Materials
·
2024
·Vol. 17
·期 2
·509
·
IF 3.1
Shuya Ning,Shuo Wang,Zhihui Liu,Naming Zhang,Bin Yang,Fanghui Zhang
Magnetic–plasmonic nanoparticles (NPs) have attracted great interest in many fields because they can exhibit more physical and chemical properties than individual magnetic or plasmonic NPs. In this work, we synthesized Au- or Ag-decorated Fe3O4nanoparticles coated with PEI (Fe3O4-PEI-M (M = Au or Ag) NPs) using a simple method. The influences of the plasmonic metal NPs’ (Au or Ag) coating density on the magnetic and plasmonic properties of the Fe3O4-PEI-M (M = Au or Ag) NPs were investigated, and the density of the plasmonic metal NPs coated on the Fe3O4NPs surfaces could be adjusted by controlling the polyethyleneimine (PEI) concentration. It showed that the Fe3O4-PEI-M (M = Au or Ag) NPs exhibited both magnetic and plasmonic properties. When the PEI concentration increased from 5 to 35 mg/mL, the coating density of the Au or Ag NPs on the Fe3O4NPs surfaces increased, the corresponding magnetic intensity became weaker, and the plasmonic intensity was stronger. At the same time, the plasmonic resonance peak of the Fe3O4-PEI-M (M = Au or Ag) NPs was red shifted. Therefore, there was an optimal coverage of the plasmonic metal NPs on the Fe3O4NPs surfaces to balance the magnetic and plasmonic properties when the PEI concentration was between 15 and 25 mg/mL. This result can guide the application of the Fe3O4-M (M = Au or Ag) NPs in the biomedical field.
研究领域:
纳米材料科学
·
生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Small
·
2020
·Vol. 16
·期 37
·2002748
·
IF 11.459
Kai Cai,Weiyun Zhang,Mohamed F. Foda,Xuyu Li,Jin Zhang,Yeteng Zhong,Huageng Liang,Huiqiao Li,Heyou Han,Tianyou Zhai
The miniaturization of gold nanorods exhibits a bright prospect for intravital photoacoustic imaging (PAI) and the hollow structure possesses a better plasmonic property. Herein, miniature hollow gold nanorods (M-AuHNRs) (≈46 nm in length) possessing strong plasmonic absorbance in the second near-infrared (NIR-II) window (1000–1350 nm) are developed, which are considered as the most suitable range for the intravital PAI. The as-prepared M-AuHNRs exhibit 3.5 times stronger photoacoustic signal intensity than the large hollow Au nanorods (≈105 nm in length) at 0.2 optical density under 1064 nm laser irradiation. The in vivo biodistribution measurement shows that the accumulation in tumor of miniature nanorods is twofold as high as that of the large counterpart. After modifying with a tumor-targeting molecule and fluorochrome, in living tumor-bearing mice, the M-AuHNRs group gives a high fluorescence intensity in tumors, which is 3.6-fold that of the large ones with the same functionalization. Moreover, in the intravital PAI of living tumor-bearing mice, the M-AuHNRs generate longer-lasting and stronger photoacoustic signal than the large counterpart in the NIR-II window. Overall, this study presents the fabrication of M-AuHNRs as a promising contrast agent for intravital PAI.
研究领域:
纳米技术
·
生物医学工程
·
成像科学
✓ 已验证
DOI
PubMed
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2016
·Vol. 41
·期 4
·1582-1590
·
IF 3.277
Qinye He,Aiwu Zhao,Lei Li,Henghui Sun,Dapeng Wang,Hongyan Guo,Mei Sun,Ping Chen
Fe3O4@SiO2@Ag magnetic–plasmonic nanospindles with efficient SERS performance and magnetic responsiveness have been successfully fabricated. Uniform and monodispersed Fe3O4@SiO2 nanospindles were prepared by a robust strategy through annealing the obtained β-FeOOH@SiO2 nanospindles in hydrogen atmospheres at 350 °C; the SiO2 shell could be regarded as an interlayer to maintain the morphology and offer a solid support for the further growth of Ag nanoparticles. Ag nanoparticles were introduced via in situ reduction of AgNO3, and the coverage rate of Ag nanoparticles anchored on Fe3O4@SiO2 was adjusted through regulating the AgNO3 concentration. Fe3O4@SiO2@Ag magnetic–plasmonic nanospindles can serve as highly efficient SERS active substrates with controllable magnetic aggregation due to steady enrichment of mass molecules in close proximity to abundant hot spots. Moreover, these nanospindles are used for label-free detection of thiram, and the detection limit is as low as 1 × 10−7 M (about 0.024 ppm), which is lower than the maximal residue limit of 7 ppm in fruits prescribed by the U.S. Environmental Protection Agency. Therefore, such magnetic–plasmonic nanospindles in the magnetic aggregation state may be potentially applied in rapid trace detection of residual pesticides or other specific analytes.
研究领域:
材料科学
·
分析化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Physical Chemistry C
·
2015
·
IF 4.772
Rui Wang,Xiaohui Ji,Zhenzhen Huang,Yurui Xue,Dayang Wang,Wensheng Yang
In this work, SiO2@Au core–shell particles under ambient conditions were prepared by using 120 nm SiO2 spheres with ca. 4 nm Au nanoparticles decorated on the surfaces as seeds, the aqueous solutions of sodium citrate/HAuCl4 mixtures as growth solutions, and hydroxylamine as reducing agent. The morphology of the Au shells obtained on the SiO2 spheres was readily regulated only by the citrate-to-HAuCl4 molar ratio; no deliberate adjustment of the temperature and pH of the reaction media was needed. When the citrate-to-HAuCl4 molar ratio in the growth solution was below 4:1, the surfaces of the SiO2 spheres were covered with sparsely packed Au nanoparticles with sizes in the range of 20–40 nm, depending on the citrate-to-HAuCl4 molar ratio. When the citrate-to-HAuCl4 molar ratio in the growth solution was above 8:1, the surfaces of the SiO2 spheres were coated by complete, uniform Au nanoshells. Concomitant with this citrate-regulated morphology, the localized surface plasmon resonance peaks of the resulting SiO2@Au particles shifted from 611 nm for the sparse Au nanoparticle coating to 784 nm for the complete Au nanoshell coating. Furthermore, the sparsely packed Au nanoparticle coating showed stronger surface enhancement Raman spectroscopic signals than the uniform Au nanoshell coating, while the latter exhibit higher photothermal efficiency than the former.
研究领域:
材料科学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
PARTICLE & PARTICLE SYSTEMS CHARACTERIZATION
·
2025
·
IF 3
Zhen-Ming Shen,Jie Liu,Kun-Peng Wang,Xi-Hao Zhang,Lan Chen,Zhigang Zhou,Tian-Song Deng
Hollow core-shell noble metallic nanoparticles have garnered significant attention due to their plasmonic properties, which are markedly enhanced by the hollow structure. However, precisely controlling the size and shape of the shell and cavity in such structures remains a challenge. Here, a novel strategy is reported that eliminates the need for etchants, utilizing monodispersed gold nanorods (AuNRs) as templates to synthesize hollow Au@AuAg core-shell nanostructures. By precisely regulating the CTAB/CTAC and Au/Ag ratios during the co-deposition of Au and Ag atoms onto the AuNRs, uniform bimetallic hollow shells are achieved without the use of corrosive etching agents. High-resolution TEM and EDS characterizations confirm the formation of crystalline AuAg alloy shells surrounding the AuNRs cores, with well-defined cavities. Compared to pure silver shells, the AuAg alloy shells exhibit superior stability. Furthermore, the resulting Au@AuAg nanostructures with hollow shells demonstrate significantly enhanced refractive index sensitivity and surface-enhanced Raman scattering (SERS) activity relative to pristine AuNRs, making them highly promising for biomedical applications such as biosensing and bioimaging.
研究领域:
纳米技术
·
材料科学
·
等离子体光子学
·
分析化学
·
生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）