Multifunctional silver-embedded magnetic nanoparticles as SERS nanoprobes and their applications.
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.
Jun
Bong-Hyun
BH
School of Chemical and Biological Engineering, Seoul National University, Seoul 151-747, Republic of Korea.
Noh
Mi Suk
MS
Kim
Jaeyun
J
Kim
Gunsung
G
Kang
Homan
H
Kim
Min-Soo
MS
Seo
Young-Tae
YT
Baek
Jongho
J
Kim
Jong-Ho
JH
Park
Juyoung
J
Kim
Seongyong
S
Kim
Yong-Kweon
YK
Hyeon
Taeghwan
T
Cho
Myung-Haing
MH
Jeong
Dae Hong
DH
Lee
Yoon-Sik
YS
D003460:Crystallization / Q000379:methods*; D046911:Macromolecular Substances / Q000737:chemistry; D008280:Magnetics; D008422:Materials Testing; D008968:Molecular Conformation; D015336:Molecular Probe Techniques; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D036103:Nanotechnology / Q000379:methods*; D010316:Particle Size; D012834:Silver / Q000737:chemistry*; D013059:Spectrum Analysis, Raman / Q000379:methods*; D013499:Surface Properties
D046911:Macromolecular Substances; D012834:Silver