聚甲基丙烯酸甲酯(PMMA)微流控芯片DNA分析系统的研制

摘要

A DNA analysis device based on poly(methyl methacrylate) (PMMA) microfluidic chips was developed. A PMMA chip with cross microchannels was fabricated by a simple hot embossing. Microchannels were modified with a static adsorptive coating method using 2% hydroxyethyl cellulose. A high-voltage power unit, variable in the range 0-1 800 V, was used for on-chip DNA sample injection and gel electrophoretic separation. High speed, high resolution DNA analysis was obtained with the home-buih PMMA chip in a sieving matrix containing 2% hydroxyethyl cellulose with a blue intercalating dye, TO-PRO-3 (TP3), by using diode laser induced fluorescence detection based on optical fibers with a 670 nm long-pass filter. The DNA analysis device was applied for the separation of ψX-174/HaeⅢ DNA digest sample with 11 fragments ranging from 72 to 1 353 hp. A separation efficiency of 1.14×10~6 plates/m was obtained for the 603 bp fragments, while the R of 271/281 hp fragments was 1.2. The device was characterized by simple design, low cost for fabrication and operation, reusable PMMA chips, and good reproducibility. A portable microfluidic device for DNA analysis can be developed for clinical diagnosis and disease screen-ing.%生物分析是微流控芯片分析最具进一步发展及商品化前景的分支领域之一.报道了基于聚甲基丙烯酸甲酯(PMMA)微流控芯片DNA分析系统的研制.采用简易热压法自制的PMMA芯片,以小型光纤式激光诱导荧光为检测器,以四触点可切换1 800 V高压电源为电驱动系统,以2%羟乙基纤维素(HEC)为筛分介质,通过用于DNA分析的TO-PRO-3荧光染料和激光诱导荧光检测器670 nm截止滤光片的选择,构建了微流控芯片DNA分析系统.芯片凝胶电泳分离ψX174-HaeⅢRF DNA片段,以603 bp片段计算理论塔板数n为1.14×10~6·m~-1,271/281 bp的分离度R为1.2.建立的PMMA微流控芯片DNA分析系统具有制作和运行成本低,芯片可重复使用,分析重现性好等特点.该研究可用于制作微型化便携式DNA分析仪,应用于临床诊断、疾病筛查等领域.