Teruko Nomura

Characterization of the Physicochemical Properties of the Micelles of Platelet-Activating Factor (C18:0)

The purpose of this study was to clarify the physicochemical properties of the micelles of platelet-activating factor (PAF; C18:0). The critical micelle concentration (CMC) of PAF (C18:0) was determined (0.20 μM) using fluorescence techniques. The fluidity and the micropolarity of the PAF (C18:0) micelle were similar to those of the micelle of stearoyl lysophosphatidylcholine.

A temperature study on critical micellization concentration of the novel platelet-activating factor receptor antagonist E5880 in water by electric conductivity measurements.

To clarify the behavior of the novel platelet-activating factor (PAF) receptor antagonist E5880 in aqueous solution, electric conductivity was measured at different temperatures (every 5°C), ranging from 15°C to 50°C. Critical micellization concentration (CMC) of E5880 was dependent on the temperature; at 30°C, the CMC value was smallest (0.143 mM). Below that temperature, the enthalpy for formation of the micelle (Δ H0m) was positive, and the formation of micelles was endothermic; above that temperature, Δ H0m was negative, and the formation of micelles was exothermic.