Bello M S, Rezzonico R, Righetti P G
Science. 1994 Nov 4;266(5186):773-6. doi: 10.1126/science.266.5186.773.
A method for the fast measurement of the diffusion coefficients of both small and large molecules in thin capillaries is reported. The method relies on Taylor-Aris dispersion theory and uses standard instrumentation for capillary zone electrophoresis. With this equipment, which consists of thin capillaries (50 to 100 micrometers in inner diameter), an injection system, detector ports, and computer data acquisition, a sample plug is pumped through the capillary at known velocity and the peak dispersion coefficient (D()) is measured. With the experimentally measured values of D() and flow velocity, and knowledge of the inner diameter of the capillary, the molecular diffusion coefficient (D) can be rapidly derived. For example, for ovalbumin a D value of 0.759 x 10(-6) square centimeter per second is found versus a tabulated value of 0.776 x 10(-6) square centimeter per second (error, 2 percent). For hemoglobin a D value of 0.676 x 10(-6) square centimeter per second is obtained versus a literature value of 0.690 x 10(-6) square centimeter per second (error, 1.5 percent).
报道了一种快速测量小分子和大分子在细毛细管中扩散系数的方法。该方法基于泰勒-阿里斯扩散理论，并使用毛细管区带电泳的标准仪器。利用这套由细毛细管（内径50至100微米）、进样系统、检测端口和计算机数据采集装置组成的设备，将一个样品塞以已知速度泵入毛细管，并测量峰扩散系数（D()）。根据实验测得的D()值和流速，以及毛细管内径的信息，就可以快速推导出分子扩散系数（D）。例如，对于卵清蛋白，测得的D值为0.759×10⁻⁶平方厘米每秒，而列表值为0.776×10⁻⁶平方厘米每秒（误差为2%）。对于血红蛋白，得到的D值为0.676×10⁻⁶平方厘米每秒，而文献值为0.690×10⁻⁶平方厘米每秒（误差为1.5%）。
