Complex Liquid Crystal Emulsions for Biosensing

Herein we describe a highly responsive optical biosensor based on dynamic complex liquid crystal (LC) emulsions. These emulsions are simple to prepare and consist of immiscible chiral nematic liquid crystals (N*) and fluorocarbon oils. In this work, we exploit the N* selective reflection to build a new sensing paradigm. Our detection strategy is based on changes in the LC/water interfacial activity of boronic acid polymeric surfactants caused by reversible interactions with IgG antibodies at the LC interface. Such biomolecular recognition events can vary the pitch length of the N* organization due to the presence of binaphthyl units in the polymeric structure, which are known to be powerful chiral dopants. We demonstrate that these interface-triggered reflection changes can be used as an effective optical read-out for the detection of the foodborne pathogen Salmonella.

Automated summary

In this study, a highly responsive optical biosensor based on dynamic complex liquid crystal (LC) emulsions was developed for the detection of the foodborne pathogen Salmonella. The detection strategy relies on changes in the LC/water interfacial activity of boronic acid polymeric surfactants caused by reversible interactions with IgG antibodies at the LC interface. The biomolecular recognition events can vary the pitch length of the N* organization due to the presence of binaphthyl units in the polymeric structure, which are known to be powerful chiral dopants.