Strategies for the Immobilization of Bacteriophages on Gold Surfaces Monitored by Surface Plasmon Resonance and Surface Morphology

Abstract

The use of bacteriophages as recognition elements for biosensing techniques has recently provoked much interest. Surface plasmon resonance, scanning electron microscopy, and atomic force microscopy were used for the real-time monitoring of the attachment of methicillin-resistant Staphylococcus aureus (MRSA) bacteriophages to gold using several immobilization methods. The MRSA bacterial capture efficiency of phage-functionalized surfaces was studied. We found that whereas the physisorption of phages to gold surfaces affects their biofunctionality, as expressed by their lysing efficiency of bacteria, phages bound via mixed self-assembled monolayers of L-cysteine and 11mercaptoundecanoic acid permitted both the recognition and disruption of bacterial membranes. This is due to the formation of uniform islands on the gold surfaces, permitting an oriented positioning of the phages, thus better exposing their recognition proteins.

Studies on Lytic, Tailed Bacillus cereus-specific Phage for Use in a Ferromagnetoelastic Biosensor as a Novel Recognition Element

“…Based on these results, our combination of 11-MUA and EDC/NHS provided a better phage density (5.5 ± 0.1 phages/µm 2 ). In addition, our results also partially agreed with Tawil et al's [34] study, which found that the combination of 11-MUA and EDC/ NHS enhanced the phage density (data were not provided) and finally improved the binding of the target, Staphylococcus aureus, onto the sensor surface. Therefore, the combination of 11-MUA and EDC/NHS could be an effective method for the immobilization of B. cereus-specific phages.…”

“…Although the direct adsorption method is popular and has been commonly used for the immobilization of filamentous E2 phage owing to its simplicity and practicality, the relatively weak bindings and poor orientation were problematic on the sensor surface [26,30]. To overcome the limitations of the direct adsorption method, a combination of 11-MUA and EDC/NHS was introduced owing to its recognition as the most efficient immobilization method for phages [34]. In addition, the concentration of the lytic, tailed phage is an important factor not only to allow the appropriate phage orientation with certain distances but also to avoid or minimize phage aggregation.…”

“…2E). Based on our previous experience, the aggregation on the sensor surface could lead to a decrease in the binding efficiency of the phage owing to the steric hindrance and the interaction of neighboring phages tails [31,[34][35][36]. As the tail length (approximately 210-220 nm) of B. cereus-specific phage was relatively longer, it was assumed that the longer tails were more likely to aggregate with each other.…”

Principle and Development of Phage-Based Biosensors

“…Also this methodology suffers due to variability and bacteriophage detachment in turn to the physico-chemical fluctuations in the analyte medium. Covalent bonding of phages offered a more stronger attachment and is not at risk to easy detachment of phages [53,54]. Proper chemical studies can make easy selection of suitable substrate and then potential application.…”

Phage Immobilized Antibacterial Silica Nanoplatform: Application against Bacterial Infections

“…Several studies have been reported regarding immobilization of phages on various substrates such as glass, gold, polytetrafluoroethylene, polyethylene, paper, cellulose, etc. (Anany et al 2011;Pearson et al, 2013;Singh et al, 2009;Yang et al, 2013;Tawil et al, 2013). Also, the number of phages immobilized on a surface can be increased using nanoparticles as it is a well known-fact that as the size of a particle decreases, the ratio of the surface area to the volume of the particle increases, causing a large number of the entities to reside on the surface (Bashar et al, 2013).…”