Compatibility balanced antibacterial modification based on vapor-deposited parylene coatings for biomaterials

Abstract

Advanced antibacterial surfaces are designed based on covalently attached antibacterial agents, avoiding potential side effects associated with overdosed or eluted agents. The technique is widely applicable regardless of the underlying substrate material. In addition, antibacterial surfaces are effective against the early stages of bacterial adhesion and can significantly reduce the formation of biofilm, without compromising biocompatibility. Here, this concept was realized by employing a benzoyl-functionalized parylene coating. The antibacterial agent chlorhexidine was used as a proof of concept. Chlorhexidine was immobilized by reaction with photoactivated benzoyl-functionalized surfaces, including titanium alloy, stainless steel, polyether ether ketone, polymethyl methacrylate, and polystyrene. A low concentration of chlorhexidine (1.4 AE 0.08 nmol cm À2 ) covalently bound to surfaces rendered them sufficiently resistant to an Enterobacter cloacae inoculum and its adherent biofilm. Compared to unmodified surfaces, up to a 30-fold reduction in bacterial attachment was achieved with this coating technology. The immobilization of chlorhexidine was verified with infrared reflection absorption spectroscopy (IRRAS) and X-ray photoelectron spectroscopy (XPS), and a leaching test was performed to confirm that the chlorhexidine molecules were not dislodged. Cell compatibility was examined by culturing fibroblasts and osteoblasts on the modified surfaces, revealing greater than 93% cell viability.This coating technology may be broadly applicable for a wide range of other antibacterial agents and allow the design of new biomaterials.

Construction of Self-defensive Antibacterial and Osteogenic AgNPs/Gentamicin Coatings with Chitosan as Nanovalves for Controlled release

“…Biomaterial-associated infections (BAI) is a widespread and rapidly growing problem 1 – 4 , whereas the traditional treatment with systemic antibiotics is often inefficient due to the formation of bacterial biofilms, in which bacteria are poorly responsive to bactericides 5 – 8 . Therefore, the construction of antibacterial surface to prevent bacterial colonization at early stages is regarded as a crucial pathway to solve BAI problems.…”

Ammonia sensing for enzymatic urea detection using organic field effect transistors and a semipermeable membrane

“…Less stable organic semiconductors might be employable, if parylene derivatives are employed, which facilitate functionalization procedures avoiding plasma activation. 40 Oxygen plasma treated parylene-C surfaces were silanized by 3-aminopropyltriethoxysilane (APTES). Subsequently, glutaraldehyde and urease were bound to this surface.…”

Conjugation of Monocarboxybetaine Molecules on Amino-Poly-p-xylylene Films to Reduce Protein Adsorption and Cell Adhesion

“…Recently, Chang et al determined the tatal weight of PPX coating by using QCM, and then estimated the amount of functional groups. 36 The surface density of functional groups was estimated as 5.30 ± 0.11 nmol/cm 2 . However, the actual density of functional groups on the outmost layer of PPX films should be much lower since PPX coating is not a monolayer.…”