DescriptionLiquid crystals have become increasingly attractive for use in chemical and biological sensing applications, owing to their unique sensitivity of their alignment to the environment coupled with clear optical feedback. A more recent thrust is sensing with chiral nematic liquid crystals (CLCs). These show feedback through strongly reflected colors that are visible without crossed polarizers, potentially more amenable for use in developing sensors for use in the field. Less investigated,
however, is if these colors can be used for more specific sensing purposes, where distinctive colors or patterns identify a specific adsorbed amphiphile or contaminant.
In this work, we present advances in designing CLC droplets as specific sensors. By analyzing the ratios of the intensities of the red, green, and blue color channels, we can distinguish between the identities of different, homologous amphiphilic molecules, creating a “signature” to distinguish between molecules. Coating these droplets with a common surface stabilizing polymer, poly(vinyl
alcohol), allows them to be incorporated into on-chip sensors, where sensing is achieved with simple rehydration of droplets. Lastly, we test these polymer-coated CLC droplets for in vivo sensing, showing they can detect markers within the guts of zebrafish larvae that could distinguish between healthy and unhealthy specimens.
|24 Jul 2022 → 29 Jul 2022
|28th International Liquid Crystal Conference
|Lisboa, Almada, Portugal
- Peering Crystal Ball