Roberts M A, Rossier J S, Bercier P, Girault H
Laboratoire d'Electrochimie (ICP), Département de Chimie, Ecole Polytechnique Fédérale de Lausanne, 1015-Ecublens, Switzerland.
Anal Chem. 1997 Jun 1;69(11):2035-42. doi: 10.1021/ac961038q.
This report describes a UV laser photoablation method for the production of miniaturized liquid-handling systems on polymer substrate chips. The fabrication of fluid channel and reservoir networks is accomplished by firing 200 mJ pulses from an UV excimer laser at substrates moving in predefined computer-controlled patterns. This method was used for producing channels in polystyrene, polycarbonate, cellulose acetate, and poly(ethylene terephthalate). Efficient sealing of the resulting photoablated polymer channels was accomplished using a low-cost film lamination technique. After fabrication, the ablated structures were observed to be well defined, i.e., possessing high aspect ratios, as seen by light, scanning electron, and atomic force microscopy. Relative to the original polymer samples, photoablated surfaces showed an increase in their hydrophilicity and rugosity as a group, yet differences were noted between the polymers studied. These surface characteristics demonstrate the capability of generating electroosmotic flow in the cathodic direction, which is characterized here as a function of applied electric field, pH, and ionic strength of common electrophoretic buffer systems. These results show a correlation between the ablative changes in surface conditions and the resulting electroosmotic flow. The effect of protein coatings on ablated surfaces is also demonstrated to significantly dampen the electroosmotic flow for all polymers. All of these results are discussed in terms of developing liquid-handling capability, which is an essential part of many μ-TAS and chemical diagnostic systems.
本报告描述了一种用于在聚合物基片芯片上制造小型化液体处理系统的紫外激光光烧蚀方法。流体通道和储液器网络的制造是通过以预定的计算机控制模式移动的基片上发射来自紫外准分子激光器的200 mJ脉冲来完成的。该方法用于在聚苯乙烯、聚碳酸酯、醋酸纤维素和聚对苯二甲酸乙二酯中制造通道。使用低成本的薄膜层压技术实现了对所得光烧蚀聚合物通道的有效密封。制造后，通过光、扫描电子和原子力显微镜观察到烧蚀结构清晰，即具有高纵横比。相对于原始聚合物样品，光烧蚀表面总体上显示出亲水性和粗糙度增加，但在所研究的聚合物之间存在差异。这些表面特性表明能够在阴极方向产生电渗流，在此将其表征为常见电泳缓冲系统的施加电场、pH值和离子强度的函数。这些结果表明表面条件的烧蚀变化与所得电渗流之间存在相关性。还证明了蛋白质涂层对烧蚀表面的影响会显著抑制所有聚合物的电渗流。所有这些结果都围绕开发液体处理能力进行了讨论，这是许多微全分析系统和化学诊断系统的重要组成部分。
