# Antibacterial and Antibiofilm Activity of Titanium Treated with Hybrid Phospholipid Films Containing Carbonate Hydroxyapatite and Silver Nanoparticles

## TL;DR

This study shows that phospholipid films on titanium can reduce bacterial biofilms and support bone growth for dental implants.

## Contribution

A new phospholipid-based coating for titanium is proposed to reduce biofilm formation without compromising osteogenic activity.

## Key findings

- Phospholipid films on titanium reduced biofilm formation and bacterial adhesion.
- Coatings showed good biocompatibility and supported osteoblast-like cell proliferation.
- Silver nanoparticles did not enhance biofilm control but did not hinder the coating's effectiveness.

## Abstract

Bacterial contamination and low osteogenic activity are
the major
causes of dental implant failure. The development of titanium coatings
has provided new research directions to improve both antibacterial
and osteogenic activity. In this study, we constructed phospholipidic
films containing carbonate hydroxyapatite added or not to silver nanoparticles.
The purpose was to reduce the biofilm formation while maintaining
the osteogenic potential of surfaces. Phospholipid monolayers were
transferred to titanium by Langmuir–Blodgett (LB) technique
and resulted in dense, ordered and uniform films. Modified surfaces
were evaluated by X-ray photoelectron spectroscopy, energy-dispersive
spectroscopy, Fourier-transform infrared spectroscopy, and atomic
force microscopy to confirm that films were successfully coated onto
the titanium substrate. In addition, surface free energy and roughness
analyses indicated that surfaces were smooth and hydrophilic. ICP-OES
analysis confirmed the absence of silver nanoparticle lixiviation
from the coatings. Furthermore, the coatings had great biocompatibility
and promoted the proliferation of osteoblast-like cells. Microbiological
findings showed that biofilm formation and bacterial adhesion were
significantly reduced for the experimental coatings; species closely
related to peri-implant diseases and associated with increased biofilm
volume were shown reduced. Addition of silver nanoparticles did not
improve biofilm control. In conclusion, the phospholipidic films proposed
to modify the titanium surfaces are beneficial for osseointegration
and can act as a promising method to reduce the biofilm formation
and bacterial colonization for dental implants.