Contents lists available at ScienceDirect Colloid and Interface Science Communications journal homepage: www.elsevier.com/locate/colcom An efcient and inexpensive method for functionalizing metallic biomaterials used in orthopedic applications Soria Hamdaoui a,b , Ambroise Lambert a , Haft Khireddine b , Rémy Agniel a , Annelise Cousture c , Régis Coulon d , Olivier Gallet a , Séverine Alfonsi e , Mathilde Hindié a, ⁎ a CY Cergy Paris Université, ERRMECe, F-95000 Cergy, France b Laboratoire de Génie de l'Environnement, Faculté de Technologie, Université de Bejaia, 06000 Bejaia, Algeria c CY Cergy Paris Université, L2MGC, F-95000 Cergy, France d CMS -Boilermaking and Metalwork Company, 03470 Saligny sur Roudon, France e CY Cergy Paris Université, LPPI, F-95000 Cergy, France ARTICLEINFO Keywords: 316 L stainless steel Polypyrrole Electrodeposition Biomaterials Calcium phosphate Steam sterilization STRO-1 + A pre-osteoblasts ABSTRACT Implantations of metallic biomaterials are being carried out more and more frequently due to accident and population aging. Therefore, there is a need for new metallic implants which can combine properties such as durability, biocompatibility and afordability. In this study, multilayer functionalized 316 L stainless steel (SS) supports resistant to steam sterilization were presented. An electropolymerization of pyrrole was performed on SSsupportstoobtainaprotectivelayer.ThispolypyrrolecoatingrenderedSSsurfaceresistanttocorrosion.Then an electrodeposition of Calcium Phosphate (CaP) doped with increasing concentrations of silicon (Si) ranging from 0 to 2 mM was tested to improve support bone integration. The impacts of silicon addition in the CaP coating without or after steam sterilization were analyzed by proflometry, Scanning Electron Microscopy and Fourier Transform Infrared Spectroscopy. These latter revealed that CaP doped with 0.5 mM of Si constituted the optimal support formulation, presenting sterilization resistance and good biocompatibility. 1. Introduction The implantation of orthopedic biomaterials is widely used all around the globe to restore physiological functions. Approximately 70% of the implants used in medicine are metallic biomaterials [1]and are mainly used to repair failed hard tissue. The demand for implants is increasing exponentially as part of the efortstoimprovethelife quality of the aging population. The global market for implants is expected to grow to $115.8 billion by 2020 [2]. The three most implanted metallic biomaterials are titanium alloys, cobalt‑chromium alloys and stainless steel (SS). The 316 L SS is the most widely used alloy mainly for non-permanent implants (e.g. bone plates, screws) and dental surgery [3,4]. Despite 316 L SS having good mechanical properties, good biocompatibility and being inexpensive, this alloy is less used for permanent implantation due to the corrosion induced by the contact with body fuids and the release of toxic ions such as nickel and chromium ions which causes local infammation [5–7]. Among all the SS implants that failed, more than 90% presented corrosion attack [8]. Diferent physical and chemical techniques have been developed to improve SS resistance to corrosion such as plasma immersion ion implantation and deposition [9], surface modifcation of biomedical 316 L SS with zirconium carbonitride coatings [10], dip coating [11], electropolishing and acid dipping [12] or sol-gel spin coating [13]. In this study, the electrodeposition of an electro-con- ductive polymer was chosen to prevent SS corrosion. In the past dec- ades steel surface passivation using conducting polymers such as polyaniline, polypyrrole, and polythiophene has been particularly stu- died and improved [14]. A conducting polymer coating on an implant prevents the release of harmful ions into the body. Furthermore, elec- trodeposition is useful in controlling the chemical composition and thickness of the coating as demonstrated by Martins et al. [15]. De- positions are reproductive even on complex geometry or porous sup- ports and only inexpensive equipment is needed to perform electro- depositions [16,17]. The electro-conductive polymer retained for this study was poly- pyrrole (PPy) because of its high resistance to corrosion and delami- nation [18,19], easy synthesis, high conductivity, good adhesion, and good biocompatibility [20]. PPy hydrophilicity can also be changed by electrochemical reductions and oxidations [21] that allow to modify PPy topography. However, the absence of PPy functional groups able to https://doi.org/10.1016/j.colcom.2020.100282 Received 14 March 2020; Received in revised form 28 May 2020; Accepted 28 May 2020 ⁎ Corresponding author. E-mail address: mathilde.hindie@u-cergy.fr (M. Hindié). Colloid and Interface Science Communications 37 (2020) 100282 2215-0382/ © 2020 Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/BY-NC-ND/4.0/). T