[Ordering of double-stranded DNA molecules in a cholesteric liquid-crystalline phase and in dispersion particles of...

The current notion of the organization of molecules in a cholesteric phase is fairly well substantiated in the case of low-molecular-weight compounds. However, this question is open to discussion in the case of double-stranded nucleic acids. In this work, an attempt to compare the well-known data on the structure of cholesteric phases formed by double-stranded DNA molecules and the results of experimental modeling obtained by the authors has been undertaken. The comparison brings leads to assumption regarding the high probability of the existence of both short-range (positional) and long-range (orientational) order in the arrangement of double-stranded DNA molecules in the liquid crystalline phase. The presence of the orientational order, i.e., the rotation of quasinematic layers of double-stranded DNA molecules through a small angle, determines the formation of a spatially twisted (cholesteric) structure with specific physical and chemical properties. In addition, these results prompt a suggestion on the mode of the ordering of dsDNA molecules in liquid-crystalline dispersion particles and allow these particles to be considered candidate biosensing units.