Smart nanosensors for early detection of corrosion: Environmental behavior and effects on marine organisms


Corrosion is an environmental and economic global problem. Smart or stimuli-responsive colorimetric nano sensors for maritime coatings have been proposed as an asset to overcome the limitations of the current monitoring techniques by changing color in the presence of triggers associated with the early stages of corrosion. Layered double hydroxides (Zn-Al LDH; Mg-Al LDH) and silica mesoporous nanocapsules (SiNC) were used as precursor nanocarriers of active compounds: hexacyanoferrate ions ([Fe(CN)(6)](3-)) and phenolphthalein (PhPh), respectively. Additionally, the safer-by-design principles were employed to optimize the nanosensors in an ecofriendly perspective (e.g., regular vs. warm-washed SiNC-PhPh; immobilization using different carriers: Zn-Al LDH-[Fe(CN)(6)](3-) vs. Mg-Al LDH-[Fe(CN)(6)](3-)). Therefore, the present study aims to assess the environmental behavior in saltwater and the toxic effects of the nanosensors, their nanocarriers, and the active compounds on the marine microalgae Tetraselmis chuii and the crustacean Artemia salina. Briefly, tested compounds exhibited no acute toxic effects towards A. salina (NOEC = 100 mg/L), apart from SiNC-PhPh (LC50 = 2.96 mg/L) while tested active compounds and nanosensors caused significant growth inhibition on T. chuii (lowest IC50 = 0.40 mg/L for SiNC-PhPh). The effects of [Fe(CN)(6)](3-) were similar regardless of the nanocarrier choice. Regarding SiNC-PhPh, its toxicity can be decreased at least twice by simply reinforcing the nanocapsules washing, which contributes to the removal (at least partially) of the surfactants residues. Thus, implementing safe-by-design strategies in the early stages of research proved to be critical, although further progress is still needed towards the development of truly eco-friendly nanosensors.



subject category

Environmental Sciences & Ecology


Martins, R; Figueiredo, J; Sushkova, A; Wilhelm, M; Tedim, J; Loureiro, S

our authors


This work was developed in the scope of the SMARTAQUA project which is funded by the Foundation for Science and Technology in Portugal (FCT), the Research Council of Norway (RCN-284002), Malta Council for Science and Technology (MCST), and co-funded by European Union's Horizon 2020 research and innovation program under the framework of ERA-NET Cofound MarTERA (Maritime and Marine Technologies for a new Era). The present work also received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No 101007430 through the project COAT4LIFE. Thanks are due to FCT/MCTES for the financial support to CESAM-Centre for Environmental and Marine Studies (UIDP/50017/2020+UIDB/50017/2020+LA/P/0094/2020) and CICECO-Aveiro Institute of Materials (UIDB/50011/2020, UIDP/50011/2020).; R. Martins was hired under the Scientific Employment Stimulus Individual Call (2021.00386. CEECIND; CEECIND/01329/2017), funded by national funds (OE), through FCT. J. Figueiredo was awarded with a grant (BI/UI50/8183/2018) from the research project SMARTAQUA (MARTERA/0004/2017, DYMarTERA, ERA-NET-H2020) and Alesia Sushkova was awarded with a PhD fellowship (2021.07744. BD) from the FCT.

Share this project:

Related Publications

We use cookies for marketing activities and to offer you a better experience. By clicking “Accept Cookies” you agree with our cookie policy. Read about how we use cookies by clicking "Privacy and Cookie Policy".