Diffusion coefficient measurements in microfluidic devices
Diffusion coefficient measurements in microfluidic devices
复制标题
DOI：
10.1016/s0039-9140(01)00602-6
复制
发表时间：
2002-02-11
期刊：
影响因子：
6.1
通讯作者：
Ramsey, JM
中科院分区：
文献类型：
--
作者：
Culbertson, CT;Jacobson, SC;Ramsey, JM
采用罗丹明6 G作为分析物，在微流控装置上比较了四种扩散系数的测量方法。使用静态成像方法和三种动态方法-停止流动、改变施加的电势（电场法）和改变检测长度（长度法）进行测量。在分析物壁相互作用例如，在50/50（v/v）甲醇/水性缓冲液中，停止的流动（吸附）最小化。（2.71 +/- 0.09 x 10（-6）cm（2）s-（1）），e场（2.684 +/- 0.005 x 10（-6）cm（2）s（-1））和静态成像（2.69 +/- 0.02 x 10（-6）cm（2）s（-1））测量值均在彼此和先前报告值的实验误差范围内。然而，在100%含水条件下，动态测量的扩散系数比静态测量的扩散系数大11%。还使用静态成像方法测量罗丹明B、荧光素、2 '，7'二氯荧光素（DCF）、罗丹明6 G、四甲基罗丹明标记的谷氨酸和异亮氨酸以及荧光素缀合的牛血清白蛋白和卵清蛋白的扩散系数。(C)2002 Elsevier Science B. V.保留所有权利。
Four methods for measuring diffusion coefficients were compared on a microfabricated fluidic device using rhodamine 6G as the analyte. The measurements were made using a static imaging method and three dynamic methods -stopped flow, varying the applied potential (E-field method), and varying the detection length (length method). Under conditions where analyte wall interactions (adsorption) are minimized, e.g. in a 50/50 (v/v) methanol/aqueous buffer, the stopped How (2.71 +/- 0.09 x 10(-6) cm(2) s-(1)), E-field (2.684 +/- 0.005 x 10(-6) cm(2) s(-1)) and the static imaging (2.69 +/- 0.02 x 10(-6) cm(2) s(-1)) measurements were all within experimental error of one another and previously reported values. Under 100% aqueous conditions, however, the diffusion coefficient measured dynamically was 11% larger than that measured statically. Diffusion coefficients for rhodamine B, fluorescein, 2',7'dichloro-fluorescein (DCF), rhodamine 6G, tetramethylrhodamine labeled glutamic acid and isoleucine, and fluorescein conjugated bovine serum albumin and ovalbumin were also measured using the static imaging method. (C) 2002 Elsevier Science B.V. All rights reserved.