Liu Robin Hui, Dill Kilian, Fuji H Sho, McShea Andy
CombiMatrix Corp., Mukilteo, WA 98275, USA.
Expert Rev Mol Diagn. 2006 Mar;6(2):253-61. doi: 10.1586/14737159.6.2.253.
A fully integrated and self-contained microfluidic biochip device has been developed to automate the fluidic handling steps required to perform a gene expression study of the human leukemia cell line (K-562). The device consists of a DNA microarray semiconductor chip with 12,000 features and a microfluidic cartridge that consists of microfluidic pumps, mixers, valves, fluid channels and reagent storage chambers. Microarray hybridization and subsequent fluidic handling and reactions (including a number of washing and labeling steps) were performed in this fully automated and miniature device before fluorescent image scanning of the microarray chip. Electrochemical micropumps were integrated in the cartridge to provide pumping of liquid solutions. A micromixing technique based on gas bubbling generated by electrochemical micropumps was developed. Low-cost check valves were implemented in the cartridge to prevent cross-talk of the stored reagents. A single-color transcriptional analysis of K-562 cells with a series of calibration controls (spiked-in controls) was performed to characterize this new platform with regard to sensitivity, specificity and dynamic range. The device detected sample RNAs with a concentration as low as 0.375 pM. Detection was quantitative over more than 3 orders of magnitude. Experiments also demonstrated that chip-to-chip variability was low, indicating that the integrated microfluidic devices eliminate manual fluidic handling steps that can be a significant source of variability in genomic analysis.
一种完全集成且自成体系的微流控生物芯片装置已被开发出来，用于自动化执行人类白血病细胞系（K-562）基因表达研究所需的流体处理步骤。该装置由一个具有12000个特征点的DNA微阵列半导体芯片和一个微流控盒组成，微流控盒包含微流控泵、混合器、阀门、流体通道和试剂储存室。在对微阵列芯片进行荧光图像扫描之前，在这个全自动微型装置中进行微阵列杂交以及后续的流体处理和反应（包括多个洗涤和标记步骤）。电化学微型泵集成在盒中以提供液体溶液的泵送。开发了一种基于电化学微型泵产生的气泡的微混合技术。低成本的止回阀应用于盒中以防止储存试剂的串扰。使用一系列校准对照（加标对照）对K-562细胞进行单色转录分析，以在灵敏度、特异性和动态范围方面表征这个新平台。该装置能够检测低至0.375 pM浓度的样品RNA。检测在超过3个数量级上是定量的。实验还表明芯片间的变异性很低，这表明集成微流控装置消除了手动流体处理步骤，而手动流体处理步骤可能是基因组分析中变异性的一个重要来源。
