A novel functional micropipette tip for DNA purification, called DNAtip, is described based on a novel coating process. The functional layer is prepared by an internal coating with silica particles supported into a polyvinyl alcohol (PVA) film. The coating layer is stabilized by simultaneous radiation-induced crosslinking to avoid its dissolution. Three types of silica particles of different diameters: micron, sub-micron, and nano sizes are studied. In addition, pH of the coating solution and concentration of the silica particles were optimized. Tips coated with fumed silica showed the highest absorption capacity of a plasmid DNA with an acceptable purity. Different linear dsDNA fragments were used for evaluating the absorption capacity and size discrimination of fragments. The recovery in the range of 700 ng and 200 ng per tip was measured for dsDNA fragments in the range of 400 bp to 2 kbp and 50 bp to 500 bp respectively. DNA PCR fragments contaminated with BSA were successfully purified with sufficient quality to be sequenced or enzymatically digested. This disposable tip device, useful for plasmids or DNA fragments purification, is a novel lab-on-a-tip device, which can effectively improve automate genetic engineering procedures.

一种用于DNA纯化的新型功能性微量移液器吸头，称为DNAtip基于新颖的涂覆工艺进行了描述。该功能层是通过内部涂层制备的，其中二氧化硅颗粒负载在聚乙烯醇（PVA）膜中。涂层通过同时辐射诱导的交联来稳定以避免其溶解。研究了三种不同直径的二氧化硅颗粒：微米，亚微米和纳米尺寸。另外，优化了涂布溶液的pH和二氧化硅颗粒的浓度。涂有气相二氧化硅的针尖显示出具有可接受纯度的质粒DNA的最高吸收能力。不同的线性dsDNA片段用于评估片段的吸收能力和大小区分。对于分别在400 bp至2 kbp和50 bp至500 bp范围内的dsDNA片段，测定的每个末端的回收率分别为700 ng和200 ng。已成功纯化了被BSA污染的DNA PCR片段，其质量足以测序或酶切。这种一次性尖端设备可用于质粒或DNA片段纯化，是一种新型的尖端实验室设备，可有效改善自动化的基因工程程序。