Presenter: Luke Sean Riley

Faculty Sponsor: Mohamed Amine Gharbi

School: UMass Boston

Research Area: Physics

Session: Poster Session 3, 1:15 PM - 2:00 PM, Auditorium, A57

ABSTRACT

Liquid crystal (LC) biosensors have garnered much interest over recent years due to their high sensitivity, rapid visual changes, and ease of functionalization for detecting specific target molecules.  Amphiphilic molecules such as phospholipids and membrane proteins are important biomarkers for human health, and past studies have shown the effects of amphiphilic molecules at nematic LC interfaces, which have been promising for the possibility of LC biosensors.  However, there is a lack of research on the effects of amphiphilic molecules at smectic LC interfaces.  The smectic phase can create interesting observable defects called focal conic domains (FCDs), unlike the nematic phase, which offers the ability to create quantitative results alongside qualitative ones.  Our experiments involve us using the thermotropic LC, 8CB (4’cyano-4’octylbiphenyl) in its smectic phase and checking its feasibility as a biosensor for amphiphilic molecules.  We checked the response from different concentrations of amphiphilic molecules, such as phosphatidylcholine and cetrimonium bromide (CTAB), and we checked the feasibility of a smectic LC biosensor for each molecule, as well as the lowest detectable concentration.  Our experiments have shown a correlation between the presence of FCDs as a function of concentration and as a function of time of contact at the interface.  contribute to the understanding of molecular interactions at smectic LC interfaces and demonstrate the potential of smectic LC in biosensing applications.