Temperature Induced Crystallization Transition in Aqueous Solutions of β-Cyclodextrin, Heptakis(2,6-di-O-methyl)-β-cyclodextrin (DIMEB), and Heptakis(2,3,6-tri-O-methyl)-β-cyclodextrin (TRIMEB) Studied by Differential Scanning Calorimetry

Langmuir ◽  
2002 ◽  
Vol 18 (16) ◽  
pp. 5974-5976 ◽  
Author(s):  
Joachim Frank ◽  
Josef F. Holzwarth ◽  
Wolfram Saenger
Keyword(s):  
Differential Scanning Calorimetry ◽  
Aqueous Solutions ◽  
Scanning Calorimetry ◽  
Induced Crystallization

scholarly journals Thermal Analyses of Polyol-Aqueous Solutions below 0.DEG.C. by Differential Scanning Calorimetry.

1997 ◽  
Vol 44 (5) ◽  
pp. 380-385 ◽  
Author(s):  
Tatsuya URAJI ◽  
Hiroyuki KOHNO ◽  
Kyoko NAKASHIMA ◽  
Makoto SHIMOYAMADA ◽  
Kenji WATANABE
Keyword(s):  
Differential Scanning Calorimetry ◽  
Aqueous Solutions ◽  
Thermal Analyses ◽  
Scanning Calorimetry

Thermodynamics of lipid–proiein associations: the enthalpy of binding of Apo C-III to synthetic phosphatidylcholines

1981 ◽  
Vol 59 (8) ◽  
pp. 700-708 ◽  
Author(s):  
Henry J. Pownall ◽  
John B. Massey ◽  
Fu-Juan Hsu ◽  
Antonio M. Gotto Jr.
Keyword(s):  
Differential Scanning Calorimetry ◽  
Gel Filtration ◽  
Scanning Calorimetry ◽  
Very Low Density Lipoproteins ◽  
Dipalmitoyl Phosphatidylcholine ◽  
High Enthalpy ◽  
Dimyristoyl Phosphatidylcholine ◽  
Acyl Chains ◽  
Induced Crystallization ◽  
Enthalpy Of Association

The association of synthetic phosphatidylcholines with apolipoprotein (apo) C-III, an apoprotein from human plasma very low density lipoproteins, has been studied by gel filtration, microcalorimetry, and differential scanning calorimetry. Apo C-III associates with a minimum of 35 molecules of dimyristoyl phosphatidylcholine (DMPC) and can accommodate up to 100 molecules of DMPC per apo C-III molecule. These complexes are readily isolated by chromatography on Sepharose CL-4B. Microcalcrimetry of apo C-III with DMPC or dipalmitoyl phosphatidylcholine (DPPC) vesicles reveals a high enthalpy of association of apo C-III with DMPC (−250 kcal∙mol apo C-III−1) and DPPC (−490 kcal∙mol apo C-III−1); these values translate into 2.8 and 4.65 kcal∙mol lipid−1, respectively. These high enthalpy values are observed only near the transition temperatures (Tc) of the lipids. Above and below Tc the enthalpy of association was practically zero. Differential scanning calorimetry of DMPC –apo C-III complexes shows them to be composed of 35–60 mol lipid∙mol apo C-III−1 in which no more than 45 molecules of DMPC form a boundary around apo C-III. It is shown that the effect of apo C-III on the thermal properties of DMPC is to elevate the Tc of the lipid and that an important component of the enthalpy of association of apo C-III with DMPC is due to the crystallization of the lipid acyl chains. Since the enthalpy of association is a term in the free energy of association, we suggest that the apo C-III induced crystallization of DMPC is important in the thermodynamics of this lipid–protein association. Generally, the sign and magnitude of the enthalpies of association should be important in predicting the distribution of lipids and proteins in more complex systems.

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