Contents lists available at ScienceDirect Progress in Organic Coatings journal homepage: www.elsevier.com/locate/porgcoat Influence of chitosan on the antibacterial activity of composite coating (PEEK /HAp) fabricated by electrophoretic deposition Makarim H. Abdulkareem a , Alyaa H. Abdalsalam b, ⁎ , Azhar J. Bohan b a Department of Production Engineering and Metallurgy, University of Technology (UOT), 10066 Al Sina'a Street, Baghdad, Iraq b Nanotechnology and Advanced Materials Research Center, University of Technology (UOT), 10066 Al Sina'a Street, Baghdad, Iraq ARTICLE INFO Keywords: PEEK Electrophoretic deposition (EPD) Hydroxyapatite Bioactive materials and antibacterial activity ABSTRACT This study was focused on the effect of chitosan (CH) as a biopolymer for the antibacterial activity and structural characteristics of Polyethetherketone-Nanohydroxyapatite composite coating. Pure Hydroxyapatite and com- posites with three percentage (5, 10 and 20%) of Polyetheretherketone have been deposited on stainless steel 316 L substrates by using electrophoretic deposition technique from ethanol suspensions with presence of chitosan. The stability of the suspensions and the electrostatic interaction among the three types of particles have been measured by zeta potential. The deposited coatings were microstructurally evaluated by scanning electron microscopy and X-ray diffraction. The antibacterial activity test was performed using (N. agar and diffusion methods) against two kinds of bacteria E.coli and S. aureus. SEM photographs showed densified, free cracks composite coating with no need for the sintering treatment. The presence of chitosan played a vital role in the converted the EPD system from hot to cold and acted as a binder between the deposited micro poly- theretherketone and Nanohydroxyapatite particles, finally it enhanced the antibacterial effect of the HAp-CH- PEEK systems deposited against tested microorganisms. 1. Introduction Metals and metal alloys have an important role in a field of bio- materials as fixing or replacement of loadbearing bones that have been damaged. Because of the high percentage of accidents and wars, there was great demands to the implants. Stainless steel 316 L (type of medical grade) is widely used as an implant material in applications of orthopedic due to its excellent mechanical properties, availability at low cost and ease of fabrication, additionally to its good biological, chemical properties and low cost if it compared with other metals im- plants [1,2]. In spite of these features for 316LSS, it has many limitations in applications such as poor susceptibility to corrosion wear resistance, and biocompatibility. Therefore, it was coated by bioceramics materials in order to improve its biological and antimicrobial properties [3]. One of important bioceramic materials is hydroxyapatite Ca 10 (PO 4 ) 6 (OH) 2, which is the major inorganic component of teeth and bone that was widely used for applications biomedical of implants and bone regeneration due to its bioactive, osteoconductive high bioaffi- nity, and biodegradable properties [4,5]. Based on above, there is a great tendency to manipulate methods of coating to develop optimized biomaterials with biocompatibility, super resistance to corrosion, and high bioactivity, i.e. materials exhibiting tissue/bone growth and repair [4]. So using nonmetallic (organic or inorganic) materials such as polymers with no toxicity, biocompatible, high strength, chemically stable, and excellent tribological properties will be good choice to enhance the weakness points of alloys for bio- logical applications [5]. Chitosan is a natural cationic polysaccharide, it has many important properties such as antimicrobial activity, good chemical stability, bio- compatibility, advanced mechanical and other properties which have been utilized in biomedical implants, drug delivery, biosensors, scaf- folds and other biomedical devices [6,7]. Polyether ether ketone (PEEK) has an excellent chemical and me- chanical properties, therefore it is considered to have high performance and a bioinert material, eliciting neither a negative nor positive re- sponse in the body used widely as bone substitute in the orthopedic field, dental implants, provisional abutments nor clamps for removable dental prostheses [6–8]. Numerous studies reported different methods for PEEK coating preparation on metallic substrates using thermal spraying [9], printing [10], and EPD from ethanolic suspensions, as reported by Wang et al. [11,12], Boccaccini et al. [5] and Riccardis et al. [13]. Y. Torres et al. succeeded to produce new bio composite by incorporating PEEK with https://doi.org/10.1016/j.porgcoat.2019.01.050 Received 27 August 2018; Received in revised form 15 December 2018; Accepted 28 January 2019 ⁎ Corresponding author. E-mail address: alyaaalfatlawi@yahoo.com (A.H. Abdalsalam). Progress in Organic Coatings 130 (2019) 251–259 0300-9440/ © 2019 Elsevier B.V. All rights reserved. T