Please cite this article in press as: E. Chibowski, et al., Surface properties of Ti-6Al-4V alloy part III: Biostability of deposited DPPC monolayer and bilayer, Colloids Surf. A: Physicochem. Eng. Aspects (2016), http://dx.doi.org/10.1016/j.colsurfa.2016.06.036 ARTICLE IN PRESS G Model COLSUA-20763; No. of Pages 8 Colloids and Surfaces A: Physicochem. Eng. Aspects xxx (2016) xxx–xxx Contents lists available at ScienceDirect Colloids and Surfaces A: Physicochemical and Engineering Aspects journal homepage: www.elsevier.com/locate/colsurfa Surface properties of Ti-6Al-4V alloy part III: Biostability of deposited DPPC monolayer and bilayer Emil Chibowski ∗ , Yingdi Yan, Aleksandra Szcze´ s Department of Physical Chemistry—Interfacial Phenomena, Faculty of Chemistry, Maria Curie-Sklodowska University, Maria Curie-Sklodowska Sq. 3, 20-031, Lublin, Poland h i g h l i g h t s • Monolayer and bilayer deposited on Ti-6Al-4V by spreading of DPPC solu- tion. • Investigation of the layer stability by 2 h ‘washing up’ in water, phosphate buffer, Triton X-100 solution at tem- perature 37 ◦ C. • The topography changes reflect in the changes of apparent surface free energy of the layers. • Treatment with water causes small changes in the polar (hydrogen bond- ing) interactions, especially in mono- layer. • Significant increase in the hydrogen bonding is observed after Trition X- 100 treatment. g r a p h i c a l a b s t r a c t a r t i c l e i n f o Article history: Received 14 April 2016 Received in revised form 16 June 2016 Accepted 20 June 2016 Available online xxx Keywords: Ti-6A1-4V DPPC mono- and bi- layer films Contact angles Surface free energy Wettability Biostability a b s t r a c t Solid supported lipid layer has been of broad interest for decades. DPPC modified Ti-6Al-4V could be used as dental and orthopedic implants because of excellent mechanical property, corrosive resistance and enhanced biocompatibility. However, to be long time lasting, biostability is also a crucial property of implanted surface. In previous Part I and Part II surface properties of Ti-6Al-4V depending on the surface smoothness (AFM and Profilometry images, wettability) both of bare surface as well with the deposited monolayer and bilayer of DPPC were investigated. In this paper stability of the deposited DPPC layers on Ti-6Al-4V alloy was examined. The plates with the DPPC film were placed in water, phosphate buffer saline, or 1% Triton X-100 solution for 2 h at 37 ◦ C and then dried in a vacuum des- iccator at room temperature over night. Optical profilometer and atomic force microscopy (AFM) were applied to obtain surface topography. From the measured advancing and receding contact angles of water, formamide and diiodomethane, the surface free energy was calculated using Lifshitz-van der Waals/Acid Base (LWAB) and Contact Angle Hysteresis (CAH) approaches. The obtained results exhib- ited significant changes in the surface structure occurring during these treatments. The most drastic changes were observed for the layers treated with Triton X-100, where in the case of DPPC monolayer it might be completely removed from the surface. The changes in topography reflected also in those of the apparent surface free energy, which were the greatest after the contact with Triton where both the surface ∗ Corresponding author. E-mail address: emil.chibowski@umcs.pl (E. Chibowski). http://dx.doi.org/10.1016/j.colsurfa.2016.06.036 0927-7757/© 2016 Elsevier B.V. All rights reserved.