TY - JOUR
T1 - Membrane Surface-Enhanced Raman Spectroscopy for Cholesterol-Modified Lipid Systems
T2 - Effect of Gold Nanoparticle Size
AU - Faried, Miftah
AU - Suga, Keishi
AU - Okamoto, Yukihiro
AU - Shameli, Kamyar
AU - Miyake, Mikio
AU - Umakoshi, Hiroshi
N1 - Funding Information:
This work was primarily supported by the Japan Society for the Promotion of Science (JSPS) KAKENHI Grant-in-Aids for Scientific Research (A) (26249116), Grant-in-Aids for Young Scientists (B) (16K18279), Grant-in-Aids for Challenging Exploratory Research (T15K142040), and Early-Career Scientists (19K15338). The authors express their gratitude for Dr. Haruyuki Ishii (Yamaguchi University) for synthesis of 5 nm AuNP samples. M.F. expresses his gratitude for the Japanese Government (Monbukagakusho: MEXT) scholarship.
Publisher Copyright:
Copyright © 2019 American Chemical Society.
PY - 2019/8/27
Y1 - 2019/8/27
N2 - A gold nanoparticle (AuNP) has a localized surface plasmon resonance peak depending on its size, which is often utilized for surface-enhanced Raman scattering (SERS). To obtain information on the cholesterol (Chol)-incorporated lipid membranes by SERS, AuNPs (5, 100 nm) were first functionalized by 1-octanethiol and then modified by lipids (AuNP@lipid). In membrane surface-enhanced Raman spectroscopy (MSERS), both signals from 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) and Chol molecules were enhanced, depending on preparation conditions (size of AuNPs and lipid/AuNP ratio). The enhancement factors (EFs) were calculated to estimate the efficiency of AuNPs on Raman enhancement. The size of AuNP100nm@lipid was 152.0 ± 12.8 nm, which showed an surface enhancement Raman spectrum with an EF2850 value of 111 ± 9. The size of AuNP5nm@lipid prepared with a lipid/AuNP ratio of 1.38 × 104 (lipid molecule/particle) was 275.3 ± 20.2 nm, which showed the highest enhancement with an EF2850 value of 131 ± 21. On the basis of fluorescent probe analyses, the membrane fluidity and polarity of AuNP@lipid were almost similar to DOPC/Chol liposome, indicating an intact membrane of DOPC/Chol after modification with AuNPs. Finally, the membrane properties of AuNP@lipid systems were also discussed on the basis of the obtained MSERS signals.
AB - A gold nanoparticle (AuNP) has a localized surface plasmon resonance peak depending on its size, which is often utilized for surface-enhanced Raman scattering (SERS). To obtain information on the cholesterol (Chol)-incorporated lipid membranes by SERS, AuNPs (5, 100 nm) were first functionalized by 1-octanethiol and then modified by lipids (AuNP@lipid). In membrane surface-enhanced Raman spectroscopy (MSERS), both signals from 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) and Chol molecules were enhanced, depending on preparation conditions (size of AuNPs and lipid/AuNP ratio). The enhancement factors (EFs) were calculated to estimate the efficiency of AuNPs on Raman enhancement. The size of AuNP100nm@lipid was 152.0 ± 12.8 nm, which showed an surface enhancement Raman spectrum with an EF2850 value of 111 ± 9. The size of AuNP5nm@lipid prepared with a lipid/AuNP ratio of 1.38 × 104 (lipid molecule/particle) was 275.3 ± 20.2 nm, which showed the highest enhancement with an EF2850 value of 131 ± 21. On the basis of fluorescent probe analyses, the membrane fluidity and polarity of AuNP@lipid were almost similar to DOPC/Chol liposome, indicating an intact membrane of DOPC/Chol after modification with AuNPs. Finally, the membrane properties of AuNP@lipid systems were also discussed on the basis of the obtained MSERS signals.
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U2 - 10.1021/acsomega.9b01073
DO - 10.1021/acsomega.9b01073
M3 - Article
AN - SCOPUS:85071910140
VL - 4
SP - 13687
EP - 13695
JO - ACS Omega
JF - ACS Omega
SN - 2470-1343
IS - 9
ER -