{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,5]],"date-time":"2026-10-05T08:59:21Z","timestamp":1791190761759,"version":"4.1.0"},"reference-count":49,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2012,3,21]],"date-time":"2012-03-21T00:00:00Z","timestamp":1332288000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Nanoparticles (NPs) are tiny materials used in a wide range of industrial and medical applications. Titanium dioxide (TiO2) is a type of nanoparticle that is widely used in paints, pigments, and cosmetics; however, little is known about the impact of TiO2 on human health and the environment. Therefore, considerable research has focused on characterizing the potential toxicity of nanoparticles such as TiO2 and on understanding the mechanism of TiO2 NP-induced nanotoxicity through the evaluation of biomarkers. Uncoated TiO2 NPs tend to aggregate in aqueous media, and these aggregates decrease cell viability and induce expression of stress-related genes, such as those encoding interleukin-6 (IL-6) and heat shock protein 70B\u2019 (HSP70B\u2019), indicating that TiO2 NPs induce inflammatory and heat shock responses. In order to reduce their toxicity, we conjugated TiO2 NPs with polyethylene glycol (PEG) to eliminate aggregation. Our findings indicate that modifying TiO2 NPs with PEG reduces their cytotoxicity and reduces the induction of stress-related genes. Our results also suggest that TiO2 NP-induced effects on cytotoxicity and gene expression vary depending upon the cell type and surface modification.<\/jats:p>","DOI":"10.3390\/ijms13033703","type":"journal-article","created":{"date-parts":[[2012,3,22]],"date-time":"2012-03-22T19:26:07Z","timestamp":1332444367000},"page":"3703-3717","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":81,"title":["Effect of Polyethylene Glycol Modification of TiO2 Nanoparticles on Cytotoxicity and Gene Expressions in Human Cell Lines"],"prefix":"10.3390","volume":"13","author":[{"given":"Sharmy Saimon","family":"Mano","sequence":"first","affiliation":[{"name":"Cell-Materials Interaction Group, Biomaterials Unit, Nano-Bio Field, International Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science, 1-1, Namiki, Tsukuba, Ibaraki 305-0044, Japan"},{"name":"Graduate School of Advanced Science and Engineering, Waseda University, 3-4-1 Okubo, Shinjuku, Tokyo 169-8555, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Koki","family":"Kanehira","sequence":"additional","affiliation":[{"name":"TOTO Ltd. Research Institute, Nakashima 2-1-1, Kokurakita, Kitakyushu 802-8601, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shuji","family":"Sonezaki","sequence":"additional","affiliation":[{"name":"TOTO Ltd. Research Institute, Nakashima 2-1-1, Kokurakita, Kitakyushu 802-8601, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Akiyoshi","family":"Taniguchi","sequence":"additional","affiliation":[{"name":"Cell-Materials Interaction Group, Biomaterials Unit, Nano-Bio Field, International Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science, 1-1, Namiki, Tsukuba, Ibaraki 305-0044, Japan"},{"name":"Graduate School of Advanced Science and Engineering, Waseda University, 3-4-1 Okubo, Shinjuku, Tokyo 169-8555, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2012,3,21]]},"reference":[{"key":"ref_1","first-page":"316","article-title":"Localizing cellular uptake of nanomaterials in vitro by transmission electron microscopy","volume":"1","author":"Ng","year":"2010","journal-title":"Microsc. Sci. Technol. Appl. 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Anim"}],"container-title":["International Journal of Molecular Sciences"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1422-0067\/13\/3\/3703\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T21:49:28Z","timestamp":1760219368000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1422-0067\/13\/3\/3703"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2012,3,21]]},"references-count":49,"journal-issue":{"issue":"3","published-online":{"date-parts":[[2012,3]]}},"alternative-id":["ijms13033703"],"URL":"https:\/\/doi.org\/10.3390\/ijms13033703","relation":{},"ISSN":["1422-0067"],"issn-type":[{"value":"1422-0067","type":"electronic"}],"subject":[],"published":{"date-parts":[[2012,3,21]]}}}