Colloids and Surfaces A: Physicochem. Eng. Aspects 439 (2013) 131–137 Contents lists available at ScienceDirect Colloids and Surfaces A: Physicochemical and Engineering Aspects jo ur nal ho me page: www.elsevier.com/locate/colsurfa Aminodextran-coated potassium niobate (KNbO 3 ) nanocrystals for second harmonic bio-imaging Rachid Ladj a,b,c , Thibaud Magouroux d , Mohamed Eissa a,b,1 , Marc Dubled c , Yannick Mugnier c , Ronan Le Dantec c , Christine Galez c , Jean-Pierre Valour a,b , Hatem Fessi a,b , Abdelhamid Elaissari a,b,∗ a Université de Lyon, F-69622 Lyon, France b Université Lyon 1, Villeurbanne, CNRS, UMR 5007, LAGEP-CPE, 43 Boulevarde 11 Novembre 1918, F-69622 Villeurbanne, France c Université de Savoie, SYMME, BP 80439, 74944, Annecy Le Vieux Cedex, France d GAP Biophotonics, Université de Genève, 22 chemin de Pinchat, CH-1211, Genève 4, Switzerland g r a p h i c a l a b s t r a c t Aminodextran-coated KNbO 3 nanocrystals as optical bio-probes for in vitro second harmonic bio-imaging of non-tumor lung human cells. h i g h l i g h t s ◮ Potassium niobate (KNbO 3 ) nanocrystales have interesting non-linear optical properties. ◮ Aminodextran (AD)-coated KNbO 3 nanoparticles were prepared and characterized. ◮ AD-KNbO 3 nanoparticles were investigated in vitro diagnostic as biomarkers for non-tumour cells. ◮ AD-KNbO 3 nanoparticles were well bounded to non-tumor lung-derived human cells. ◮ AD-KNbO 3 nanoparticles can be used as contrast agents in the bio-imaging domain. a r t i c l e i n f o Article history: Received 29 December 2012 Received in revised form 14 February 2013 Accepted 16 February 2013 Available online 26 February 2013 Keywords: Aminodextran KNbO3 nanocrystals Functionalization a b s t r a c t Potassium niobate (KNbO 3 ) nanocrystals exhibiting good second harmonic generation properties were coated with dextran derivatives containing primary amine groups. The surface modification results from attractive electrostatic interaction between the aminodextran molecules and the negatively charged surface of bare KNbO 3 nanocrystals. To avoid flocculation, a suspension of KNbO 3 nanocrystals was firstly prepared and then added drop-wise to an aqueous solution of aminodextran. The as-prepared hybrid (AD- coated KNbO 3 ) nanoparticles were then characterized by using various techniques including transmission electron microscopy (TEM), infrared analysis (FTIR), dynamic light scattering (DLS) and zeta potential measurements as a function of pH of the dispersion medium. Then, the prepared AD- coated KNbO 3 nanoparticles were evaluated in vitro diagnostic application as biomarker for non-tumor lung-derived ∗ Corresponding author. Tel.: +33 472431841; fax: +33 472431682. E-mail address: elaissari@lagep.univ-lyon1.fr (A. Elaissari). 1 Permanent address: Polymers and Pigments Department, National Research Centre, Dokki, Giza 12622, Egypt. 0927-7757/$ – see front matter © 2013 Published by Elsevier B.V. http://dx.doi.org/10.1016/j.colsurfa.2013.02.025