Candida albicans Can Survive Antifungal Surface Coatings on Surfaces with Microcone Topography

Abstract

This study demonstrates the ability of Candida albicans, a medically significant human fungal pathogen, to minimize contact with an antifungal surface coating that on a flat surface is lethal on contact by growing on and between micron-sized surface topographical features, thus minimizing the contact area. Scanning electron microscopy showed that cells contacting the “floor” between microcones were killed, whereas cells attached to microcones survived and formed hyphal filaments. These spanned space between cones and avoided contact with the flat surface in-between cones. Thus, fungal cells managed to attach and grow despite the antifungal coating. This ability of Candida albicans to exploit topography features to minimize surface contact yet utilize the solid surface for anchoring reduces the effectiveness of the grafted antifungal surface coating. This suggests that biomedical devices with rough surfaces might be more challenging to protect against fungal biofilm formation via application of an antifungal coating.

Comparison of continuous wave and pulsed mode plasma polymerization of glycidol for storage‐stable coatings for biomolecule immobilization

“…Plasma polymer surfaces grafted with caspofungin were tested for antifungal surface activity using a modified static biofilm assay (SBA) on Thermanox substrates. [ 65 ] To elucidate anti‐fungal surface efficacy of caspofungin grafted gly pp coatings, Candida albicans SC5314 biofilms were adhered on cw + caspo and cw + pw + caspo coatings and on control samples that included Thermanox substrates (Thermo Fischer Scientific, Australia), cw and cw + pw gly pp surface coatings. The growth of C. albicans was carried out thrice on Spider media following culture revival from −80°C to ensure full fungal activity.…”

Plasma polymerization for biomedical applications: A review

“…Besides aldehyde plasma polymer coatings, covalent attachment could be facilitated by linking caspofungin's amine groups to epoxide groups present on plasma polymers from continuous and pulsed deposition of allyl glycidyl ether [ 100 ] or glycidol. [ 101 ] The latent reactivity of intact epoxide groups on these plasma polymers allowed for strong covalent bonds to be formed without the need for a second chemical step.…”

Apoptosis of Multi‐Drug Resistant Candida Species on Microstructured Titanium Surfaces

“…In addition, C. albicans cell wall may be too thick for the tip of the microcone silicon surfaces (tip width: 1-10 nm) to penetrate. [37] Valdez-Salas et al demonstrated that Ti nanotubes may disrupt C. albicans nanoadhesion bonds at the biointerface and hypothesized that the surface topography and structural orientation play a crucial role in reducing C. albicans attachment. [38] Herein, in light of the mechano-bactericidal action of nanostructured surfaces, we hypothesize that surface features in the order of microns could apply sufficient me-chanical force to the cell wall of Candida cells to promote cell lysis.…”

“…In addition, C. albicans cell wall may be too thick for the tip of the microcone silicon surfaces (tip width: 1–10 nm) to penetrate. [ 37 ] Valdez‐Salas et al. demonstrated that Ti nanotubes may disrupt C. albicans nanoadhesion bonds at the biointerface and hypothesized that the surface topography and structural orientation play a crucial role in reducing C. albicans attachment.…”