title: Detection of the mycotoxin citrinin using silver substrates and Raman spectroscopy.
abstract: We detected a trace amount of the mycotoxin citrinin using surface-enhanced Raman scattering (SERS) on silver nanoparticle (Ag NP) surfaces. The SERS substrate on hydrophobic Teflon films was also introduced to observe the citrinin peaks. A broad band at ∼1382cm(-1), which was ascribed to the symmetric carboxylate stretching mode, was observed in addition to an antisymmetric carboxylate stretching mode at ∼1568cm(-1) in the Raman spectra. The spectral feature indicated that citrinin would adsorb on Ag NPs via its carboxylate form. Based on density functional theory (DFT) calculations, vibrational mode analysis was performed to compare the Raman spectra of citrinin. DFT calculations also predicted that a bidentate bridge configuration through O15 and O16 atoms in citrinin would be the most stable on three Ag atoms. After treating with Ag NPs, observation of citrinin peaks was attempted in fungal cells of Penicillium citrinum. This work may provide useful insights into the direct observation of the hazardous citrinin mycotoxin using SERS by understanding its adsorption behaviors on Ag surfaces.
authors: Department of Chemistry, Soongsil University, Seoul 156-743, South Korea.
authors: Dheeraj K
authors: DK
authors: Singh
authors: Department of Chemistry, Soongsil University, Seoul 156-743, South Korea.
authors: Erdene-Ochir
authors: EO
authors: Ganbold
authors: College of Environment and Applied Chemistry, Kyung Hee University, Yongin 446-701, South Korea.
authors: Eun-Min
authors: EM
authors: Cho
authors: School of Systems Biomedical Science, Soongsil University, Sangdo-dong, Dongjak-gu, Seoul, South Korea.
authors: Kwang-Hwi
authors: KH
authors: Cho
authors: Department of Physics, Sogang University, Seoul 121-742, South Korea.
authors: Doseok
authors: D
authors: Kim
authors: Department of Bionano Engineering, Hanyang University, Sa-1-dong 1271, Ansan 426-791, South Korea.
authors: Jaebum
authors: J
authors: Choo
authors: Molecular-level Interface Research Center and Department of Chemistry, KAIST, Daejeon 305-701, South Korea.
authors: Sehun
authors: S
authors: Kim
authors: Institute of Environmental and Industrial Medicine, Hanyang University, 17 Haengdang-dong, Seongdong-gu, Seoul 133-791, South Korea. Electronic address: spica@hanyang.ac.kr.
authors: Cheol Min
authors: CM
authors: Lee
authors: College of Environment and Applied Chemistry, Kyung Hee University, Yongin 446-701, South Korea. Electronic address: siyang@khu.ac.kr.
authors: Sung Ik
authors: SI
authors: Yang
authors: Department of Chemistry, Soongsil University, Seoul 156-743, South Korea. Electronic address: sjoo@ssu.ac.kr.
authors: Sang-Woo
authors: SW
authors: Joo
mesh_terms: D000327:Adsorption; D002953:Citrinin / Q000032:analysis* / Q000737:chemistry; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D046529:Microscopy, Electron, Transmission; D010407:Penicillium; D012834:Silver / Q000737:chemistry*; D013059:Spectrum Analysis, Raman
chemical_list: D012834:Silver; D002953:Citrinin
keywords: Citrinin; Density functional theory calculations; Mycotoxin; Raman spectroscopy; Silver substrates