Detection and classification of related lipopolysaccharides via a small array of immobilized antimicrobial peptides

A small array of antimicrobial peptides comprising three cysteine-terminated natural sequences covalently immobilized to pendant surface maleimide groups are used to bind and successfully discriminate five types of lipopolysaccharide (LPS) molecules. Using surface plasmon resonance, LPSs isolated from four strains of Escherichia coli and one strain of Pseudomonas aeruginosa yield distinct binding profiles to the three immobilized peptides. Linear discriminant analysis generated 100% training set and 80% validation set classification success for the 40 samples evaluated. This work demonstrates the discriminatory binding capabilities of immobilized antimicrobial peptides toward LPS molecules and alludes to their use as probes in pathogen sensing devices potentially superior to the current state-of-the-art.