Design of Optical Transducer for Recognition of Biomolecular Interactions between Bacterial Lipopolysaccharides and Amino Acids

ABSTRACT Recognition of biomolecular phenomena at interfaces is a key scientific challenge with fundamental and practical importance. In this work, we discover two structurally similar amino acids, glutamic acid (Glu) and aspartic acid (Asp), showing different biological functions, have a significant but distinct orientational coupling with liquid crystals (LCs). Combining experiments with density functional theory calculations, we reveal that Glu and Asp exhibit unique adsorption‐desorption dynamics at the LC‐aqueous interfaces, producing distinct macroscopic optical signals. These interfacial behaviors are specifically governed by pH condition of the aqueous solution because the pH variations cause significant changes in charge states of the amino acids and thus their intermolecular interactions with LCs. Additionally, the dynamics are also modulated by the presence of other biological…