Hydration Shells of DPPC Liposomes from the Point of View of Terahertz Time-Domain Spectroscopy

 Penkov, Nikita V., Valery A. Yashin, and Konstantin N. Belosludtsev. "Hydration Shells of DPPC Liposomes from the Point of View of Terahertz Time-Domain Spectroscopy." Applied Spectroscopy (2020): 0003702820949285.

Abstract

Analysis of structural and dynamic properties of water in suspensions of liposomes composed from 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) in three phase states (gel, rippled gel, liquid crystalline phase) by means of terahertz time-domain spectroscopy in 0.3–3.3 THz range was conducted in the current work. Fraction of free water molecules in DPPC liposome suspension was shown to decrease with temperature (compared to the analogous aqueous solution without liposomes), and intermolecular water binding was enhanced. The most crucial changes occur during gel-rippled gel phase transition (pretransition): at temperatures below pretransition point, liposomes alleviate water binding degree, while at temperatures above the transition point, they enhance water binding. This study has demonstrated the high information content of the terahertz time-domain spectroscopy method for exploring the hydration properties of phospholipids in water.

… spectra and refractive index spectra of the substance under investigation were measured at the same time with the help of a TPS Spectra 3000 spectrometer (Teraview, UK) in the range of wavenumber 10–110 cm –1 with the …