Abstract The vast majority of nanomaterials studied in light of their ability to transmit chirality to or amplify their chirality in a surrounding medium, constitute an achiral core with chirality solely installed at the surface by conjugation or encapsulation with optically active ligands. Here we present the inverse approach focusing on surface‐modified cellulose nanocrystals (CNCs) with core chirality at both the molecular and the morphological level to quantify transmission and amplification of core chirality through space using a host nematic liquid crystal (N‐LC) as reporter. We find that CNCs functionalized at the surface with achiral molecules, structurally related to the N‐LC, exhibit better N‐LC solubility, thereby serving as highly efficient chiral inducers. Moreover, functionalization with chiral molecules only marginally enhances the efficacy of helical distortion in the host N‐LC matrix, indicating the high propensity of CNCs to transfer chirality from an inherently chiral core.
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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.
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- Award ID(s):
- 2146428
- PAR ID:
- 10391566
- Date Published:
- Journal Name:
- Biosensors
- Volume:
- 12
- Issue:
- 5
- ISSN:
- 2079-6374
- Page Range / eLocation ID:
- 313
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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