Previous work has shown that DNA hybridization can be detected at an aqueous-liquid crystal interface by observing the alignment of liquid crystal molecules. This serves as a platform for label-free nucleic acid-based biosensors. One design challenge in this model is non-specific adsorption of proteins at the interface, preventing detection of the target analyte in complex media. To create a more protein resistant sensor, phospholipids functionalized with a polyethylene glycol (PEG) headgroup were incorporated at the LC-aqueous interface. Results show the size of the PEG headgroup affects LC alignment; with long chain PEG groups (n = 1000) creating planar orientation of the LC. Further experiments with linear PEG2000 polymer suggest that surfactant/polymer interactions interfere with the dynamics of the system, causing LC realignment. However, phospholipids functionalized with short PEG moieties (n = 350) will not perturb the interface, resulting in homeotropic LC orientation. Incorporation of these PEG350 phospholipids at the interface has also shown an increase in protein resistance.

Protein resistant interfaces for liquid crystal biosensors

247th National Meeting (2014)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.