Summary

与复用电子检测的粒子的空间跟踪微流体平台

Published: March 13, 2017
doi:

Summary

我们证明与结合电阻脉冲感测(RPS)与码分多址(CDMA)的综合表面电极网络的微流体平台,来复用在多个微流体通道的粒子的检测和大小。

Abstract

生物样品的微流体处理典型地涉及以空间分馏基于感兴趣的生物特性的样品在各种力场悬浮颗粒的差动操作。对于要用作化验读数所得的空间分布,微流体装置经常受到需要具有更高的成本和减少的可移植性复杂的仪器显微镜分析。为了解决此限制,我们开发了一种集成电子传感技术用于在微流体芯片上的不同位置的粒子的多重检测。我们的技术,被称为微流控码,结合电阻脉冲感测与码分多址压缩二维空间信息转换成一维的电信号。在本文中,我们介绍了微流控技术CODES的实际演示,检测和大小培养的癌细胞分布在多个微流体通道。如由高速显微镜验证,我们的技术能够准确地分析密集细胞群体的所有电子,而不需要外部的仪器。这样,微流控代码可以潜在地使该非常适合用于生物样品的床边血糖检测低成本集成上实验室的单芯片器件。

Introduction

生物粒子如悬浮在液体中的细胞,细菌或病毒的精确检测和分析是一系列应用1,2,3的极大兴趣。在大小旗鼓相当,微流体器件提供用于此目的的独特优势,如高感光度,柔和的样本处理和控制良好的微环境,4,5,6,7。此外,微流体装置可被设计成采用流体动力学和力场的组合来被动地分馏基于各种属性8,9,10,11,12生物颗粒的异质群体。在这些设备s时,得到的颗粒分布可以用作读出,但空间信息典型地只能通过显微镜,通过其直接连接到一个实验室基础设施限制了微流体装置的实用价值。因此,一个集成的传感器,可以容易地报告粒子的时空映射,因为它们是一个微流体装置上操作,可以潜在地实现低成本,集成上实验室一个芯片装置,其对样品的移动的检测特别有吸引力,资源有限的环境。

薄膜电极已被用作微流体装置集成传感器用于各种应用13,14。电阻脉冲传感(RPS)是小颗粒在微流控通道,因为它直接从电气测量15提供了一个强大的,敏感的,高通量检测机制,整合感应特别有吸引力。在RPS,在一对电极之间的阻抗调制,浸渍在电解液中,作为检测粒子的装置。当粒子穿过的孔,尺寸的粒子的顺序,数目及电流瞬态脉冲的振幅分别用于计数和大小的颗粒。此外,该传感器的几何形状可被设计用光刻分辨率塑造电阻脉冲的波形,以提高灵敏度16,17,18,19或估计在微流体通道20的颗粒的垂直位置。

我们最近推出了可扩展和简单的复用的电阻脉冲传感技术称为微流控编码正交检测由电气传感(微流控代码)21。微码依赖于电阻脉冲传感器的互连网络,每个包含微机械以独特的,可区别的方式来调节传导电极阵列的,以便使多路复用。我们已经专门设计每一个传感器,以产生类似于在码分多路访问中使用的数字码正交的电信号22(CDMA)的电信网络中,从而使各个电阻脉冲传感器信号可以从一个单一的输出波形被唯一恢复,即使信号从不同的传感器干扰。以这种方式,我们的技术压缩颗粒的二维空间信息转换成一维的电信号,允许在一个微流体芯片上的不同位置的粒子的监测,同时保持两个器件和系统级的复杂性降至最低。

在本文中,我们提出了一个详细的协议需要使用微流控技术CODES的实验和计算方法,以及为r从它在模拟生物样品的分析使用具有代表性的结果。使用来自具有四个复用的传感器,例如一原型设备的结果来解释的技术中,我们提供了(1)的微细加工的协议来创建具有微流控码技术,(2)实验装置的说明中,包括微流体装置电子,光学,和流体硬件,(3)的计算机算法,用于解码来自不同传感器的干扰信号,以及(4)从检测和癌细胞中的微流体通道的分析的结果。我们相信,通过详细的协议这里描述,其他研究人员可以申请我们的技术为他们的研究。

Protocol

1.编码电极的设计 注意:图1a示出了微图案化电极的3-D结构。 设计一组四个的7位Gold码进行编码的微流体通道23。 构造两个线性反馈移位寄存器(的LFSR),每个代表本原多项式。 使用的LFSR生成一个优选的一对7-m位-sequences。 循环移位首选对米 -sequences并加入他们MOD 2,产生四种不同的Gold码。 <l…

Representative Results

由分布在四个微流体通道四个传感器微流体码装置, 如图1b所示。在这个系统中,每个微流体通道的横截面被设计为接近的小区的大小,以便(1)的多个细胞不能越过在平行和(2)细胞保持靠近电极提高灵敏度的电极。每个传感器被设计以产生一个唯一的7位的数字码。然后将该装置用的细胞悬浮液进行测试。对应于四个单独的传感器记录,电信号被示出在<s…

Discussion

多个电阻脉冲传感器先前已经掺入微流控芯片28,29,30,31,32。在这些系统中,电阻脉冲传感器要么不多路复用28,29,30,31或它们需要在不同的频率32被驱动…

Disclosures

The authors have nothing to disclose.

Acknowledgements

This work was supported by National Science Foundation Award No. ECCS 1610995. The authors would like to thank the Institute of Electronics and Nanotechnology and the Parker H. Petit Institute for Bioengineering and Bioscience staff for their support in using shared facilities. The authors also would like to thank Chia-Heng Chu for his help in preparing the manuscript.

Materials

98% Sulfuric Acid    BDH Chemicals BDH3074-3.8LP
30% Hydrogen Peroxide   BDH Chemicals BDH7690-3
Trichlorosilane Aldrich Chemistry 235725-100G
NR9-1500PY Negative Photoresist Furuttex
Resist Developer RD6 Furuttex
Acetone BDH Chemicals BDH1101-4LP
SU-8 2015 Negative Photoresist Microchem SU8-2015
SU-8 Developer Microchem Y010200
Polydimethylsiloxane (PDMS) Dow Corning 3097358-1004 Sylgard 184 Silicone Elastomer Kit
Isopropyl Alcohol BDH Chemicals BDH1133-4LP
RPMI 1640 Corning Cellgro 10-040-CV
Fetal Bovine Serum (FBS) Seradigm 1500-050
Penicillin-Streptomycin Amresco K952-100ML
Phosphate-Buffered Saline (PBS) Corning Cellgro 21-040-CM
PHD 22/2000 Syringe Pump Harvard Apparatus 70-2001
HF2LI Lock-in Amplifier Zurich Instrument
HF2TA Current Amplifier Zurich Instrument
Eclipse Ti-U Microscope Nikon Corporation
DS-Fi2 High-Definition Color Camera  Nikon Corporation
v7.3 High-speed Camera Phantom
PCIe-6361 Data Acquisition Board  National Instruments 781050-01
BNC-2120 Shielded Connector Block National Instruments 777960-01 
PX-250 Plasma Treatment System Nordson MARCH 

References

  1. De Roy, K., Clement, L., Thas, O., Wang, Y., Boon, N. Flow cytometry for fast microbial community fingerprinting. Water Res. 46 (3), 907-919 (2012).
  2. Vives-Rego, J., Lebaron, P., Nebe-von Caron, G. Current and future applications of flow cytometry in aquatic microbiology. FEMS Microbiol Rev. 24 (4), 429-448 (2000).
  3. Alvarez-Barrientos, A., Arroyo, J., Cantón, R., Nombela, C., Sánchez-Pérez, M. Applications of flow cytometry to clinical microbiology. Clin Microbiol Rev. 13 (2), 167-195 (2000).
  4. Toner, M., Irimia, D. Blood-on-a-chip. Annu Rev Biomed Eng. 7, 77-103 (2005).
  5. Mehling, M., Tay, S. Microfluidic cell culture. Current Opin Biotech. 25, 95-102 (2014).
  6. Sarioglu, A. F., et al. A microfluidic device for label-free, physical capture of circulating tumor cell clusters. Nat Methods. 12 (7), 685-691 (2015).
  7. Cermak, N., et al. High-throughput measurement of single-cell growth rates using serial microfluidic mass sensor arrays. Nat Biotechnol. , (2016).
  8. Gossett, D., et al. Label-free cell separation and sorting in microfluidic systems. Anal Bioanal Chem. 397 (8), 3249-3267 (2010).
  9. Tsutsui, H., Ho, C. Cell separation by non-inertial force fields in microfluidic systems. Mech Res Commun. 36 (1), 92-103 (2009).
  10. Edwards, T. L., Gale, B. K., Frazier, A. B. A microfabricated thermal field-flow fractionation system. Anal Chem. 74 (6), 1211-1216 (2002).
  11. Wang, M. M., et al. Microfluidic sorting of mammalian cells by optical force switching. Nat Biotechnol. 23 (1), 83-87 (2005).
  12. Shields, C. W., Reyes, C. D., López, G. P. Microfluidic cell sorting: a review of the advances in the separation of cells from debulking to rare cell isolation. Lab Chip. 15 (5), 1230-1249 (2015).
  13. Gawad, S., Schild, L., Renaud, P. Micromachined impedance spectroscopy flow cytometer for cell analysis and particle sizing. Lab Chip. 1 (1), 76-82 (2001).
  14. Haandbæk, N., Bürgel, S. C., Heer, F., Hierlemann, A. Characterization of subcellular morphology of single yeast cells using high frequency microfluidic impedance cytometer. Lab Chip. 14 (2), 369-377 (2014).
  15. Bayley, H., Martin, C. Resistive-pulse sensing-from microbes to molecules. Chem Rev. 100 (7), 2575-2594 (2000).
  16. Polling, D., Deane, S. C., Burcher, M. R., Glasse, C., Reccius, C. H. Coded electrodes for low signal-noise ratio single cell detection in flow-through impedance spectrophy. , 3-7 (2010).
  17. Javanmard, M., Davis, R. W. Coded corrugated microfluidic sidewalls for code division multiplexing. IEEE Sensors J. 13 (5), 1399-1400 (2013).
  18. Balakrishnan, K. R., et al. Node-pore sensing: a robust, high-dynamic range method for detecting biological species. Lab Chip. 13 (7), 1302-1307 (2013).
  19. Emaminejad, S., Talebi, S., Davis, R. W., Javanmard, M. Multielectrode sensing for extraction of signal from noise in impedance cytometry. IEEE Sensors J. 15 (5), 2715-2716 (2015).
  20. Spencer, D., Caselli, F., Bisegna, P., Morgan, H. High accuracy particle analysis using sheathless microfluidic impedance cytometry. Lab Chip. 16 (2016), 2467-2473 (2016).
  21. Liu, R., Wang, N., Kamili, F., Sarioglu, A. Microfluidic CODES: a scalable multiplexed electronic sensor for orthogonal detection of particles in microfluidic channels. Lab Chip. 16 (8), 1350-1357 (2016).
  22. Buehrer, R. Code Division Multiple Access (CDMA). Synthesis Lectures on Communications. 1 (1), 1-192 (2006).
  23. Proakis, J. . Digital Communications. , (1989).
  24. Patel, P., Holtzman, J. Analysis of a simple successive interference cancellation scheme in a DS/CDMA system. IEEE J Sel Areas Commun. 12 (5), 796-807 (1994).
  25. Hui, A., Letaief, K. Successive interference cancellation for multiuser asynchronous DS/CDMA detectors in multipath fading links. IEEE Trans Commun. 46 (3), 384-391 (1998).
  26. Whittle, P. Prediction and regulation by linear least-square methods. J Macroecon. 7 (1), 126 (1985).
  27. Whitesides, G., Ostuni, E., Takayama, S., Jiang, X., Ingber, D. Soft lithography in biology and biochemistry. Annu Rev Biomed Eng. 3 (1), 335-373 (2001).
  28. Zhe, J., Jagtiani, A., Dutta, P., Hu, J., Carletta, J. A micromachined high throughput Coulter counter for bioparticle detection and counting. J Micromech Microeng. 17 (2), 304-313 (2007).
  29. Song, Y., Yang, J., Pan, X., Li, D. High-throughput and sensitive particle counting by a novel microfluidic differential resistive pulse sensor with multidetecting channels and a common reference channel. Electrophoresis. 36 (4), 495-501 (2015).
  30. Watkins, N., et al. Microfluidic CD4+ and CD8+ T lymphocyte counters for point-of-care HIV diagnostics using whole blood. Sci Transl Med. 5 (214), 214ra170 (2013).
  31. Chen, Y., et al. Portable Coulter counter with vertical through-holes for high-throughput applications. Sensor Actuat B-Chem. 213, 375-381 (2015).
  32. Jagtiani, A., Carletta, J., Zhe, J. An impedimetric approach for accurate particle sizing using a microfluidic Coulter counter. J Micromech Microeng. 21 (4), 045036 (2011).
  33. Gold, R. Optimal binary sequences for spread spectrum multiplexing (Corresp). IEEE Trans. Inform. Theory. 13 (4), 619-621 (1967).
  34. Dinan, E., Jabbari, B. Spreading codes for direct sequence CDMA and wideband CDMA cellular networks. IEEE Commun Mag. 36 (9), 48-54 (1998).

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Cite This Article
Wang, N., Liu, R., Sarioglu, A. F. Microfluidic Platform with Multiplexed Electronic Detection for Spatial Tracking of Particles. J. Vis. Exp. (121), e55311, doi:10.3791/55311 (2017).

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