Phase behavior of distearoylphosphatidylethanolamine dispersed in excess gl
ycerol has been examined by differential scanning calorimetry. Transformati
on from lamellar-gel to lamellar crystalline phase was found to take place
at temperatures near 74.9 degreesC upon cooling and near 76.3 degreesC duri
ng heating scans. The transition can also be observed under isothermal cond
itions at temperature in this range. The kinetics of the transformation fro
m lamellar-gel to lamellar-crystal phase was analyzed by the well-known Avr
ami equation. The apparent Avrami exponents were found to be approximately
1.6. The effective dimensionality of the growth pattern can then be set as
1, after taking into account the contribution of nucleation at the examinat
ion temperatures. The activation energy of the phase transition was estimat
ed as approximately 255 kJ mol(-1). The data are discussed in terms of deve
lopment of successful cryoprotective strategies using glycerol. (C) 2001 El
sevier Science B.V. All rights reserved.