Poly (hexamethylene biguanide), adsorbed onto Ti‐Al‐V alloys, kills slime‐producing Staphylococci and Pseudomonas aeruginosa without inhibiting SaOs‐2 cell differentiation

Abstract

Antimicrobial coating of implant material with poly(hexamethylene biguanide) hydrochloride (PHMB) may be an eligible method for preventing implant-associated infections. In the present study, an antibacterial effective amount of PHMB is adsorbed on the surface of titanium alloy after simple chemical pretreatment. Either oxidation with 5% H 2 O 2 for 24 hr or processing for 2 hr in 5 M NaOH provides the base for the subsequent formation of a relatively stable self-assembled PHMB layer. Compared with an untreated control group, adsorbed PHMB produces no adverse effects on SaOs-2 cells within 48 hr cell culture, but promotes the initial attachment and spreading of the osteoblasts within 15 min. Specimens were inoculated with slime-producing bacteria to simulate a perioperative infection. Adsorbed PHMB reacts bactericidally against Staphylococcus aureus, Staphylococcus epidermidis, and Pseudomonas aeruginosa after surface contact. Adhered SaOs-2 cells differentiate and produce alkaline phosphatase and deposit calcium within 4 days in a mineralization medium on PHMB-coated Ti6Al4V surfaces, which have been precontaminated with S. epidermidis. The presented procedures provide a simple method for generating biocompatibly and antimicrobially effective implant surfaces that may be clinically important.

TITLE: SALVAGING COCHLEAR IMPLANT AFTER SUSPECTED BIOFILM INFECTION- Our experience

“…We now routinely give a wash of the antimicrobial solution before taking sutures. 7 Common microorganisms isolated and reported are Staphylococcus aureus, Staphylococcus epidermidis and Pseudomonas aeruginosa. 5,6,7 We suspected biofilms in our patients due to the recurrence of infections, despite antibiotic therapy.…”

“…7 Common microorganisms isolated and reported are Staphylococcus aureus, Staphylococcus epidermidis and Pseudomonas aeruginosa. 5,6,7 We suspected biofilms in our patients due to the recurrence of infections, despite antibiotic therapy. Macroscopically, rubbery, poorly vascularized granulomatous tissue is the hallmark of such infections.…”

Improved Adsorption of the Antimicrobial Agent Poly (Hexamethylene) Biguanide on Ti-Al-V Alloys by NaOH Treatment and Impact of Mass Coverage and Contamination on Cytocompatibility

“…With this method, the amount of PHMB adsorption is adjustable by incubation time in the coating solution. After 24 h, a PHMB adsorption of up to 20.9 ± 0.6 µg per test specimen was detected, and after 48 h, equilibrium was reached [9,12]. While the increased hydroxylation enhances PHMB adsorption, it also attracts more volatile hydrocarbons, leading to a fast contamination of the surface.…”

“…As a result, many techniques were investigated to coat and pre-treat implant materials with, e.g., antimicrobial agents. Besides the desired antimicrobial effects, the surface conservation, an improved adhesion and activity of osteoblastic cells, as well as a compatibility towards immune cells for enhanced osseointegration, would be of additional advantage for a desirable implant coating [8][9][10].…”

“…In previous studies by Müller et al and Hornschuh et al, the surface of Ti6Al4V alloy material was modified by oxidation with H 2 O 2 and pre-treatment with NaOH, respectively, following adsorption of PHMB to the surface by incubation in aqueous solution [8,9,12]. Müller et al stated that a hydroxylated surface is necessary for PHMB absorption, as a simple cleaning of the surface without the generation of extra binding sites did not result in stronger PHMB binding [8].…”