Multifunctional Silver-Embedded Magnetic Nanoparticles as SERS Nanoprobes and Their Applications

作者：Jun Bong Hyun; Noh Mi Suk; Kim Jaeyun; Kim Gunsung; Kang Homan; Kim Min Soo; Seo Young Tae; Baek Jongho; Kim Jong Ho; Park Juyoung; Kim Seongyong; Kim Yong Kweon; Hyeon Taeghwan; Cho Myung Haing^*; Jeong Dae Hong; Lee Yoon Sik

来源：Small, 2010, 6(1): 119-125.

DOI：10.1002/smll.200901459

• magnetic materials
• optically active materials
• silver nanoparticles
• surface-enhanced Raman scattering

In this study, surface-enhanced Raman spectroscopy (SERS)-encoded magnetic nanoparticles (NPs) are prepared and utilized as a multifunctional tagging material for cancer-cell targeting and separation. First, silver-embedded magnetic NPs are prepared, composed of an 18-nm magnetic core and a 16-nm-thick silica shell with silver NPs formed on the surface. After simple aromatic compounds are adsorbed on the silver-embedded magnetic NPs, they are coated with. silica to provide them with chemical and physical stability. The resulting silica-encapsulated magnetic NPs (M-SERS dots) produce strong SERS signals and have magnetic properties. In a model application as a tagging material, the M-SERS dots are successfully utilized for targeting breast-cancer cells (SKBR3) and floating leukemia cells (SP2/O). The targeted cancer cells can be easily separated from the untargeted cells using an external magnetic field. The separated targeted cancer cells exhibit a Raman signal originating from the M-SERS dots. This system proves to be an efficient tool for separating targeted cells. Additionally, the magnetic-field-induced hot spots, which can provide a 1000-times-stronger SERS intensity due to aggregation of the NPs, are studied.

• 出版日期2010-1-4