Limits...
Co-enhancement of fluorescence and singlet oxygen generation by silica-coated gold nanorods core-shell nanoparticle.

Ke X, Wang D, Chen C, Yang A, Han Y, Ren L, Li D, Wang H - Nanoscale Res Lett (2014)

Bottom Line: Metal-enhanced fluorescence (MEF) as a newly recognized technology has been attracting considerable attention and is widely used in fluorescence-based technology.In this paper, we reported a novel distance-dependent MEF and metal-enhanced singlet oxygen generation phenomenon based on silica-coated gold nanorods (AuNRs@SiO2) core-shell structure with tetra-substituted carboxyl aluminum phthalocyanine (AlC4Pc) that serve as both fluorophore and photosensitizer.When the AlC4Pc was linked on the surface of AuNRs@SiO2, the fluorescence intensity and singlet oxygen productivity varied with the thickness difference of silica shell from 2.1 to 28.6 nm.

View Article: PubMed Central - PubMed

Affiliation: Department of Biomaterials, College of Materials, Xiamen University, Xiamen, 361005, People's Republic of China, kcc2691@126.com.

ABSTRACT
Metal-enhanced fluorescence (MEF) as a newly recognized technology has been attracting considerable attention and is widely used in fluorescence-based technology. In this paper, we reported a novel distance-dependent MEF and metal-enhanced singlet oxygen generation phenomenon based on silica-coated gold nanorods (AuNRs@SiO2) core-shell structure with tetra-substituted carboxyl aluminum phthalocyanine (AlC4Pc) that serve as both fluorophore and photosensitizer. When the AlC4Pc was linked on the surface of AuNRs@SiO2, the fluorescence intensity and singlet oxygen productivity varied with the thickness difference of silica shell from 2.1 to 28.6 nm. The co-enhancement effect reached the maximum of 7-fold and 2.1-fold, respectively, when the separation distance was 10.6 nm. These unique characteristics make the prepared core-shell nanoparticles promising for MEF-based biological imaging and photodynamics therapy.

No MeSH data available.


Related in: MedlinePlus

Fluorescence spectra and fluorescence decay. (a) Fluorescence spectra corresponding to the samples in Figure 1a,b,c,d,e,f. Inset: Distance-dependent fluorescence enhancement factor of AuNRs@SiO2-AlC4Pc. (b) Fluorescence decay of AuNRs@SiO2-AlC4Pc with 10.6 nm shell thickness and free AlC4Pc. The instrument response function (IRF) is included λem = 591 nm.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4493993&req=5

Fig5: Fluorescence spectra and fluorescence decay. (a) Fluorescence spectra corresponding to the samples in Figure 1a,b,c,d,e,f. Inset: Distance-dependent fluorescence enhancement factor of AuNRs@SiO2-AlC4Pc. (b) Fluorescence decay of AuNRs@SiO2-AlC4Pc with 10.6 nm shell thickness and free AlC4Pc. The instrument response function (IRF) is included λem = 591 nm.

Mentions: As depicted in Figure 5a, a 2.9-fold fluorescence enhancement was observed when the AuNRs-AlC4Pc separation distance was 2.1 nm. With an increase of the spacer thickness from 2.1 to 10.6 nm, the enhancement factor of MEF gradually increased and reached its maximum of 7.1 at 10.6 nm. This could be explained by that with the increase of silica shell, the local electromagnetic field enhancement effect became remarkable while the non-radiative decay from AlC4Pc to gold core could be negligible due to the short-range effect [9, 15]. However, a further increase of silica layer thickness caused an obvious decline of EFMEF. Because the positions of AlC4Pc molecules were beyond the effective electromagnetic field enhancement range, thus the interaction of AlC4Pc with gold core were weakened and gradually disappeared. Therefore, when the AlC4Pc molecule was too close or too far to the AuNRs, MEF effect could be diminished by non-radiative energy transfer or weak electromagnetic field, respectively.Figure 5


Co-enhancement of fluorescence and singlet oxygen generation by silica-coated gold nanorods core-shell nanoparticle.

Ke X, Wang D, Chen C, Yang A, Han Y, Ren L, Li D, Wang H - Nanoscale Res Lett (2014)

Fluorescence spectra and fluorescence decay. (a) Fluorescence spectra corresponding to the samples in Figure 1a,b,c,d,e,f. Inset: Distance-dependent fluorescence enhancement factor of AuNRs@SiO2-AlC4Pc. (b) Fluorescence decay of AuNRs@SiO2-AlC4Pc with 10.6 nm shell thickness and free AlC4Pc. The instrument response function (IRF) is included λem = 591 nm.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4493993&req=5

Fig5: Fluorescence spectra and fluorescence decay. (a) Fluorescence spectra corresponding to the samples in Figure 1a,b,c,d,e,f. Inset: Distance-dependent fluorescence enhancement factor of AuNRs@SiO2-AlC4Pc. (b) Fluorescence decay of AuNRs@SiO2-AlC4Pc with 10.6 nm shell thickness and free AlC4Pc. The instrument response function (IRF) is included λem = 591 nm.
Mentions: As depicted in Figure 5a, a 2.9-fold fluorescence enhancement was observed when the AuNRs-AlC4Pc separation distance was 2.1 nm. With an increase of the spacer thickness from 2.1 to 10.6 nm, the enhancement factor of MEF gradually increased and reached its maximum of 7.1 at 10.6 nm. This could be explained by that with the increase of silica shell, the local electromagnetic field enhancement effect became remarkable while the non-radiative decay from AlC4Pc to gold core could be negligible due to the short-range effect [9, 15]. However, a further increase of silica layer thickness caused an obvious decline of EFMEF. Because the positions of AlC4Pc molecules were beyond the effective electromagnetic field enhancement range, thus the interaction of AlC4Pc with gold core were weakened and gradually disappeared. Therefore, when the AlC4Pc molecule was too close or too far to the AuNRs, MEF effect could be diminished by non-radiative energy transfer or weak electromagnetic field, respectively.Figure 5

Bottom Line: Metal-enhanced fluorescence (MEF) as a newly recognized technology has been attracting considerable attention and is widely used in fluorescence-based technology.In this paper, we reported a novel distance-dependent MEF and metal-enhanced singlet oxygen generation phenomenon based on silica-coated gold nanorods (AuNRs@SiO2) core-shell structure with tetra-substituted carboxyl aluminum phthalocyanine (AlC4Pc) that serve as both fluorophore and photosensitizer.When the AlC4Pc was linked on the surface of AuNRs@SiO2, the fluorescence intensity and singlet oxygen productivity varied with the thickness difference of silica shell from 2.1 to 28.6 nm.

View Article: PubMed Central - PubMed

Affiliation: Department of Biomaterials, College of Materials, Xiamen University, Xiamen, 361005, People's Republic of China, kcc2691@126.com.

ABSTRACT
Metal-enhanced fluorescence (MEF) as a newly recognized technology has been attracting considerable attention and is widely used in fluorescence-based technology. In this paper, we reported a novel distance-dependent MEF and metal-enhanced singlet oxygen generation phenomenon based on silica-coated gold nanorods (AuNRs@SiO2) core-shell structure with tetra-substituted carboxyl aluminum phthalocyanine (AlC4Pc) that serve as both fluorophore and photosensitizer. When the AlC4Pc was linked on the surface of AuNRs@SiO2, the fluorescence intensity and singlet oxygen productivity varied with the thickness difference of silica shell from 2.1 to 28.6 nm. The co-enhancement effect reached the maximum of 7-fold and 2.1-fold, respectively, when the separation distance was 10.6 nm. These unique characteristics make the prepared core-shell nanoparticles promising for MEF-based biological imaging and photodynamics therapy.

No MeSH data available.


Related in: MedlinePlus