在分析微流体装置的热测量技术
Summary
Here, we present three protocols for thermal measurements in microfluidic devices.
Abstract
Thermal measurement techniques have been used for many applications such as thermal characterization of materials and chemical reaction detection. Micromachining techniques allow reduction of the thermal mass of fabricated structures and introduce the possibility to perform high sensitivity thermal measurements in the micro-scale and nano-scale devices. Combining thermal measurement techniques with microfluidic devices allows performing different analytical measurements with low sample consumption and reduced measurement time by integrating the miniaturized system on a single chip. The procedures of thermal measurement techniques for particle detection, material characterization, and chemical detection are introduced in this paper.
Introduction
三个不同的微观尺度的热测量技术呈现在这篇文章。微流体装置的三个不同的配置被用于热粒子检测（TPD），热特性（热导率和比热），和量热检测化学反应和相互作用。
热粒子探测
检测和计数在微流体装置的粒子被广泛用于环境，工业和生物应用1。 TPD是热测量的在微流体装置2的新的应用中的一个。使用传热，用于检测和计数基于所述粒径的粒子降低了复杂性，成本和系统的大小。在其他方法中，复杂的光学或复杂的电气测量和先进的信号处理的软件用于检测颗粒。
热甜心液体物质cterization利用微热量计
液体样品的热特性是热计量的微流体装置的第二个应用程序。执行微尺度量热将降低样品消耗和通过提供更高的重复性相比于常规，散装量热方法提高精度。的程序使用芯片上的微量热设备的热导率和比热测量在别处3呈现。对于热导率测量的热渗透时间技术和热波分析（TWA）为在微流体装置的比热测量的细节在协议部分中描述。
量热生物化工检测纸张为基础的微流控设备
热测量的另一种应用是生化检测在纸基微流体。在毛细作用的纸的多孔结构承载的液体，避免了在微通道气泡引发问题。在纸基微流体装置中最常见的检测机制是光学或电化学技术。光学检测患有高复杂性和先进的图像处理软件的必要性量化检测到的信号。电化学检测也受到限制，因为它们只能被应用到产生活性的副产物的反应。最近推出的量热纸基生化传感器平台4取纸基微流体系统和无标记的热检测机构的优点。量热检测用葡萄糖氧化酶（GOD）酶在纸基微流体平台葡萄糖的程序都在协议部分。
本文的目的是展示在微流体装置的热测量技术的功能。该器件preparatioN，液体样品处理和电阻温度检测器（RTD）传感器激励和测量列于下一个章节。
Protocol
Representative Results
Discussion
Different thermal measurement techniques in microfluidic devices and their respective setup procedures are presented in this work. These thermal measurement methods such as thermal conductivity monitoring, thermal penetration time, amplitude of AC thermal fluctuations, and amplitude measurement of the generated heat are used to detect specific substances and investigate different reactions and interactions.
The thermal time constant plays a key role in the aforementioned thermal measurement t…
Offenlegungen
The authors have nothing to disclose.
Acknowledgements
通过工业/大学合作研究中心的水处理设备和位于威斯康星州密尔沃基（IIP-0968887）和马凯特大学（IIP-0968844）的大学政策提供了由美国国家科学基金会为这项工作的部分资金支持。我们感谢格伦·沃克先生，宇晋Chang和香卡拉达克里希南有益的讨论。
Materials
| Polydimethylsiloxane (PDMS) | Dow Corning | Sylgard 184 | |
| PS beads – 90 um | Corpuscular | 100265 | |
| PS beads – 200 um | Corpuscular | 100271 | |
| Glycerol | SigmaAldrich | G5516 | |
| GOD enzyme | SigmaAldrich | G7141 | |
| Glucose Control Solution-Low | Bayer contour | Low Control | |
| Glucose Control Solution-Normal | Bayer contour | Normal Control | |
| Glucose Control Solution-High | Bayer contour | High Control | |
| Chromatography filter paper | Whatman | 3001-845 | |
| Glass | VWR | 48393-106 | |
| Acrylic Film | Nitto Denko | 5600 | |
| Glass syringe (1 mL) | Hamilton | 1001 | |
| Syringe pump | New Era | NE-500 | |
| knife plotter | Silhouette | portrait | |
| Current Preamplifier | Stanford Research | SR-570 | |
| Ocilloscope | Agilent | DSO 2420A | |
| Signal Generator | HP | HP3324A | |
| Lock-in Amplifire | Stanford Research | SRS-830 | |
| Source/meter 2400 | Keithley | 2400 | |
| Source/meter 2600 | Keithley | 2436A |
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