Monitoring the Adhesion and Inhibitory Activity of Candida albicans on Poly-l-Lysine Modified Gold Nano-Match Head Arrays

A platform for real-time monitoring and comprehensively studying the adhesion process of microorganisms onto material surfaces as well as their bioactivity on the surface is very helpful to reveal the microbial contamination mechanism on drainage catheters, intravascular stents, and implanted sensors. Herein, a multifunctional sensor based on localized surface plasmon resonance of gold nano-match head arrays (GNMAs) is developed for monitoring the adhesion behavior of microorganisms (such as Candida albicans, i.e., C. albicans) as well as its inhibitory activity. The sensor is fabricated through soft lithography processes using nanopatterned polydimethylsiloxane stamps, and modified with polymers of different charges for investigating the adhesion of C. albicans onto different charged surfaces. The spectroscopic study shows that C. albicans are more favorable to positively charged surfaces than negatively charged ones, which is also proven by the fluorescence images under microscope. Moreover, the authors demonstrate that the GNMA modified with poly-l-lysine (PLL) can effectively kill the adhered C. albicans due to the membrane destruction and the reactive oxygen species induced by PLL. These unique advantages suggest that the sensor is capable as both an antifungal study system and a real-time monitoring platform for antifungal performance evaluation.