Study of the Attachment of Pseudomonas aeruginosa on Gold and Modified Gold Surfaces Using Surface Plasmon Resonance

This paper describes how the technique of surface plasmon resonance (SPR) can be utilized to follow (in real time) the attachment of Pseudomonas aeruginosa bacteria on bare gold and gold modified with a self-assembled monolayer (SAM) of mercaptounadecanoic acid. We show that SPR is able to discriminate between the adsorption of live versus dead (thermally shocked) bacteria. Moreover, the SPR distinguishes between the adsorption of wild-type versus mutant bacteria (single gene knockouts), the concentration of the bacterial suspension, and between bacteria adsorbing on SAM-modified and bare gold. SPR is able to measure bacterial adsorption within seconds of the bacterial suspension being introduced. Finally, a qualitative correlation between results from SPR with a crystal violet staining assay for different mutant bacteria was observed.