Nanotoxicology, 2012; Early Online, 1–13 © 2012 Informa UK, Ltd. ISSN: 1743-5390 print / 1743-5404 online DOI: 10.3109/17435390.2011.653416 In vitro assessment of engineered nanomaterials using a hepatocyte cell line: cytotoxicity, pro-inflammatory cytokines and functional markers Ali Kermanizadeh 1 , Giulio Pojana 2 , Birgit K Gaiser 1 , Renie Birkedal 3 , Dagmar Bilanicová 2 , Håkan Wallin 3 , Keld Alstrup Jensen 3 , Börje Sellergren 4 , Gary R Hutchison 5 , Antonio Marcomini 2 & Vicki Stone 1 1 Heriot-Watt University, School of Life Sciences, John Muir Building, Edinburgh, UK, 2 Department of Environmental Sciences, Informatics and Statistics, University Ca’ Foscari Venice, Venice, Italy, 3 National Research Centre for the Working Environment, Copenhagen, UK, 4 Institute für Umweltforschung (INFU), Technical University of Dortmund, Dortmund, Germany and 5 Edinburgh Napier University, School of Life, Sport and Social Sciences, Sighthill Campus, Sighthill Court, Edinburgh, UK Abstract Effects on the liver C3A cell line treated with a panel of engineered nanomaterials (NMs) consisting of two zinc oxide particles (ZnO; coated 100 nm and uncoated 130 nm), two multi- walled carbon nanotubes (MWCNTs), one silver (Ag < 20 nm), one 7 nm anatase, two rutile TiO 2 nanoparticles (10 and 94 nm) and two derivatives with positive and negative covalent functionalisation of the 10 nm rutile were evaluated. The silver particles elicited the greatest level of cytotoxicity (24 h LC50 – 2 mg/cm 2 ). The silver was followed by the uncoated ZnO (24 h LC50 – 7.5 mg/cm 2 ) and coated ZnO (24 h LC50 – 15 mg/cm 2 ) particles with respect to cytotoxicity. The ZnO NMs were found to be about 50–60% soluble which could account for their toxicity. By contrast, the Ag was <1% soluble. The LC50 was not attained in the presence of any of the other engineered NMs (up to 80 mg/cm 2 ). All NMs significantly increased IL-8 production. Meanwhile, no significant change in TNF-a, IL-6 or CRP was detected. Urea and albumin production were measured as indicators of hepatic function. These markers were only altered by the coated and uncoated ZnO, which significantly decreased albumin production. Keywords: Liver, inflammation, IL-8, albumin, urea Introduction The rapid expansion of technological, scientific and commer- cial uses of atomic or molecular scale materials, their assem- bly and their unique properties, has led to an escalating interest in the fields of nanoscience and nanotechnology (Maynard et al. 2006). In 2011, there were over 1300 consumer products on the market that claimed to contain elements of nanotechnology (Woodrow Wilson website). However, due to their unique chemical and physical properties, there is concern that some nanomaterials (NMs) could be hazardous for people living and working with these particles (Hoet et al. 2004). The small size of particulate NMs results in high surface area to volume ratio, which potentially offers a greater biological activity per given mass compared with larger-size particles (Oberdorster et al. 2005). In addition to this, the surface reactivity per unit surface area may be even greater at the nanoscale. Conventional risk assessment paradigms require evalua- tion of the potential hazard and exposure (dose). However, in studies of engineered pigments and NMs it has been realised that the results may not be extrapolated due to insufficient or inaccurate physicochemical characterisation of the test materials. Consequently, in particle toxicology detailed information about the specific materials and their behaviour in the test systems may be equally important (Hoet et al. 2004; Sandhiya et al. 2009). Any comprehensive testing of particle toxicity should include information on parameters such as surface area, surface chemistry, size distribution and surface charge (Oberdorster et al. 2005). It is likely that each NM will differ in the levels of toxicity induced and the mechanism by which they exert these adverse effects. Hence, in this study a panel of 10 engineered NMs including suspended Ag, coated and uncoated ZnO, five different TiO 2 NPs (all different sizes or crystal form and/or surface coating) and two multi-walled carbon nano- tubes (MWCNTs) were utilised. The use of such a diverse panel of NMs allowed for comparison of a wide variety of physicochemical characteristics with different biological activity and toxicity. Nanosilver is widely utilised as an additive in various textiles and plastics due to its antimicrobial properties. It is also used for treatment of wounds and burns or as a con- traceptive, as well as being marketed as a water disinfectant (Chen et al. 2008). Since Ag NPs are regularly utilised in water disinfection and food preservation there is a real possibility that such particles may be ingested by humans and therefore Correspondence: Ali Kermanizadeh, Heriot Watt University, School of Life Sciences, John Muir Building, Edinburgh, EH14 4AS, UK. Tel: +0131 4514313. E-mail: Ak435@hw.ac.uk (Received 13 June 2011; accepted 22 December 2011)  Nanotoxicology Downloaded from informahealthcare.com by Prof Vicki Stone on 01/30/13 For personal use only.