Muck Alexander, Wang Joseph, Jacobs Michael, Chen Gang, Chatrathi Madhu Prakash, Jurka Vlastimil, Výborný Zdenek, Spillman Scott D, Sridharan Gautham, Schöning Michael J
Department of Chemistry and Biochemistry, New Mexico State University, Las Cruces, New Mexico 88003, USA.
Anal Chem. 2004 Apr 15;76(8):2290-7. doi: 10.1021/ac035030+.
A greatly simplified method for fabricating poly(methyl methacrylate) (PMMA) separation microchips is introduced. The new protocol relies on UV-initiated polymerization of the monomer solution in an open mold under ambient pressure. Silicon microstructures are transferred to the polymer substrate by molding a methyl methacrylate solution in a sandwich (silicon master/Teflon spacer/glass plate) mold. The chips are subsequently assembled by thermal sealing of the channel and cover plates. The new fabrication method obviates the need for specialized replication equipment and reduces the complexity of prototyping and manufacturing. Variables of the fabrication process were assessed and optimized. The new method compares favorably with common fabrication techniques, yielding high-quality devices with well-defined channel and injection-cross structures, and highly smoothed surfaces. Nearly 100 PMMA chips were replicated using a single silicon master, with high chip-to-chip reproducibility (relative standard deviations of 1.5 and 4.7% for the widths and depths of the replicated channels, respectively). The relatively high EOF value of the new chips (2.12 x 10(-4) cm(2) x V(-1) x s(-1)) indicates that the UV polymerization process increases the surface charge and hence enhances the fluidic transport. The attractive performance of the new CE microchips has been demonstrated in connection with end-column amperometric and contactless-conductivity detection schemes. While the new approach is demonstrated in connection with PMMA microchips, it could be applied to other materials that undergo light-initiated polymerization. The new approach brings significant simplification of the process of fabricating PMMA devices and should lead to a widespread low-cost production of high-quality separation microchips.
介绍了一种用于制造聚甲基丙烯酸甲酯（PMMA）分离微芯片的大大简化的方法。新方案依赖于在常压下于开放式模具中通过紫外线引发单体溶液聚合。通过在三明治结构（硅母版/聚四氟乙烯垫片/玻璃板）模具中模制甲基丙烯酸甲酯溶液，将硅微结构转移到聚合物基板上。随后通过热封通道板和盖板来组装芯片。这种新的制造方法无需专门的复制设备，降低了原型制作和制造的复杂性。对制造过程中的变量进行了评估和优化。新方法与常见制造技术相比具有优势，可生产出具有明确通道和进样交叉结构以及高度光滑表面的高质量器件。使用单个硅母版复制了近100个PMMA芯片，芯片间具有很高的重现性（复制通道宽度和深度的相对标准偏差分别为1.5%和4.7%）。新芯片相对较高的电渗流值（2.12×10⁻⁴ cm²×V⁻¹×s⁻¹）表明紫外线聚合过程增加了表面电荷，从而增强了流体传输。新型毛细管电泳微芯片的诱人性能已在柱端安培检测和非接触电导检测方案中得到证明。虽然新方法是针对PMMA微芯片进行演示的，但它可应用于其他可进行光引发聚合的材料。新方法极大地简化了PMMA器件的制造过程，应能实现高质量分离微芯片的广泛低成本生产。
