Application of pressure perturbation calorimetry to the aqueous system of phospholipid vesicle dispersion

作者：Tamai Nobutake; Nambu Yuko; Tsutsui Maiko; Goto Masaki; Matsuki Hitoshi^*; Kaneshina Shoji

来源：High Pressure Research, 2010, 30(4): 490-498.

DOI：10.1080/08957959.2010.526115

• pressure perturbation calorimetry
• volume change
• apparent molar volume
• bilayer phase transition
• dimyristoylphosphatidylcholine

Pressure perturbation calorimetry (PPC) is a relatively new technique which provides the thermal expansion coefficient 2 of a solute. We give a detailed description on the theoretical background of this technique for a binary solution and a theoretical explanation for the method to estimate the volume change vapp, 2 with a phase transition. In this theory, a reversible isothermal pressure change is assumed, although an irreversible pressure change is applied in the PPC experiment. In order to verify the effect of this inconsistency, we carried out the PPC measurements for the dimyristoylphosphatidylcholine bilayer membrane. The vapp, 2 value with the gel-to-liquid-crystalline transition was estimated at 18.3mlmol-1, which is in agreement with the literature values obtained by other techniques. This indicates that the irreversibility has virtually no effect on the vapp, 2 value and also supports the validity of the method for estimating the vapp, 2 value that we adopted.

• 出版日期2010