Effect of DMSO on the Mechanical and Structural Properties of Model and Biological Membranes.

Dimethyl sulfoxide (DMSO) is widely used in a number of biological and biotechnological applications, mainly because of its effects on the cell plasma membrane, but the molecular origins of this action are yet to be fully clarified. In this work, we used two- and three-component synthetic membranes (liposomes) and the plasma membrane of human erythrocytes to investigate the effect of DMSO when added to the membrane-solvating environment. Fourier transform infrared spectroscopy and thermal fluctuation spectroscopy revealed significant differences in the response of the two types of liposome systems to DMSO in terms of the bilayer thermotropic behavior, available free volume of the bilayer, its excess surface area, and bending elasticity.

Free volume and dynamics in a lipid bilayer.

The lateral diffusion of lipids and of small molecules inside a membrane is strictly related to the arrangement of acyl chains and to their mobility. In this study, we use FTIR and time resolved 2D-IR spectroscopic techniques to characterize the structure and dynamics of the hydrophobic region of palmitoyl-oleylphosphatidylcholine/cholesterol vesicles dispersed in water/dimethylsulfoxide solutions. By means of a non-polar probe, hexacarbonyl tungsten, we monitor the distribution of free volumes inside the bilayer and the conformational dynamics of hydrophobic tails in relation to the different compositions of the membrane or the different compositions of the solvent.

Solvation properties of raft-like model membranes.

Dimethyl sulfoxide (DMSO) is a universal water-soluble solvent widely used in many biotechnological and medical applications, such as cells cryopreservation, and for the treatment of different human diseases (e.g. amyloidosis).

Influence of Dimethyl Sulfoxide on the Low-Temperature Behavior of Cholesterol-Loaded Palmitoyl-oleyl-phosphatidylcholine Membranes.

The properties of lipid membranes at low temperature are important for a number of biomedical and biotechnological applications, and the success of these applications depends on understanding the effects of temperature changes on intermolecular lipid-lipid and lipid-water interactions. Here, we use Fourier transform infrared spectroscopy to study lipid suspensions in water/dimethyl sulfoxide (DMSO) solutions in the -60 to 30 °C range. DMSO is a cryopreservative agent of cellular systems, and its action is largely related to its interaction with the lipid membrane, especially in the low-temperature regime.

Glioblastoma single-cell microRaman analysis under stress treatments.

Glioblastoma multiforme (GBM) is the most frequent malignant brain tumor characterized by highly heterogeneous subpopulations. In order to reveal the heterogeneous cell response, single cell analysis is an essential requirement. In this study, optical microscopy and Raman microspectroscopy were used to follow the stress response of U251 single cells adherent on a silicon substrate.