Lipid and protein corona of food-grade TiO2 nanoparticles in simulated gastrointestinal digestion

Abstract

In the presence of biological matrices, engineered nanomaterials, such as TiO 2 , develop a biomolecular corona composed of lipids, proteins, etc. In this study, we analyzed the biocorona formed on the food grade TiO 2 (E171) going through an in vitro simulated gastrointestinal digestion system in either a fasting food model (FFM), a standardized food model (SFM), or a high fat food model (HFFM). Lipids and proteins were extracted from the biocorona and underwent untargeted lipidomic and label-free shotgun proteomic analyses. Our results showed that the biocorona composition was different before and after food digestion. After digestion, more diverse lipids were adsorbed compared to proteins, most of which were the enzymes added to the simulated digestion system. The corona lipid profile was distinct from the digested food model they presented in, although similarity in the lipid profiles between the corona and the food matrix increased with the fat content in the food model. The corona formed in the two low-fat environments of FFM and SFM shared a higher degree of similarity while very different from their corresponding matrix, with some lipid species adsorbed with high enrichment factors, indicating specific interaction with the TiO 2 surface outperforming lipid matrix concentration in determination of corona formation. Formation of the biocorona may have contributed to the reduced oxidative stress as well as toxicological impacts observed in cellular studies. The present work is the first to confirm persistent adsorption of biomolecules could occur on ingested *

Recent Advances in the Gastrointestinal Fate of Organic and Inorganic Nanoparticles in Foods

“…Mucin has been shown to adsorb to the surfaces of food-grade TiO 2 nanoparticles under simulated oral conditions and form a biomolecular corona [ 68 ], which was again mainly attributed to hydrophobic interactions. Other studies have indicated that lipophilic or amphiphilic biomolecules, such as lipids and proteins, can also adsorb to the surfaces of TiO 2 nanoparticles [ 72 ]. In general, it would be expected that a wide variety of surface-active or charged molecules in foods or saliva could bind to the surfaces of TiO 2 nanoparticles within the mouth, but future studies are required to confirm this.…”

“…Organic nanoparticles may also experience changes in their biomolecular corona when exposed to gastrointestinal conditions. For example, mucin, digestive enzymes, and free fatty acids can adsorb to the surfaces of the lipid droplets in nanoemulsions by an amount that depends on the nature of the emulsifiers used [ 72 ]. Studies have also reported that digestive enzymes can form a coating around cationic polymeric nanoparticles, which influenced their uptake by Caco-2 cells [ 82 ].…”

Interaction between ZnO Nanoparticles and Albumin and Its Effect on Cytotoxicity, Cellular Uptake, Intestinal Transport, Toxicokinetics, and Acute Oral Toxicity

“…The role of NP-protein interaction, protein corona, in the immune system was also emphasized [14][15][16][17]. The lipid and protein corona of food additive TiO 2 NP in an in vitro simulated gastrointestinal digestion fluid was demonstrated, which reduced oxidative stress and cytotoxicity in cell lines [18]. Interactions between ZnO NPs and saccharide matrices, such as fructose, glucose, sugar mixture, and acacia honey containing high levels of saccharides, were quantitatively determined in our previous reports [9].…”

Atomistic Molecular Dynamics Simulations of Lipids Near TiO2 Nanosurfaces

“… 19 , 25 , 27 , 31 − 37 It is well accepted that in an organism, a nanoparticle becomes covered by a layer of proteins, lipids, and other organic molecules, 38 which is called protein corona and which determines, in a large extent, the further fate of NP in the organism and potential toxic effects. Coreas et al 32 have studied protein corona formation of TiO 2 NPs in simulated gastrointestinal digestion and shown that lipids dominate the biocorona. Runa et al 27 have reported that TiO 2 NPs bind to the cell surface and oxidize the lipids of the plasma membrane.…”