New in-Situ Method for On-chip DNA Oligomer Synthesis

近年来，DNA阵列在众多应用中的应用迅速扩大。这些阵列主要是使用不发光的配体作为阵列形式的封闭基团，或者通过从生物体或DNA合成器中寻找DNA来制造的。我们提出了一种芯片上高密度的DNA低聚物生长方法，该方法将在专有芯片设计上使用标准的亚磷酸盐化学。这项技术的关键将是一种芯片，它包含一组使用硅微制造技术直接微机械加工成硅晶片的&lt；500um栅格区。网格区域是通过湿法化学蚀刻方法制造的微网格，其网格单元大小可从10-100微米选择。生长中的寡核苷酸附着在栅格的二氧化硅表面。该栅格阵列被放置在第二片晶片上，该晶片具有与微网格区对准并位于其下方的500um孔。DNA合成器通过流动试剂通过固定载体强制完成平衡，并彻底清洗每个样本的能力在此芯片上复制，方法是将核苷酸合成化学品放置在网状物上，然后将它们拉过每个芯片的网孔区域，从而模拟DNA合成器的流动几何形状。拟议的商业应用：如果证明可行，硅微制造和大规模生产的经济性将使通过这种方法制造的定制DNA微阵列能够非常有效地与当前技术竞争。由于只需要一个商用液体处理机器人和拟议的芯片就可以使该系统自动化，因此成本的降低可以极大地加快微阵列技术在生物学和遗传学研究中的使用。

The use of DNA arrays for numerous applications has expanded rapidly in recent years. These arrays are made primarily using photolabile ligands as blocking groups in an array format or by spotting DNA from organisms or a DNA synthesizer. We propose an on-chip, high-density DNA oligomer growth method that will use the standard phosphoramidite chemistry on a proprietary chip design. The key to the technology will be a chip that contains an array of <500um grids regions micromachined directly into a silicon wafer using Si microfabrication techniques. The grid regions are micromeshes fabricated by a wet chemical etching method giving grid mesh element sizes selectable from 10-100um. The growing oligonucleotides are attached to the SiO2 surface of the grid. This array of grids is placed over a second wafer that has <500um holes in registry with, and underneath, the micromesh areas. The ability of a DNA synthesizer to force equilibrium to completion by flowing reagents through the stationary support, and to thoroughly wash each sample, is duplicated on this chip by placing the nucleotide synthesis chemicals on the mesh and then drawing them through the mesh/hole regions of each chip, thereby simulating the flow through geometry of a DNA synthesizer. PROPOSED COMMERCIAL APPLICATION: If feasibility is demonstrated, the economics of silicon microfabrication and mass production will allow the fabrication of custom DNA microarrays by this method to compete very effectively with the current technology. Since only a commercial liquid handling robot and the proposed chips would be necessary to automate this system, the cost reduction could greatly accelerate the use of microarray technology in biology and genetic investigations.