Recent progress in the design of carbon nanostructures exhibiting strong multiphoton-excited emission opens new pathways to explore the self-organization of lipids found in living organisms. Phospholipid-based lyotropic myelin figures (MFs) are promising materials as simplified models of biomembranes due to their structural resemblance to a multilamellar sheath insulating the axon. This study demonstrates the possibility of selective labeling of MFs by strongly emitting multicolor phloroglucinol-derived carbon nanodots (PG CNDs). Such dopants are efficiently excited by visible and near-infrared light; therefore, one- and two-photon fluorescence microscopies are incorporated to gain 3D insights into the MFs. Combining nondestructive fluorescence microscopy and spectroscopy techniques along with polarized light microscopy gives details on the stability and morphology of lipidic mesophases. Our findings suggest that PG CNDs can be a viable and simple alternative to conventional fluorescent lipid stains to image biologically relevant phospholipid-based structures.

Exploiting the unique anisotropy and fluidity of liquid crystals (LCs) enables the design of advanced hybrid nanomaterials for photonic applications. The intrinsic long-range order of the LCs matrix can act as a structural template, directing nanoscale dopants into well-defined geometrical configurations and enabling precise control over nanoparticle distribution. Here, we use an inverted hexagonal phase (H2) of sodium bis(2-ethylhexyl) sulfosuccinate (AOT), p-xylene, and a water dispersion of gold nanorods (AuNRs) to fabricate well-ordered nanomaterial assemblies. Scanning transmission electron microscopy of thin films reveals AuNR chains extending up to 30 μm in length with a mean interparticle spacing of about 5 nm and a 2D order parameter S2D = 0.96 ± 0.10. Correlative multiphoton and polarizing microscopy demonstrate a uniform arrangement of AuNRs within the central region of the sample thickness, particularly at the domain boundaries. The performed nanostructural characterization suggests the ordering mechanism and highlights the impact of anchoring forces on nanorod ordering and microstructure formation in the bulk sample.

The 47th German Liquid Crystal Conference (GLCC) was held online from 17 to 19 March 2021. The event was hosted by Ralf Stannarius, Andreas Menzel and Alexey Eremin from Otto von Guericke Universit...

Engineering light-responsive nanoparticles (NPs) with tailored nonlinear optical properties is opening new opportunities in precision biophotonics.