200 / 2024-07-10 18:09:53

Morphological characteristics of DNA molecular liquid crystal formed within a microdroplet

DNA liquid crystal, polarized imaging, mechanism

The liquid crystal of DNA molecule is closely related to the health activities of living organisms, and major diseases such as tumors and cancers. Polarizing microscopy imaging technology is employed to carefully observe a thin film of droplet containing DNA molecules (10bp) and systematically studies the types and phase transition characteristics of DNA liquid crystals which formed within droplets. It is found that when the initial concentration is 0.1 µM or 1 µM, only a small amount of liquid crystal structure was formed near the edge of the droplet, with a shape resembling a dichroic Maltese cross; When the initial concentration is 5 µM, the liquid crystals distribute the entire field of view, and the number of liquid crystals near the edge of the droplet is greater than that in other positions. The liquid crystal structure is mainly a two-color Maltese cross, and liquid crystal sizes range from 22 µm to 104 µm; When the initial concentration is 10 µM, the liquid crystals distribute throughout the field of view, and the number of liquid crystals near the edge of the droplet is greater than that is other positions, and the shape of the liquid crystal is mainly in the form of a dichroic dendritic shape, and colored and dichroic Maltese crosses. The formation and distribution of liquid crystals are mainly due to the coffee ring effect at concentrations of 0.1 µM and 1 µM, where a large number of DNA molecules move to the edge of the droplet, they accumulate and form the liquid crystals; When the concentrations are 5 µM and 10 µM, in addition to the coffee ring effect, there is the Marangoni effect, some DNA molecules deposit and pile up at the center of the droplet, forming a liquid crystal.The research has helpful to an accurate understanding of the mechanism of DNA liquid crystal and contribute to the early diagnosis of tumors and cancers by understanding the structure of DNA liquid crystals at the molecular level.