Development of Adhesive, Bioactive and Antibacterial Titania Sol-Gel Coating on Titanium Substrate by Dip-Coating Technique

Diana Horkavcová,Eva Jablonská,Quentin Doubet,Gisèle Laure Lecomte-Nana,Aleš Helebrant

doi:10.3390/coatings11020243

Abstract

The sol-gel method provides a wide variety of applications in the medical field. One of these applications is the formation of coatings on the metal implants. The coatings containing specific additive can enhance or improve the existing surface properties of the substrate. In this work, titania sol-gel coatings were doped with two forms of silver (AgNO3, Ag3PO4) and synthetic hydroxyapatite and applied on the titanium samples by dip-coating technique. After drying and slow firing, all coatings were characterized with scanning electron microscopy. Thin coatings were successfully prepared with excellent adhesion to the substrate (measured by ASTM D 3359-2), despite cracks. Coatings containing silver and hydroxyapatite demonstrated a 100% antibacterial effect against Escherichia coli after 24 h. The bioactivity of the coatings containing hydroxyapatite tested in modified simulated body fluid under static-dynamic conditions was confirmed by bone-like hydroxyapatite precipitation. To better understand the interaction of the coatings with simulated body fluid (SBF), changes of Ca2+ and (PO4)3− ions concentrations and pH values were studied.

Highlights

IntroductionTitanium and its alloys are widely used to make hard tissues because of an excellent biocompatibility, good mechanical properties, a low Young’s modulus, a non-magnetic behavior, a good resistance to the corrosion, and a light weight
The titanium is often protected by coatings that can bring the benefits of bioactivity and antibacterial effect [1,2,3,4]
The layers prepared by sol-gel dip-coating technique are known to have excellent adhesive properties [8,9]

Summary

Introduction

Titanium and its alloys are widely used to make hard tissues because of an excellent biocompatibility, good mechanical properties, a low Young’s modulus, a non-magnetic behavior, a good resistance to the corrosion, and a light weight. The sol-gel dip-coating technique is one of the simplest and enables to make homogenous layers, especially on regular samples like rectangular cuboids. It comprises three steps, the first one is the dipping, second is the dwelling, and the last is the withdrawing [5,6]. The layers prepared by sol-gel dip-coating technique are known to have excellent adhesive properties [8,9]

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Discussion

Conclusion