Purification and concentration of DNA is a critical step on DNA-based analysis, which should ensure efficient DNA isolation and effective removal of contaminants that may interfere with downstream DNA amplification. Complexity of samples, minute content of target analyte, or high DNA fragmentation greatly entangles the success of this step. To overcome this issue, we designed and fabricated a novel miniaturized disposable device for a highly efficient DNA purification. The microfluidic device showed binding efficiency and elution yield of 90.1% and 86.7%, respectively. Moreover, the effect of DNA fragmentation, a parameter that has not been previously addressed, showed a great impact in the recovery step. The microfluidic system integrated micropillars with chitosan being used as the solid-phase for a pH-dependent DNA capture and release. We have showed the potential of the device in the successful purification of environmental DNA (eDNA) from river water samples contaminated with Dreissena polymorpha, an invasive alien species responsible for unquestionable economic and environmental consequences in river water basins. Additionally, the device was also able to concentrate the DNA extract from highly diluted samples, showing promising results for the early detection of such invasive species, which may allow prompt measures for a more efficient control in affected areas. Suitability for integration with downstream DNA analysis was also demonstrated through qPCR analysis of the samples purified with the microfluidic device, allowing detection of the target species even if highly diluted.

DNA的纯化和浓缩是基于DNA的分析的关键步骤，应确保有效的DNA分离和有效去除可能干扰下游DNA扩增的污染物。样品的复杂性，目标分析物的微量含量或高DNA片段化极大地纠缠了此步骤。为了克服这个问题，我们设计并制造了一种新型的微型一次性设备，用于高效DNA纯化。该微流体装置显示出结合效率和洗脱产率分别为90.1％和86.7％。而且，DNA片段化的作用（以前未曾解决过的参数）在回收步骤中显示出巨大的影响。微流体系统将微柱与壳聚糖整合在一起，并用作固相进行pH依赖性DNA的捕获和释放。Dreissena polymorpha，一种入侵外来物种，对河流流域的经济和环境产生了无疑的后果。此外，该设备还能够从高度稀释的样品中浓缩DNA提取物，从而为早期检测此类入侵物种显示出令人鼓舞的结果，这可能有助于迅速采取措施，对受影响地区进行更有效的控制。通过用微流体装置纯化的样品的qPCR分析，也证明了与下游DNA分析整合的适用性，即使高度稀释也可以检测目标物种。