1887
banner image
No data available.
Please log in to see this content.
You have no subscription access to this content.
No metrics data to plot.
The attempt to load metrics for this article has failed.
The attempt to plot a graph for these metrics has failed.
Ferritin protein encapsulated photoluminescent rare earth nanoparticle
Rent:
Rent this article for
USD
10.1063/1.4816567
/content/aip/journal/jap/114/4/10.1063/1.4816567
http://aip.metastore.ingenta.com/content/aip/journal/jap/114/4/10.1063/1.4816567

Figures

Image of FIG. 1.
FIG. 1.

Effect of pH on nanoparticle synthesis. Nanoparticle formation ratio (NFR) (solid line, left) and apoferritin concentration in supernatant (broken line, right) at various pHs for (a) Y, (b) Eu, and (c) Tb. NFR was calculated by dividing the number of holoferritin molecules by the total number of protein molecules in TEM images. Initial protein concentration was 0.1 mg/ml in each case.

Image of FIG. 2.
FIG. 2.

TEM images of Y nanoparticles synthesized at pH 7.0. The samples were either (a) negatively stained by Nano-W or (b) left unstained. The insets in (b) are HRTEM images of amorphous (left) and crystal (right) nanoparticles. Selected area electron diffraction pattern of Y nanoparticles is shown in (c). The lattice spacing obtained from (c) was 0.307 nm for (1) and 0.189 nm for (2). These d-spacings correspond well to the YO lattice spacings of 0.306 and 0.187 nm for Miller indices (222) and (440), respectively.

Image of FIG. 3.
FIG. 3.

EDX spectra of (a) Y and (b) Y:Eu nanoparticles. The spectra were obtained from (a) a single nanoparticle and (b) an area of 4 × 4 m. Specific peaks were detected for Y Lα, Kα, and Eu Mα, Lα, and Lβ. Cu peaks originate from the specimen grid, while Si and C peaks originate from the supporting carbon film.

Image of FIG. 4.
FIG. 4.

Size distribution of Y nanoparticles in apoferritin (N = 810). The average nanoparticle diameter was 5.7 ± 0.9 nm.

Image of FIG. 5.
FIG. 5.

Excitation spectra of (a) Y:Eu nanoparticles and (b) bulk Y(OH):Eu at an emission wavelength of 614 nm. Eu molar content was 57% in both cases. Inset shows the expanded region from 280 to 400 nm.

Image of FIG. 6.
FIG. 6.

Emission spectra of (a) Eu and Y:Eu nanoparticles, and (b) bulk Eu(OH) and Y(OH):Eu at an excitation wavelength of 396 nm.

Image of FIG. 7.
FIG. 7.

Emission peak intensities at 614 nm for various Eu contents of Y:Eu nanoparticles (green triangles) and bulk Y(OH):Eu (open red circles) at 396 nm excitation. The peak intensities at 610 nm emission (excitation 248 nm) of sintered Y:Eu nanoparticles were also plotted (closed orange circles). The peak intensities are normalized with the highest peak of each sample.

Image of FIG. 8.
FIG. 8.

Emission spectra of sintered Eu, Y:Eu nanoparticles, (a) and bulk sample (b) at an excitation wavelength of 248 and 251 nm, respectively.

Image of FIG. 9.
FIG. 9.

Excitation spectra of (a) Y:Tb nanoparticles and (b) bulk Y(OH):Tb at an emission wavelength of 544 nm. Tb molar content was 41% in both cases. Inset shows the expanded region from 270 to 420 nm.

Image of FIG. 10.
FIG. 10.

Emission spectra of Tb and Y:Tb nanoparticles at 237 nm excitation.

Image of FIG. 11.
FIG. 11.

The peak intensities for varying Tb content. Circles show emission peaks at 544 nm from Y:Tb nanoparticles (excitation: 237 nm) and squares show emission peaks at 542 nm from sintered samples (excitation: 275 nm). The peak intensities are normalized with the highest peak of each sample.

Image of FIG. 12.
FIG. 12.

Emission spectra of sintered Tb and Y:Tb nanoparticles at 275 nm excitation.

Tables

Generic image for table
Table I.

Initial dopant concentration at synthesis and resultant Eu and Tb molar contents of the nanoparticle.

Loading

Article metrics loading...

/content/aip/journal/jap/114/4/10.1063/1.4816567
2013-07-25
2014-04-16
Loading

Full text loading...

This is a required field
Please enter a valid email address
752b84549af89a08dbdd7fdb8b9568b5 journal.articlezxybnytfddd
Scitation: Ferritin protein encapsulated photoluminescent rare earth nanoparticle
http://aip.metastore.ingenta.com/content/aip/journal/jap/114/4/10.1063/1.4816567
10.1063/1.4816567
SEARCH_EXPAND_ITEM