期刊
ACS APPLIED MATERIALS & INTERFACES
卷 4, 期 8, 页码 3923-3931出版社
AMER CHEMICAL SOC
DOI: 10.1021/am300750s
关键词
Au; Ag; AgcoreAushell; dopamine; aggregation; plasmon absorption; SERS
资金
- National Research Foundation of Korea (NRF)
- Korea government (MEST) [20090093908]
- National Research Foundation of Korea
- Korean Government (MEST) [NRF-2010-C1AAA001-2010-0028958]
Gold (Au), silver (Ag), and AgcoreAushell nanoparticles (NPs) were explored as optical sensing agents for the sensitive detection of dopamine (DA) neurotransmitters in surface-enhanced Raman scattering (SERS) measurements. In these colloidal systems, dopamine (DA) molecules played as a cross-linker between M NPs (Au or Ag NPs), allowing them to reside in the confined junctions (i.e., hot spots) between aggregated NPs. The progressive addition of DA molecules (from 1 X 10(-6) to 1 X 10(-3) M) consequently. decreased a primary absorption peak attributed to the characteristic M NPs and generated a secondary absorption peak at longer wavelengths attributed to heavily aggregated M NPs formed by molecular bridging, effects of DA molecules at high concentrations. The aggregation degree of M NPs was also dependent on the surface states of Au and Ag NPs, i.e., DA molecules with positive amine groups induced more aggregations of Au NPs in comparison to Ag NPs with less negative charges. As the final outcome, Au NPs demonstrated higher sensitivity in SERS detection of DA at low concentrations (1 x 10(-7) to 1 x 10(-5) M), whereas Ag NPs exhibited the stronger Raman signals of DA molecules at high concentrations (1 X 10(-4) to 1 x 10(-3) M). Besides, AgcoreAushell NPs with the lowest surface coverage of Au shell exhibited more sensitive and stronger SERS activity for DA molecules than that of singular Au NPs, probably due to the combined contribution by Ag core with strong SEAS intensity and Au shell with high SEAS sensitivity
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据