Istituto di Fotonica e Nanotecnologie-CNR, Dipartimento di Fisica-Politecnico di Milano, Milan, Italy.
Lab Chip. 2012 Mar 21;12(6):1135-42. doi: 10.1039/c2lc21116e. Epub 2012 Feb 8.
We report on the integration of a size-based three-dimensional filter, with micrometre-sized pores, in a commercial microfluidic chip. The filter is fabricated inside an already sealed microfluidic channel using the unique capabilities of two-photon polymerization. This direct-write technique enables integration of the filter by post-processing in a chip that has been fabricated by standard technologies. The filter is located at the intersection of two channels in order to control the amount of flow passing through the filter. Tests with a suspension of 3 μm polystyrene spheres in a Rhodamine 6G solution show that 100% of the spheres are stopped, while the fluorescent molecules are transmitted through the filter. We demonstrate operation up to a period of 25 minutes without any evidence of clogging. Preliminary validation of the device for plasma separation from whole blood is shown. Moreover, the filter can be cleaned and reused by reversing the flow.
我们报告了一种基于尺寸的三维过滤器的集成，该过滤器具有微米级的孔，集成在商业微流控芯片中。该过滤器是使用双光子聚合的独特功能在已经密封的微流道内部制造的。这种直写技术可以通过后处理在由标准技术制造的芯片中集成过滤器。过滤器位于两个通道的交叉处，以便控制通过过滤器的流量。使用悬浮在 Rhodamine 6G 溶液中的 3 μm 聚苯乙烯球的测试表明，100%的球体被阻止，而荧光分子则通过过滤器传输。我们证明该设备可以在 25 分钟内不间断运行，而没有任何堵塞的迹象。已经展示了该设备用于从全血中分离血浆的初步验证。此外，通过反向流动可以清洗和重复使用该过滤器。
