Chiral Liquid Crystal Microdroplets for Sensing Phospholipid Amphiphiles

Designing simple, sensitive, fast, and inexpensive readout devices to detect biological molecules and biomarkers is crucial for early diagnosis and treatments. Here, we have studied the interaction of the chiral liquid crystal (CLC) and biomolecules at the liquid crystal (LC)-droplet interface. CLC droplets with high and low chirality were prepared using a microfluidic device. We explored the reconfiguration of the CLC molecules confined in droplets in the presence of 1,2-diauroyl-sn-glycero3-phosphatidylcholine (DLPC) phospholipid. Cross-polarized optical microscopy and spectrometry techniques were employed to monitor the effect of droplet size and DLPC concentration on the structural reorganization of the CLC molecules. Our results showed that in the presence of DLPC, the chiral LC droplets transition from planar to homeotropic ordering through a multistage molecular reorientation. However, this reconfiguration process in the low-chirality droplets happened three times faster than in high-chirality ones. Applying spectrometry and image analysis, we found that the change in the chiral droplets' Bragg reflection can be correlated with the CLC-DLPC interactions.

Automated summary

Designing simple, sensitive, fast, and inexpensive readout devices for detecting biological molecules and biomarkers is crucial in early diagnosis and treatments. In this study, we investigated the interaction between chiral liquid crystals (CLC) and biomolecules at the liquid crystal (LC)-droplet interface. We found that the presence of 1,2-diauroyl-sn-glycero3-phosphatidylcholine (DLPC) phospholipid leads to a reconfiguration of the CLC molecules in the droplets, with low-chirality droplets undergoing the process three times faster than high-chirality ones. Spectrometry and image analysis showed that the change in the chiral droplets' Bragg reflection can be correlated with the CLC-DLPC interactions.