Next Article in Journal
Evaluating the Association between Diabetes, Cognitive Decline and Dementia
Next Article in Special Issue
Inventory of Engineered Nanoparticle-Containing Consumer Products Available in the Singapore Retail Market and Likelihood of Release into the Aquatic Environment
Previous Article in Journal
Assessing the Variability of Heavy Metal Concentrations in Liquid-Solid Two-Phase and Related Environmental Risks in the Weihe River of Shaanxi Province, China
Previous Article in Special Issue
Application of Multi-Species Microbial Bioassay to Assess the Effects of Engineered Nanoparticles in the Aquatic Environment: Potential of a Luminous Microbial Array for Toxicity Risk Assessment (LumiMARA) on Testing for Surface-Coated Silver Nanoparticles
Article Menu

Export Article

Open AccessArticle
Int. J. Environ. Res. Public Health 2015, 12(7), 8263-8280;

Cobalt Oxide Nanoparticles: Behavior towards Intact and Impaired Human Skin and Keratinocytes Toxicity

Clinical Unit of Occupational Medicine, Department of Medical Sciences, University of Trieste, Via della Pietà, Trieste 19-34129, Italy
Department of Chemical and Pharmaceutical Sciences, University of Trieste, Via Giorgeri 2, Trieste 1-34127, Italy
Department of Life Sciences, University of Trieste, Via L. Giorgeri 7/9, Trieste 34127, Italy
Dipartimento di Specialità Medico Chirurgiche, Scienze Radiologiche, Sanità Pubblica, University of Brescia, Piazza del Mercato, Brescia 15-25121, Italy
IMEM-CNR Institute, Parco Area delle Scienze 37/A, Parma 43124, Italy
Author to whom correspondence should be addressed.
These authors contributed equally to this work.
Academic Editor: Mónica Amorim
Received: 31 May 2015 / Revised: 7 July 2015 / Accepted: 8 July 2015 / Published: 17 July 2015
(This article belongs to the Special Issue Environmental Fate and Effect of Nanoparticles and Nanomaterials)
Full-Text   |   PDF [2148 KB, uploaded 17 July 2015]   |  


Skin absorption and toxicity on keratinocytes of cobalt oxide nanoparticles (Co3O4NPs) have been investigated. Co3O4NPs are commonly used in industrial products and biomedicine. There is evidence that these nanoparticles can cause membrane damage and genotoxicity in vitro, but no data are available on their skin absorption and cytotoxicity on keratinocytes. Two independent 24 h in vitro experiments were performed using Franz diffusion cells, using intact (experiment 1) and needle-abraded human skin (experiment 2). Co3O4NPs at a concentration of 1000 mg/L in physiological solution were used as donor phase. Cobalt content was evaluated by Inductively Coupled–Mass Spectroscopy. Co permeation through the skin was demonstrated after 24 h only when damaged skin protocol was used (57 ± 38 ng·cm−2), while no significant differences were shown between blank cells (0.92 ± 0.03 ng cm−2) and those with intact skin (1.08 ± 0.20 ng·cm−2). To further investigate Co3O4NPs toxicity, human-derived HaCaT keratinocytes were exposed to Co3O4NPs and cytotoxicity evaluated by MTT, Alamarblue® and propidium iodide (PI) uptake assays. The results indicate that a long exposure time (i.e., seven days) was necessary to induce a concentration-dependent cell viability reduction (EC50 values: 1.3 × 10−4 M, 95% CL = 0.8–1.9 × 10−4 M, MTT essay; 3.7 × 10−5 M, 95% CI = 2.2–6.1 × 10−5 M, AlamarBlue® assay) that seems to be associated to necrotic events (EC50 value: 1.3 × 10−4 M, 95% CL = 0.9–1.9 × 10−4 M, PI assay). This study demonstrated that Co3O4NPs can penetrate only damaged skin and is cytotoxic for HaCat cells after long term exposure. View Full-Text
Keywords: cobalt oxide; nanoparticles; in vitro; human skin absorption; keratinocytes toxicity cobalt oxide; nanoparticles; in vitro; human skin absorption; keratinocytes toxicity

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).

Share & Cite This Article

MDPI and ACS Style

Mauro, M.; Crosera, M.; Pelin, M.; Florio, C.; Bellomo, F.; Adami, G.; Apostoli, P.; De Palma, G.; Bovenzi, M.; Campanini, M.; Filon, F.L. Cobalt Oxide Nanoparticles: Behavior towards Intact and Impaired Human Skin and Keratinocytes Toxicity. Int. J. Environ. Res. Public Health 2015, 12, 8263-8280.

Show more citation formats Show less citations formats

Related Articles

Article Metrics

Article Access Statistics



[Return to top]
Int. J. Environ. Res. Public Health EISSN 1660-4601 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top