胆固醇 - 胆甾烷醇 - 二水合物晶体的差示扫描量热法（DSC）、X射线和核磁共振特性

DSC, X-ray and NMR properties of cholesterol-cholestanol-dihydrate crystals.

作者信息

Hirsch D, Azoury R, Sarig S

机构信息

Casali Institute of Applied Chemistry, Hebrew University, Jerusalem, Israel.

出版信息

Clin Chim Acta. 1988 May 13;174(1):55-64. doi: 10.1016/0009-8981(88)90366-x.

DOI:10.1016/0009-8981(88)90366-x

PMID:3133139

Abstract

The melting point, X-ray diffraction and longitudinal relaxation time (T1) of cholesterol-cholestanol-dihydrate crystals (CC2W) were studied in an effort to produce new experimental data related to atherosclerotic plaques. The crystals were precipitated from ethanolic solutions at several cholesterol: cholestanol (CS:CN) ratios. The melting point of CC2W crystals obtained at the CS:CN ratio 75:25, 50:50, 25:75 was 122-124 degrees C. The X-ray patterns recorded from these crystals of the same CN:CS ratios showed two additional diffraction peaks, as compared to those of CN and CS patterns. On the other hand, the values of T1 relaxation time measured by proton magnetic resonance were different for every CS:CN ratio for the various solution compositions. This latter method seems to be more precise for the detection of the presence of coprecipitated components in the CC2W mixed crystals than X-ray or thermal analysis. The results suggest that CN and CS do not have to be present in equimolar quantities in order for CC2W crystals to be formed. The presence of CC2W in the blood may have significance in the nucleation of cholesterol crystals in atherosclerotic plaques.

摘要

为了获得与动脉粥样硬化斑块相关的新实验数据，对胆固醇 - 胆甾烷醇二水合物晶体（CC2W）的熔点、X射线衍射和纵向弛豫时间（T1）进行了研究。晶体是从乙醇溶液中以几种胆固醇：胆甾烷醇（CS：CN）比例沉淀出来的。在CS：CN比例为75：25、50：50、25：75时获得的CC2W晶体的熔点为122 - 124摄氏度。与CN和CS图案相比，从相同CN：CS比例的这些晶体记录的X射线图案显示出两个额外的衍射峰。另一方面，对于各种溶液组成，通过质子磁共振测量的T1弛豫时间值在每个CS：CN比例下都不同。后一种方法对于检测CC2W混合晶体中共沉淀成分的存在似乎比X射线或热分析更精确。结果表明，为了形成CC2W晶体，CN和CS不必以等摩尔量存在。血液中CC2W的存在可能对动脉粥样硬化斑块中胆固醇晶体的成核具有重要意义。