Application of the lag-after-pulsed-separation (LAPS) flow meter to different protein solutions.
Application of the lag-after-pulsed-separation (LAPS) flow meter to different protein solutions.
复制标题
脉冲分离后滞后 (LAPS) 流量计在不同蛋白质溶液中的应用。
DOI：
10.1039/b413808m
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发表时间：
2005
期刊：
影响因子：
--
通讯作者：
Barocas,VictorH
中科院分区：
文献类型：
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作者：
Sengupta,Shramik;Mahmud,Goher;Chiou,DanielJ;Ziaie,Babak;Barocas,VictorH
脉冲分离后的滞后（LAPS）计先前开发用于测量蛋白质溶液的流速。LAPS仪表根据飞行时间原理工作。上游事件（器件一部分中粒子的电泳浓度）在下游被检测（通过交流电阻的变化）。事件发生和检测到事件之间的时间滞后与流体流速成反比。我们展示了LAPS仪表测量含有一个或多个带电生物大分子或颗粒的溶液流速的能力。LAPS仪器的原型用于测量模型蛋白[牛血清白蛋白（BSA），溶菌酶和血红蛋白]以及BSA和溶菌酶的混合物的溶液流速。流速为10-50µl min - 1（平均流速为0.24-1.2 mm s - 1）。当使用单个交流测量时，结果取决于溶液，我们将其归因于蛋白质溶液和交流电极之间的界面。差分模式，其中来自正直流脉冲和负直流脉冲的信号彼此相减，消除了界面效应，导致单一的通用（溶液无关）校准曲线。LAPS仪表可以用作任何微流体系统（如药物输送设备或微反应器阵列）中的非侵入性，无移动部件流量传感器，其中需要测量含有带电物质（如蛋白质或细胞）的溶液或悬浮液的流速。
A lag after pulsed separation (LAPS) meter was previously developed to measure flow rates of protein solutions. The LAPS meter operates on the time-of-flight principle. An upstream event (electrophoretic concentration of the particles in one section of the device) is detected downstream (by change in ac resistance). The time lag between the event and its detection is inversely proportional to the fluid flow rate. We demonstrate the ability of the LAPS meter to measure the flow rate of solutions containing one or more charged biomacromolecules or particles. A prototype of the LAPS meter was used to measure flow rates of solutions of model proteins [bovine serum albumin (BSA), lysozyme and hemoglobin] and mixtures of BSA and lysozyme. Flow rates of 10–50 µl min−1 (average velocities of 0.24–1.2 mm s−1) were measured. When a single ac measurement was used, the results were solution-dependent, which we attribute to the interface between the protein solution and the ac electrodes. A differential mode, in which the signal from a positive and a negative dc pulse were subtracted from each other, eliminated interfacial effects and led to a single universal (solution-independent) calibration curve. The LAPS meter can be used as a non-invasive, no-moving-parts flow sensor in any microfluidic system (such as drug delivery devices or micro-reactor arrays) where one needs to measure the flow rate of a solution or a suspension containing charged species such as proteins or cells.