title: Characterization of the Interactions between Titanium Dioxide Nanoparticles and Polymethoxyflavones Using Surface-Enhanced Raman Spectroscopy.
abstract: Nanosized titanium dioxide (TiO2) particles are commonly present in TiO2food additives (E171) and have been associated with potential adverse effects on health. However, little knowledge is available regarding the interactions between TiO2nanoparticles (NPs) and other food components, such as flavonoids. In this study, we aim to study the molecular interactions between TiO2anatase NPs and three structurally closely related polymethoxyflavones (PMFs, flavonoids found in citrus fruits), namely, 3',4'-didemethylnobiletin (DDN), 5-demethylnobiletin (5DN), and 5,3',4'-tridemethylnobiletin (TDN), using ultraviolet-visible (UV-vis) spectrometry and surface-enhanced Raman spectroscopy (SERS). In the UV-vis absorption spectra, bathochromic effects were observed after DDN and TDN conjugated with TiO2NPs. The results from SERS analysis clearly demonstrated that DDN and TDN could bind TiO2NPs with the functional groups 3'-OH and 4'-OH on ring B and formed charge-transfer complexes. However, 5DN with functional groups C═O on ring C and 5-OH on ring A could not bind TiO2NPs. Knowledge on the molecular interactions between TiO2NPs and food components, such as flavonoids, will facilitate the understanding of the fate of TiO2NPs during food processing and in the gastrointestinal tract after oral consumption.
authors.affiliation: Department of Food Science, University of Massachusetts , Amherst, Massachusetts 01003, United States.
authors.forename: Xiaoqiong
authors.initials: X
authors.lastname: Cao
authors.affiliation: Department of Food Science, University of Massachusetts , Amherst, Massachusetts 01003, United States.
authors.forename: Changchu
authors.initials: C
authors.lastname: Ma
authors.affiliation: Department of Food Science, University of Massachusetts , Amherst, Massachusetts 01003, United States.
authors.forename: Zili
authors.initials: Z
authors.lastname: Gao
authors.affiliation: Department of Food Science, University of Massachusetts , Amherst, Massachusetts 01003, United States.|Institute of Agro-Products Processing Science and Technology, Chinese Academy of Agricultural Sciences , Beijing 100193, People's Republic of China.
authors.forename: Jinkai
authors.initials: J
authors.lastname: Zheng
authors.affiliation: Department of Food Science, University of Massachusetts , Amherst, Massachusetts 01003, United States.
authors.forename: Lili
authors.initials: L
authors.lastname: He
authors.affiliation: Department of Food Science, University of Massachusetts , Amherst, Massachusetts 01003, United States.
authors.forename: David Julian
authors.initials: DJ
authors.lastname: McClements
authors.affiliation: Department of Food Science, University of Massachusetts , Amherst, Massachusetts 01003, United States.
authors.forename: Hang
authors.initials: H
authors.lastname: Xiao
mesh_terms: D047309:Flavones / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry*; D013059:Spectrum Analysis, Raman; D014025:Titanium / Q000737:chemistry*
chemical_list: D047309:Flavones; C009495:titanium dioxide; D014025:Titanium
keywords: SERS; flavonoids; interaction; polymethoxyflavones; titanium dioxide nanoparticles