1.19 × 10−4 emu/(gOe) and 1.12 × 10−4 emu/(gOe) for GdF3:Ce3+,Eu3+ and NaGdF4:Ce3+,Eu3+, respectively. These values are slightly higher than magnetic mass susceptibilities determined for GdF3, GdF3:Eu3+, and NaGdF4:Yb3+,Er3+ (Wong et al. 2009; Wang et al. 2010, 2012). The magnetic behavior of all the GdF3 and NaGdF4 nanoparticles described above is governed by the independent dynamics of the magnetic moment of each rare earth ion.Fig. 4

Bottom Line: The highest luminescence was observed for BaGdF5-based materials.The particles' magnetic characteristics were also preserved for samples in the form of a suspension in distilled water.The cytotoxicity studies against the human erythrocytes indicated that the synthesized nanoparticles are non-toxic because they did not cause the red blood cells shape changes nor did they alter their membrane structure and permeabilization.

View Article: PubMed Central - PubMed

Affiliation: Department of Rare Earths, Faculty of Chemistry, Adam Mickiewicz University, Umultowska 89b, 61-614 Poznan, Poland.

ABSTRACT

Multifunctional nanoparticles exhibiting red or green luminescence properties and magnetism were synthesized and thoroughly analyzed. The hydrothermal method was used for the synthesis of Eu(3+)- or Tb(3+)-doped GdF3-, NaGdF4-, and BaGdF5-based nanocrystalline materials. The X-ray diffraction patterns of the samples confirmed the desired compositions of the materials. Transmission electron microscope images revealed the different morphologies of the products, including the nanocrystal sizes, which varied from 12 nm in the case of BaGdF5-based nanoparticles to larger structures with dimensions exceeding 300 nm. All of the samples presented luminescence under ultraviolet irradiation, as well as when the samples were in the form of water colloids. The highest luminescence was observed for BaGdF5-based materials. The obtained nanoparticles exhibited paramagnetism along with probable evidence of superparamagnetic behavior at low temperatures. The particles' magnetic characteristics were also preserved for samples in the form of a suspension in distilled water. The cytotoxicity studies against the human erythrocytes indicated that the synthesized nanoparticles are non-toxic because they did not cause the red blood cells shape changes nor did they alter their membrane structure and permeabilization.

No MeSH data available.


Related in: MedlinePlus