Korgel B A, van Zanten J H, Monbouquette H G
Chemical Engineering Department, University of California Los Angeles, 90095-1592, USA.
Biophys J. 1998 Jun;74(6):3264-72. doi: 10.1016/S0006-3495(98)78033-6.
The separation method, flow field-flow fractionation (flow FFF), is coupled on-line with multiangle laser light scattering (MALLS) for simultaneous measurement of the size and concentration of vesicles eluting continuously from the fractionator. These size and concentration data, gathered as a function of elution time, may be used to construct both number- and mass-weighted vesicle size distributions. Unlike most competing, noninvasive methods, this flow FFF/MALLS technique enables measurement of vesicle size distributions without a separate refractive index detector, calibration using particle size standards, or prior assumptions about the shape of the size distribution. Experimentally measured size distributions of vesicles formed by extrusion and detergent removal are non-Gaussian and are fit well by the Weibull distribution. Flow FFF/MALLS reveals that both the extrusion and detergent dialysis vesicle formation methods can yield nearly size monodisperse populations with standard deviations of approximately 8% about the mean diameter. In contrast to the rather low resolution of dynamic light scattering in analyzing bimodal systems, flow FFF/MALLS is shown to resolve vesicle subpopulations that differ by much less than a factor of two in mean size.
分离方法——流场流分级法（flow FFF）与多角度激光光散射（MALLS）在线联用，用于同时测量从分级仪中连续洗脱的囊泡的大小和浓度。这些作为洗脱时间函数收集的大小和浓度数据，可用于构建数量加权和质量加权的囊泡大小分布。与大多数竞争性的非侵入性方法不同，这种流场流分级法/多角度激光光散射（flow FFF/MALLS）技术无需单独的折射率检测器、使用粒度标准进行校准或对大小分布形状进行先验假设，就能测量囊泡大小分布。通过挤压和去除去污剂形成的囊泡的实验测量大小分布是非高斯分布的，并且能很好地拟合威布尔分布。流场流分级法/多角度激光光散射（flow FFF/MALLS）显示，挤压法和去污剂透析法形成囊泡的方法都能产生几乎大小单分散的群体，平均直径的标准偏差约为8%。与动态光散射在分析双峰系统时分辨率相当低形成对比的是，流场流分级法/多角度激光光散射（flow FFF/MALLS）能够分辨平均大小差异远小于两倍的囊泡亚群。
