When microfluidic devices go bad - How does fouling occur in microfluidic devices, and what can be done about it?
When microfluidic devices go bad - How does fouling occur in microfluidic devices, and what can be done about it?
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DOI：
10.1021/ac053496h
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发表时间：
2005-11-01
影响因子：
7.4
通讯作者：
Mukhopadhyay, R
中科院分区：
文献类型：
--
作者：
Mukhopadhyay, R
430 A Analytical Chemistry/2005年11月1日制造的装置，用于移动样品的流动类型都可能导致该问题。已经开发了防止表面非特异性吸附的方法，并且针对某些类型的设备存在清洁协议;然而，补救措施往往是特定的，并且通常通过试验和错误来发现。伊利诺伊大学香槟分校的DeborahLeckband说：“这是一个非常复杂的问题，没有灵丹妙药。”研究人员并不总是意识到他们的微型仪器中正在发生污垢。“很多人甚至不知道是否有污垢的问题。他们从来没有在同一个通道中运行过200次检测，”加利福尼亚州利弗莫尔桑迪亚国家实验室的Anup Singh说。“如果你只运行五次检测，那么污染不会使检测看起来那么糟糕，你可以侥幸逃脱。”一些专家说，微流体设备的测试方式可以尝试完全规避污染问题。“研究人员经常使用干净的样品来评估传感器的检测限，其中样品仅包含一到两种污染物，仅此而已，”位于新墨西哥州阿尔伯克基的桑迪亚国家实验室的Darren分支说，“但在现场便携式微传感器的真实的世界中，你没有奢侈品在测试前采集复杂的样品并对其进行清洁。”对于微流体设备，专家们说，更常见的是工业实验室，而不是学术实验室，他们坚持不懈地追求污染问题。这个问题是多方面的，除非意图是从设备中获利，否则绘制污染源和解决方案的动机并不强烈。“如果你要制造一个真实的设备，你想卖给那些希望它可靠工作的人，[污垢]是至关重要的。这就是最强烈的动机所在--达到那个程度，证明你的设备可以存活足够长的时间或各种样品，”Caliper Life Sciences的Josh Molho说。“我们必须考虑（污染），因为如果我们的设备不能可靠地工作，那么就没有人会买它们！”
430 A ANALYTICAL CHEMISTRY/NOVEMBER 1, 2005 device is fabricated, and the type of flow applied to move samples can all contribute to the problem. Methods to prevent nonspecific adsorption to surfaces have been developed, and cleaning protocols exist for certain types of devices; however, the remedies tend to be specific and are usually found by trial and error.“It’s an incredibly complex problem, and there’s no magic bullet,” says Deborah Leckband of the University of Illinois at Urbana–Champaign. Researchers don’t always realize that fouling is occurring in their miniaturized instruments.“A lot of people don’t even know whether there’sa fouling problem. They never run the assay 200 times in the same channel,” says Anup Singh at the Sandia National Laboratories in Livermore, Calif.“If you only run the assay five times, then fouling doesn’t make the assay look that bad, and you can get away with it.” Some experts say that the way in which microfluidic devices are tested can attempt to circumvent fouling issues altogether.“Researchers often evaluate the detection limit of sensors using clean samples, where the sample only contains one to two contaminants in it, and that’s it,” says Darren Branch at the Sandia National Laboratories in Albuquerque, NM “But in the real world of field-portable microsensors, you don’t have the luxury to take [a] complex sample and clean it prior to testing.” With microfluidic devices, experts say that it’s more often the industrial labs, rather than the academic ones, that relentlessly pursue the problem of fouling. The issue is so multifaceted that unless the intention is to make a profit from a device, the motivation to map out the sources and solutions for fouling isn’t overwhelming.“[Fouling] is critical if you’re talking about making a real device that you want to sell to someone who wants it to work reliably. That’s where the strongest motivation is—to go [to] that extent and prove your device will survive long enough or over the variety of samples,” says Josh Molho at Caliper Life Sciences.“We have to look at [fouling] because if our devices don’t work reliably, then no one’s going to buy them!”