Interaction between PEG lipid and DSPE/DSPC phospholipids: An insight of PEGylation degree and kinetics of de-PEGylation.

The degree to which liposomes are PEGylated is the feature, which most influences the length of the presence of stealth liposomes in the bloodstream. In order to thoroughly investigate the maximum amount of DSPE-PEG that can be used to stabilize stealth liposomes, these were synthesized at different concentrations of DSPE-PEG and their physicochemical properties were investigated by using differential scanning calorimetry (DSC). The kinetics of PEGylation and de-PEGylation were performed by incubating non-stealth liposomes in a DSPE-PEG suspension at different incubation times, and then analyzing the data using DSC and dynamic light scattering (DLS) techniques.

Calorimetric evidence of interaction of brominated flame retardants with membrane model.

The presence of polybrominated flame retardants in the environment seems to be increasing in the past decade. Considering the toxic effects of these pollutants, it is important evaluating the potential interaction with biological membranes for a risk assessment. In this study low and high brominated biphenyls and biphenyl ethers were used to investigate their interaction with biological membrane models constituted by liposomes, using differential scanning calorimetry (DSC) technique.

Interaction of α-Hexylcinnamaldehyde with a Biomembrane Model: A Possible MDR Reversal Mechanism.

The ability of the naturally derived compound α-hexylcinnamaldehyde (1) to interact with biomembranes and to modulate their permeability has been investigated as a strategy to reverse multidrug resistance (MDR) in cancer cells. Dimyristoylphosphatidylcholine (DMPC) multilamellar vesicles (MLVs) were used as biomembrane models, and differential scanning calorimetry was applied to measure the effect of 1 on the thermotropic behavior of DMPC MLVs. The effect of an aqueous medium or a lipid carrier on the uptake of 1 by the biomembrane was also characterized.

Idebenone loaded solid lipid nanoparticles: calorimetric studies on surfactant and drug loading effects.

In this study we prepared solid lipid nanoparticles (SLN), by the phase inversion temperature (PIT) method, using cetyl palmitate as solid lipid and three different non-ionic emulsifiers of the polyoxyethylene ethers family (ceteth-20, isoceteth-20, oleth-20). These SLN were loaded with different amount of idebenone (IDE), an antioxidant drug useful in the treatment of neurodegenerative diseases and skin oxidative damages. The differential scanning calorimetry (DSC) was employed to evaluate the effects of the different emulsifiers and the different amounts of drug loaded on the thermotropic behavior of SLN and to investigate how the drug was arranged into these nanoparticles.

DSC investigation of the effect of the new sigma ligand PPCC on DMPC lipid membrane.

The new sigma ligand cis-(±)-methyl (1R,2S/1S,2R)-2-[(4-hydroxy-4-phenylpiperidin-1-yl) methyl]-1-(4-methylphenyl) cyclopropanecarboxylate [(±)-PPCC] is a promising tool for the treatment of various diseases. With the aim to investigate the absorption of (±)-PPCC by the cell membranes, in this study we evaluated the influence on thermotropic behavior of membrane model exerted by PPCC both as free base or as oxalic salt. To fulfill this purpose differential scanning calorimetry was used.

Differential scanning calorimetry approach to investigate the transfer of the multitarget opioid analgesic LP1 to biomembrane model.

An emerging approach in pain management is the use of multitarget opioid ligands, owing an improved analgesic effect coupled to a reduced incidence of side effects. With a mu opioid receptor agonist/delta opioid receptor antagonist profile, the benzomorphan-based compound LP1 belongs to multitarget ligands class. Previous in vivo investigations showed that LP1 - subcutaneously administered as oxalate salt - was an antinociceptive agent as potent as morphine with a low tolerance-inducing capability.

Effect of resveratrol-related stilbenoids on biomembrane models.

The interactions of the two resveratrol analogues 2-hydroxy-3,5,3',5'-tetramethoxystilbene (4) and 2-hydroxy-3,5,3',4'-tetramethoxystilbene (5) with model biomembranes were studied. The aim of this investigation was to highlight possible differences in the interactions with such biomembranes related to the minimal structural differences between these isomeric stilbenoids. In particular, different experiments on stilbenoid/biomembrane model systems using both differential scanning calorimetry (DSC) and Langmuir-Blodgett techniques were carried out to evaluate stilbenoid/multilamellar vesicle and stilbenoid/phospholipid monolayer interactions, respectively.

Differential scanning calorimetry as a tool to investigate the transfer of anticancer drugs to biomembrane model.

Different anticancer drugs clinically approved by international regulatory organizations present poor water solubility and low stability after systemic injection. Their administration requires suitable carriers capable of maximizing therapeutic efficacy. Lipid and polymeric nanotherapeutics, particularly liposomes, are widely used to deliver chemotherapeutics in the clinic.

Calorimetric evaluation of interaction and absorption of polychlorinated biphenyls by biomembrane models.

Polychlorinated biphenyls (PCBs) are organic pollutants with lipophilic properties, due to their persistence, they are present in environment at potentially dangerous concentrations for humans health. In this work we investigated the interaction and absorption of 2,4,4'-trichlorobiphenyl (PCB 28), 2,3,3',4,4'-pentachlorobiphenyl (PCB 105) and 2,3,3',4,4',5,5'-eptachlorobiphenyl (PCB 189) with dimyristoylphosphatidylcholine (DMPC) multilamellar vesicles (MLV), chosen as biomembrane models, by differential scanning calorimetry technique (DSC). The obtained results indicate that the tested compounds affected the thermotropic behaviour of MLV to different degree, modifying the phase transition peak and shifting it towards lower temperature.