Antimicrobial performance of mesoporous titania thin films: role of pore size, hydrophobicity, and antibiotic release

Abstract

Implant-associated infections are undesirable complications that might arise after implant surgery. If the infection is not prevented, it can lead to tremendous cost, trauma, and even life threatening conditions for the patient. Development of an implant coating loaded with antimicrobial substances would be an effective way to improve the success rate of implants. In this study, the in vitro efficacy of mesoporous titania thin films used as a novel antimicrobial release coating was evaluated. Mesoporous titania thin films with pore diameters of 4, 6, and 7 nm were synthesized using the evaporation-induced self-assembly method. The films were characterized and loaded with antimicrobial agents, including vancomycin, gentamicin, and daptomycin. Staphylococcus aureus and Pseudomonas aeruginosa were used to evaluate their effectiveness toward inhibiting bacterial colonization. Drug loading and delivery were studied using a quartz crystal microbalance with dissipation monitoring, which showed successful loading and release of the antibiotics from the surfaces. Results from counting bacterial colony-forming units showed reduced bacterial adhesion on the drug-loaded films. Interestingly, the presence of the pores alone had a desired effect on bacterial colonization, which can be attributed to the documented nanotopographical effect. In summary, this study provides significant promise for the use of mesoporous titania thin films for reducing implant infections.

Fabrication of Gentamicin-Loaded Hydroxyapatite/Collagen Bone-Like Nanocomposite for Anti-Infection Bone Void Fillers

“…Thus, the decrease in solid HAp/Col particle diameter from 200 µm to 20 µm only increased the specific surface area from 0.013 to 0.13 m 2 /g, and was less than 0.5% against the specific surface area of the HAp/Col powder. On the other hand, adsorption of GNT molecules, less than 1 µm in size [11], on the surface of the HAp/Col powder and/or filling of some pores would be the reason for this decrease. Thus, the size effect was ignored by the effect of GNT adsorption.…”

Coatings as the useful drug delivery system for the prevention of implant-related infections

“…According to the thermodynamic model of microbial adhesion, hydrophobic materials are preferentially colonized by hydrophobic bacteria [ 26 – 28 ]. Consequently, the adhesion properties of different bacteria are affected by the hydrophobicity of the bacterial cell surface [ 29 , 30 ]. Both S. aureus and Methicillin-resistant Staphylococcus aureus (MRSA) which are common bacteria in IRIs are known to prefer hydrophobic surfaces [ 31 , 32 ].…”

Antimicrobial Coatings for Food Contact Surfaces: Legal Framework, Mechanical Properties, and Potential Applications

“…For the sake of simplicity, the illustration shows that the entire coating diffuses. However, cases in which the antimicrobial agent alone diffuses and the coating matrix remains on the substrate have also been reported (Atefyekta et al, 2016;Kazemzadeh-Narbat et al, 2013).…”

“…Porosity is also reported as percentage of the coating total volume corresponding to pores (Liu, Wang, Yang, & Yang, 2008). Better yet, porosity of AMCs can be described with a combination of multiple characterization technique results, such as average pore size and pore surface coverage from scanning electron microscopy (SEM) and transmission electron microscopy (TEM) imaging and pore volume percentage from H 2 O/D 2 O exchange experiments (Atefyekta et al, 2016).…”

“…In the simple release case, the AMC agent depletes faster than the stimulation-sensitive AMC agent, where the active agent is mobile only when certain circumstances are met. Atefyekta et al (2016) developed a highly porous TiO 2 coating on stainless steel in which gentamicin, vancomycin, and daptomycin were embedded to prevent postsurgery infections after the implantation of medical devices. The antimicrobial efficacy was demonstrated against S. aureus and P. aeruginosa.…”