A novel silica nanotube reinforced ionic incorporated hydroxyapatite composite coating on polypyrrole coated 316L SS for implant application

• Published in: Materials Science & Engineering C 2016-02, Vol.59, p.1110-1124
• Main Authors: Prem Ananth, K., Joseph Nathanael, A., Jose, Sujin P., Oh, Tae Hwan, Mangalaraj, D.
• Format: Article
• Language: English
• Subjects: 316L SS; Austenitic stainless steels; Biocompatibility; Cell Adhesion - drug effects; Cell Line, Tumor; Cell Survival - drug effects; Coated Materials, Biocompatible - chemistry; Coated Materials, Biocompatible - toxicity; Coating; Composite coatings; Corrosion; Corrosion protection; Corrosion resistance; Durapatite - chemistry; Durapatite - pharmacology; Emission analysis; Heat resistant steels; Humans; Hydrophobic and Hydrophilic Interactions; Hydroxyapatite; Inductively coupled plasma; Ionic Substitution; Materials Testing; Nanotubes - chemistry; Nanotubes - toxicity; Osteoblasts - drug effects; Polymers - chemistry; Polymers - toxicity; Polypyrrole; Polypyrroles; Prostheses and Implants; Pyrroles - chemistry; Pyrroles - toxicity; Silica nanotube; Silicon Dioxide - chemistry; Silicon Dioxide - toxicity
• ISSN: 0928-4931; 1873-0191
• DOI: 10.1016/j.msec.2015.10.045

An attempt has been made to deposit a novel smart ion (Sr, Zn, Mg) substituted hydroxyapatite (I-HAp) and silica nanotube (SiNTs) composite coatings on polypyrrole (PPy) coated surgical grade 316L stainless steel (316L SS) to improve its biocompatibility and corrosion resistance. The I-HAp/SiNTS/PPy bilayer coating on 316L SS was prepared by electrophoretic deposition technique. Potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) studies were carried out. These results confirmed the significant improvement of the corrosion resistance of the 316L SS alloy by the I-HAp/SiNTs/PPy bilayer composite coating. The adhesion strength and hardness test confirmed the anticipated mechanical properties of the composite. A low contact angle value revealed the hydrophilic nature. Inductively coupled plasma-atomic emission spectroscopy (ICP-AES) was used for the leach out analysis of the samples. Added to this, the bioactivity of the composite was analyzed by observing the apatite formation in the SBF solution for 7, 14, 21 and 28days of incubation. An enhancement of in vitro osteoblast attachment and cell viability was observed, which could lead to the optimistic orthopedic and dental applications. [Display omitted] •Polypyrrole (PPy) coated 316L SS substrates were fabricated using electrodeposition method.•A novel silica nanotube (SiNTs) and ionic substituted (Sr, Zn, Mg) hydroxyapatite composite (I-HAp) were prepared.•The composite (I-HAp/SiNTs) was coated on PPy coated 316L SS substrate using electrophoretic deposition.•These results are favorable for corrosion resistance and enhanced osteoblast cell attachment for bone formation.