肠胃外脂质乳剂的物理化学特性：哈梅克常数及聚结活化能的测定

Physicochemical characterization of parenteral lipid emulsion: determination of Hamaker constants and activation energy of coalescence.

作者信息

Yamaguchi T, Nishizaki K, Itai S, Hayashi H, Ohshima H

机构信息

Department of Pharmaceutics, Taisho Pharmaceutical Co., Ltd., Saitama, Japan.

出版信息

Pharm Res. 1995 Mar;12(3):342-7. doi: 10.1023/a:1016288031605.

DOI:10.1023/a:1016288031605

PMID:7617518

Abstract

The particle size of lipid emulsion (LE) is changed by flocculation and coalescence. This change in particle size was studied using values obtained for maximum total interaction energy (Vtmax) for flocculation and activation energy for coalescence (E). Vtmax was calculated using DLVO theory, and E was calculated from the rate of increase in particle size in LE. Two LEs (PC99LE and PC70LE) were prepared from lecithins containing 99% and 70% phosphatidylcholine, respectively. The Hamaker constants for PC99LE and PC70LE were found to be 1.4 x 10(-22) J and 3.1 x 10(-21) J, respectively. Vtmax for PC99LE was 4.7 kT at 121 degrees C, and E was 1.5 x 10(-19) J, while Vtmax for PC70LE at 121 degrees C was 151 kT and E was 3.2 x 10(-19) J. These findings suggest that PC99LE readily underwent flocculation and coalescence with increase in particle size, but that the particle size of PC70LE changed little. The degrees of flocculation and coalescence of LE were determined separately using values of Vtmax and E. These parameters are thus quite useful in predicting the stability of LE.

摘要

脂质乳剂（LE）的粒径会因絮凝和聚结而发生变化。利用絮凝的最大总相互作用能（Vtmax）和聚结活化能（E）的数值来研究这种粒径变化。Vtmax根据DLVO理论计算得出，E则根据LE中粒径的增加速率计算得出。分别由含99%和70%磷脂酰胆碱的卵磷脂制备了两种脂质乳剂（PC99LE和PC70LE）。发现PC99LE和PC70LE的哈梅克常数分别为1.4×10（-22）J和3.1×10（-21）J。PC99LE在121℃时的Vtmax为4.7kT，E为1.5×10（-19）J，而PC70LE在121℃时的Vtmax为151kT，E为3.2×10（-19）J。这些发现表明，PC99LE随着粒径增加容易发生絮凝和聚结，但PC70LE的粒径变化很小。利用Vtmax和E的数值分别测定了脂质乳剂的絮凝程度和聚结程度。因此，这些参数在预测脂质乳剂的稳定性方面非常有用。